Fork issues, motor recommendations, and other newbie questions/issues

Hi all! I’m brand new to posting on ES, but have been scouring through the forums for months at this point. My mission is to find the BEST solution for my needs, but I don’t think I’ve came across it yet.

TLR
1. I converted a bike that I’m not certain can handle what I’m throwing at it and it’s making me concerned for my safety.
2. I need a motor recommendation to use with my 52v 13.5 ah Luna wolf pack v2 for commuting, hauling groceries and very short climbs. (30 miles+ at a reasonable speed, 13-18mph would be ideal)
3. I would appreciate opinions on the structural integrity of my donar bike and any recommendations for a new donar bike/upgrades I could make to my existing donar (replacing my fork with something sturdier for example)
4. Recommendations for a reliable motor to use with my new pack, be it mid drive, a front or rear hub drive or even front and rear hub drives.
5. What’s better for me geared, direct drive or a mid drive system?
6. HELP ME GET MORE STOPPING POWER

My uses for the bike:

I’ll generally be using the bike for casual weekend rides for shopping or just riding, to haul some groceries on the rear rack with panniers and commute to work sometimes. A comfortable cruising speed for any of the ranges that I mentioned would be approximately 13-18mph. Again, I don’t NEED to go fast, but I do feel like I’d appreciate having some more power that I can tap into at any point.

The weekend rides could potentially include a trip over the Williamsburg Bridge in NYC. I wouldn’t ever be hauling anything over it though. I would like to easily be able to get across that bridge from my home in Brooklyn, ride around manhattan for a bit in stop and go traffic and be able to get back home without charging (two trips over the bridge)

Some info on the Williamsburg bridge:

The path is about long a mile long and about half of that would be the climb...from what I have gathered across the web the gradient would be anywhere from 3-4%, and I’ve seen a mapmyride chart that peaked at 5.6%.

I think 30 miles would suffice, but the more the merrier....

The grocery or other hauling trips (with 2 panniers full of food) would be a round trip total of about 5 miles all flat paved roads.

My commute would also include the Williamsburg bridge 2x, with the rest being mostly flat paved roads.
Round trip total: 16 miles (if I just went to and from work nothing in between before or after) +4 miles for real world use I guess...so 20 miles.

Some background info on me and my current build:

I’m Matt, 5’10”, 210 pounds and I live in Brooklyn, NY...which is where I’ll be doing the majority of riding (on flat paved roads).

I originally set out to make a budget ebike and purchase a 1200w front hub kit from eBay for $350 and an open box battery for $250 on eBay as well.

I was excited, I converted my beater to a beast for $600...or so I thought....

I have been using a 1200w ebikeling front direct drive hub motor kit with a 52v 13.5ah Luna Wolfpack v2 on a single speed wyatt street king (4130 chromoly) with 700c wheels and rim brakes. I have yet to do any range testing because I have been very busy at work.

Before getting my Luna pack, I bought a “New(other)” hailong battery pack, it was 48v 14.5ah Sanyo cells that was marked as open box, the battery worked well for a a couple miles and then would sag down to its low voltage cut off.
Did some research and the results were inconclusive,realistically it could be a number of issues. I have never worked on batteries and don’t feel completely comfortable, so I searched for local repair options to no avail.
After doing some research I concluded Luna cycle would be my best bet for a battery being that they are in the USA and have an excellent reputation among DIY’ers.
So, I I set up a call with Luna to get some background info on their batteries and to be honest, the dude had a great pitch for the battery and as a salesman myself I appreciated it and pulled the trigger on it.

I have no issues with the battery thus far.

The kit has worked great thus far, but I feel as though it is too powerful for my needs I would much prefer range to power for my uses.

I am much more concerned about the integrity of the kit itself, the stopping power and quality of the donar bike. I’ll get into my specific concerns later.

I can EASILY push past 20 mph and I feel as though that’s plenty (20mph). Speed isn’t the motivation here, it’s more traveling by bike, but without using any effort....so speed isn’t a huge concern for me, but at the SAME time buying a more powerful motor and having some more power to tap into is also a plus.

So my build is fully functioning at this point, but I do have some concerns.

My concerns:

Before converting I had the bike safety checked by my lbs, opted to not change the brake cables, although recommended, but I did swap the tires to marathon plus tires.

I’m concerned about the integrity of the frame itself. The bike was rather cheap in 2014 when I purchased it, about $400, it has some rust. I don’t think anyone has ever converted a Wyatt street king, I’m genuinely worried that the bike itself can even handle the sort of stress I’d be putting onto it, especially at the front fork.

It’s been my beater for 6 years at this point and yes my lbs said it was fine, but I didn’t strap a kit onto it at that point, and who’s to say it won’t fall apart at 20mph?

So the bike has rim brakes, which worries me. I ended up swapping the pads out to ebike specific koolstop pads and it has definitely been an improvement from my old ones, but I feel as though I’d be much more comfortable and have much more stopping power with some disc brakes or even swapping these cheap calipers with something better like 105s or ultegra if that would be enough.

I know there are varying opinions on this, and I also admit that I haven’t even tried a heavy ebike with disc brakes, but my perceived suboptimal stopping power with these rim brakes brings me to four options:
1. Buy a new bike with disc brakes and use a front hub (budget for the new bike would be +/-$1000)
2. Replace the existing fork with a disc brake ready steel fork and get some discs for just the front and use a front hub(would appreciate any recommendations for a good fork)
3. Buy a new bike with discs and get a mid-drive or rear hub motor.
4. Upgrade the calipers and keep the same fork.

Onto the kit, the wheel just doesn’t seem straight, there are some spokes that aren’t completely straight and it just seems like it’s been poorly assembled. Ultimately, I don’t want to run into ANY issues at 20mph in regards to the integrity of a wheel. Ebikeling has approved my return and I’ll almost certainly be returning this, as I don’t want to take ANY chances.

The kit came with a cheap torque arm that wasn’t very confidence inspiring, so I added a grin torque arm v2 to the other side which definitely helped me feel a bit comfier.

Ebikeling even messaged me saying that 1200w is too powerful for my front fork. Would I be better off with a rear kit? I have also heard good things about mid drive as well...I’m really open to any and all recommendations.

My budget for the “kit”...be it a complete kit or total for the parts (motor, controller, throttle, PAS, display, etc.) would be: $1000

Although Ebikeling has a decent reputation and reviews, but at the end of the day here, I don’t feel comfortable using their product. I would feel much more comfortable with a kit that someone has already used and tested extensively and the same would go for a donar bike and/or new fork.

I have attached a photo of the build below:

https://imgur.com/3xhzNqV

What I think I should do at this point:

I’m pretty much convinced I’ll be returning the ebikeling kit and replacing it with a recommended kit from you guys. I am considering buying a entire new donar bike or new fork to convert as well.

So I built the ebike, I like the idea of it, I’m worried about the integrity of the parts used.

I know that I’ll want whatever is “best” eventually and I’m almost certainly sure that there are better options than the ebikeling kit.

To be fair ebikeling has been excellent with their support, but I would much rather buy from a more established reputable dealer, like grin or em3ev or even Luna if they get anything back in stock..or maybe somewhere else if you guys recommend it!

At this point in my life, I’m the type of person that buys things with the intention of using and keeping it for a very long time, BIFL sort of purchase (buy it for life) and I do not feel as though the street king or ebikeling kit is it.

Ultimately for me to feel confident and comfortable I feel as though I need a safe and reliable motor and frame that has withheld the test of time.


What I need from my friends at endless sphere:
1. Help me figure out how to get more braking power
2. Help me find the right motor for my needs and one that I don’t have to worry about breaking down too often and has been built properly, with safety and longevity in mind.
3. Opinions on my frame/build in regards to its structural integrity. (Any other comments or criticism not related to its integrity would also be appreciated!)

I know this was long, but I wanted to be as detailed as possible...I’m sure your responses will help me get on the road feeling comfortable and confident and I thank you taking the time to help!

Ditch the front 1200W hub motor, get a rear hub motor, Leafbike 1500W (direct drive) kit (display) and a controller to match your batteries with 40-50A discharge for the controller. MAC geared motor would suffice too at www.em3ev.com or a BBSHD mid drive from Luna Cycle would work just as well too. I would skip the mid drive, go MAC or Leaf, 48 or 52V whatever your battery voltage is, match to controller, 35-45 or 50A controller discharge.

Thanks for the reply, do I have to worry as much about torque on the rear axel as much as the front?
Keep in mind I’ll be hauling some groceries on the back as well.

If I’m understanding correctly you’d recommend a geared hub motor over a mid drive or direct drive motor for my use.

The issue of my stopping power still remains even after swapping out my kit. This bike will not accept discs, like I said in the post I’m considering throwing on a new fork and adding some discs to the front. I wonder if this would be enough.

The first thing I recommend is retitling your thread, because that kind of title actually makes people *avoid* threads. A good clear subject will attract the right people to help you with the stuff you need.

Everythign else is inline below:

Kemosabe70 said:

My mission is to find the BEST solution for my needs, but I don’t think I’ve came across it yet.

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Most likely you'll have to invent it. My experience is that no one makes a solution that perfectly fits anyone's problems; there are always compromises. So you wind up taking bits of all sorts of systems to make what you need. PITA, and takes a lot of integration work, trial and error, etc. But we'll see what we can do.

1. I converted a bike that I’m not certain can handle what I’m throwing at it and it’s making me concerned for my safety.

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Easy to fix--pick a better bike that has the features you need for your specific usage. Or, build one (nothing suits my needs, so that was my only choice).

2. I need a motor recommendation to use with my 52v 13.5 ah Luna wolf pack v2 for commuting, hauling groceries and very short climbs. (30 miles+ at a reasonable speed, 13-18mph would be ideal)

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Unless the climbs are extreme, pretty much any common motor can handle that--500-1000w type DD or geared hubmotor, or similar middrive.

3. I would appreciate opinions on the structural integrity of my donar bike and any recommendations for a new donar bike/upgrades I could make to my existing donar (replacing my fork with something sturdier for example)

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Donor bikes should be picked based on your specific needs. If you have a lot of groceries or other stuff to carry, very often, a cargo bike is probably a better option than converting a regular bike to carry stuff. (I've done it all, for that stuff, so....)

6. HELP ME GET MORE STOPPING POWER

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Depends on your weight and specific conditions and tires, etc. If you're not heavy, not going fast, and on decent roads, with typical tires, dry conditions, then any decent rim or disc brake will work fine, as long as you have good pads and adjust them correctly.

If you're in muddy conditions, disc are probalby easier to keep working.

Your tires have to be able to grip the surface to stop you, so if you're on smooth pavement, good slick sticky-compound tires are best. If you're on unpaved surfaces, knobby stuff works better. Etc.

Koolstop makes good pads for lots of popular brake systems, and they work very well, as long as you maintain the brakes. (nothing works well if contaminated).

I used KS pads on rim brakes to stop CrazyBike2 and SB Cruiser (front brake only!). But the fork legs on the cheap suspension forks twist under braking and lessen the braking, so had to add a brake booster arch to the bosses to keep them from twisting as much...but still ended up having to put brakes on the front *and* the back of the fork for the 500lb+ SBC trike, because the forks were crappy and not stiff enough to keep the pad surfaces parallel to the rim.

After breaking the fork in the only crash I've been in, and some convolutions, I ended up building a nonsuspension fork and using an Avid BB7 Mtn disc brake on there, 200mm rotor, with the semimetallic pads, and the Avid adjustable lever. Skids the wheel easy, so tha'ts the max braking possible on taht wheel. Still using a CST City slick-center tire with soft compound for good grip. Will be adding rear BB7s once I can rebuild the frame back there to handle them.

The path is about long a mile long and about half of that would be the climb...from what I have gathered across the web the gradient would be anywhere from 3-4%, and I’ve seen a mapmyride chart that peaked at 5.6%.

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Most likely just about anything in 500-1000w could do that, just like your speed requirements. If you're curious you can go to http://ebikes.ca/simulator , read the whole page so you know what everything is and how to use it, then pick a system and setup that's similar to what you already have under those conditions, and see if it can do that. If not, up the controller power and see if the motor overheats. If not, then a bigger controller would probably fix it. If it overheats, you need a bigger motor, too. Etc., until you get the result you want.

I think 30 miles would suffice, but the more the merrier....

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Well, that's up to your battery, speed, riding style, terrain, and wind. The motor/etc doesnt' figure much into it.

But I would say you would probably use 15-20wh/mile for most of your described riding, and perhaps 25-30wh/mile for fast riding / uphill riding.

So let's say you have 20wh/mile average (probalby higher than reality). To get 30 miles, you need at least 30 x 20 = 600wh battery. Youv'e got that already in the Luna pack, so except for allowing for detours, headwinds, pack aging, etc., your'e set there.

If you do hard acceleration with frequent stops and starts, you'll use more power, and have less range. Same thing if you go faster.

Before getting my Luna pack, I bought a “New(other)” hailong battery pack, it was 48v 14.5ah Sanyo cells that was marked as open box, the battery worked well for a a couple miles and then would sag down to its low voltage cut off.

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Probably it's a balance problem. If leaving the pack ont eh charger constantly whenever you can monitor it, for as long as possible, changes the problem, making it work better for longer, then that's the problem. The actual cause of the problem could be several things, but none of htem are permanently fixed by the long charging (though you can just always leave it on the charger whenever you aren't using it, and it would help).

The kit has worked great thus far, but I feel as though it is too powerful for my needs I would much prefer range to power for my uses.

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That's easy to fix, by using less throttle.

If you can't make yourself do that, and the kit itself has no settings in it's display (if any) to limit usage with different levels, then you can add resistors to the throttle (bunch of threads about that) to limit the max speed and acceleration.

If you need more control over power usage, speed, etc., the Cycle Analyst can be installed between the throttle/etc and the controller, to modulate your throttle input to the controller to obey your limits.

Before converting I had the bike safety checked by my lbs, opted to not change the brake cables, although recommended, but I did swap the tires to marathon plus tires.

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Brake cables will help with stopping power and responsiveness. IF they're sticky, the pads don't retract right and can keep touching the rim, wearing them and potentially glazing the surfaces, reducing stopping power. If they're stretchy, you don't get as good a control over the braking as you could, or even have problems with enoguh braking force at all. If the cable has any broken strands, each one will halve the force you can apply thru it.

I’m concerned about the integrity of the frame itself. The bike was rather cheap in 2014 when I purchased it, about $400, it has some rust. I don’t think anyone has ever converted a Wyatt street king, I’m genuinely worried that the bike itself can even handle the sort of stress I’d be putting onto it, especially at the front fork.

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Does it wiggle, flex, or otherwise show signs of a problem?

What specifically and exactly concerns you about the frame's behavior while riding?

And the same for the fork?

So the bike has rim brakes, which worries me. I ended up swapping the pads out to ebike specific koolstop pads and it has definitely been an improvement from my old ones, but I feel as though I’d be much more comfortable and have much more stopping power with some disc brakes or even swapping these cheap calipers with something better like 105s or ultegra if that would be enough.

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Can the brakes make the wheel skid? That's the best any brake can do.

Do they modulate well? Meaning, do you get feather braking at light lever touch, graduating up to lockup at full lever pull? Then that's the best you can get with any brake.

Onto the kit, the wheel just doesn’t seem straight, there are some spokes that aren’t completely straight and it just seems like it’s been poorly assembled. Ultimately, I don’t want to run into ANY issues at 20mph in regards to the integrity of a wheel. Ebikeling has approved my return and I’ll almost certainly be returning this, as I don’t want to take ANY chances.

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Most of the kits are likely to have spoke issues, if not now, later. The spokes in them are too thick for the rims used, and just machine built, not retensioned, etc. What I would do is either just get a motor, and build your own wheel (or have your LBS do it), or simply take the one you've already got and do the same--take the rim and spokes off, and replace them with a good rim and 14g spokes (13/14 butted if the spoke flange holes are too large in the motor).


Most of the actual motors are all the same as each other. Even the motors Grin and Luna have are, with a few exceptions at Grin like the All Axle hub, exactly the same stuff everyone else has. The rims and spokes may be different (better rim, thinner spokes appropriate for the rim), and the wiring external to the motor may be thicker or better connectorized, etc., but there's really not any significant difference (if any at all) beyond that.


*Controllers* vary greatly, and there are some very good ones out there, but most of them are the same generic stuff jsut rebranded, sometimes rewired or reconnectorized. However...even the generic cheap "junk" can work perfectly fine. I'm still using a $20-ish generic whatever off ebay on the SB Cruiser for one of the motors, with the only thing I had to replace on it were the main big can capacitors, right at the beginning--but I also had to do that on a really expensive Lyen controller years before, so no difference there.

However...there is a great variety of *features* in controllers, even in the generic stuff, so you may wish to base your controller choice on all the things you would like it to be able to do for you. (levels of assist to save power or hillclimbing, lowspeed vs fast, etc., power usage monitoring, pedal cadence/torque-based assist, current(torque) motor control (FOC), etc.


Then there is easy of connectivity. The best way to get everything you want is to piece it together from the best you find everywhere. But youll have to put your own connectors on , cuz they probalby wont' match.


If you're already thinking of luna or grin or em3ev, grin has Ready To Roll kits with water resistant connections, etc. Dunno if the other two have equivalents, but I'd guess they probably do.

Ebikeling even messaged me saying that 1200w is too powerful for my front fork.

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Despite the words people use talking about this stuff, no "wattage" is too powerful for a specific fork, but too much torque can be. I've used 2kw with a 9C hubmotor and various cheap forks on the heavy CrazyBike2, and similarly with a Crystalyte hub on the front of SB Cruiser when it was first built. With good torque arms, no problems. Only without proper torque arms have I had issues--except:

With any hubmotor on the front fork, torque from the motor can cause the stanchions / lowers to stick, so you don't get good suspension action while acclerating or hill climbing. Doesn't affect it other than those conditions, unless the motor axle shoulders are wider than the regular wheel ones, and can push the lowers outward at an angle and cause poor suspension performance.

Nonsuspension fork wouldn't have this issue. The better the fork, the less of an issue this is (like DH forks...but the better forks dont' usually have dropouts, they use thru-axles, which won't work with any hubmotor I know of except the Grin All Axle one).

Hard stops with disc brakes will put more load on the fork than the motor will.

So...you *can* break a fork with a motor...but it's not likely to happen with good torque arms properly mounted, unless the fork already has a problem.

I have attached a photo of the build below:

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Can't see the external image. If you attach it directly to the post with teh attachments tab, and upload it directly to the forum, then anyone that can read your post can see the pic.

Kemosabe70 said:

The issue of my stopping power still remains even after swapping out my kit. This bike will not accept discs, like I said in the post I’m considering throwing on a new fork and adding some discs to the front. I wonder if this would be enough.

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Chalo, a bike mechanic who used to be here, often suggested adding a brake booster.

Examples:
https://endless-sphere.com/forums/viewtopic.php?f=3&t=81765&p=1202364#p1202364 (has picture)
https://endless-sphere.com/forums/viewtopic.php?f=3&t=95046&p=1394563#p1394563
https://endless-sphere.com/forums/viewtopic.php?t=52763#p784131

Search link:
https://endless-sphere.com/forums/s...1&sf=all&sr=posts&sd=d&st=0&t=0&submit=Search

Mark5

Wow very cool, thanks!

Thank you for your detailed response Amber!

I will be headed over to my LBS tmr to change the brake cables and get the Kool Stop pads properly aligned.

I am going to use this advice and further my research and I do have some questions, but these would be more relevant after I get some in testing tomorrow.

Will report back tomorrow.

Thanks again!


p.s. I attached an image of the build!

Change the title, please!

I’d say described use can be done with whatever kit, no worries. If your frame doesn’t hold up, normally you’ll start noticing cracks and flexing, won’t be sudden catastrophic failure if it’s steel.

I’d think about weight distribution of the bike, if the front hub works for you then it would balance rear panniers better than a rear hub combination.

The way I see it, your bike only needs two things. Its a good bike, but if you overload it, like 50 pounds on the back, your speed will need to slow. Just allow some time to get home from the grocery. Your fork is fine, your front motor is fine.

1, Learn to tune your spokes on the motor wheel. You don't need to be a wheel builder. Just learn how to check your spoke tensions, and then snug up anything actually loose.

Look at your spokes, they are laced in a 4 spoke pattern. Each 4 has two spokes on one side that cross. Between the cross and the rim, squeeze each pair to locate any that are noticeably loose. Don't ride with any terribly loose spokes and you will get thousands of miles from that wheel. Motor wheels typically stretch out in the first 500 miles, so you do need to check spokes especially often on a new wheel.

You might learn to straighten wheels later, but for now, just don't ride with loose or any broken spokes.

2 Brakes. Disc on the front will help a lot. It may not stop better, but it will stop good without needing as much fussy adjustments as rim takes.

Easy way here is swap the fork for one with disc mounts. But you can weld a disk mount to the existing fork pretty easy. My cruiser build in my signature includes some details how I did it for the Schwinn.

Going forward, build what you need can be the real answer. That's how I got led to buying a welder, and modifying the Schwinn cruiser. But there are great longtail cargo bikes out there, if you have some cash to invest. Any longtail is better designed for carrying the groceries home than a typical bike with panniers added.

Braking, I really like the phaserunner with a rear DD hub for regen. everything is easily programmable and it also has electronic freewheeling so your bike will coast like a normal bicycle. its tiny, it will almost fit inside a toilet paper roll. its also waterproof. you can download the app to your phone and make changes to phaserunner settings while out on the road, not on the fly, you need to plug them together. you can also program the amps to match your cells/battery to maximise cycle life
I like the mxus xf40 for a DD, good power and not too heavy.
a bike with rear panniers, it would have to be hardtail and id probably use a Maxxis Hookworm 26x2.50 to absorb some of the road

Hi all, thanks for all the input!


I think I need some more guidance before replacing any brake cables or calipers.


I did some runs on a smoothly paved Brooklyn road I was able to stop the bike traveling at 20mph after hard braking in about 25ft with the rear tire skidding.


DISCLAIMER: I’m not sure how accurate my speedometer is on the s830 display that came with the ebikeling kit. I was using my iPhone’a built in measuring app to measure the sidewalk squares next to where I was testing


I wasn’t able to get the front to skid, but I’m also not sure if It’s supposed to skid?


In terms of brake modulation, I was able to feather the brake gradually to a halt. I guess the Kool Stop pads are working well. The brakes do feel pretty spongy though, not sure if swapping to new cables would fix that. My cables are also the original cables the bike came with and I’ve ridden it at least 500 miles, I have attached an image of the front brake cables that’s end cap thing has fell off.


While straddling the bike, I pushed down on the handles bars and the fork does flex away from the frame. In testing, the bike does feel pretty wobbly, almost as if the fork is flexing outward. It’s hard to tell being that I’m riding on busy NYC street, so I can only go by feel. It doesn’t feel very rigid, I at least feel some sort of flex at least at the front.


At full throttle on pedal assist 3-5 from 0 with no pedaling I hear a noticeable gurgling noise from the motor, the bike also shakes and I hear some rattling from the handlebars and from the controller mounted to the back of the frame. This noise dissipates after gaining some speed.


I also felt some sort of jolt in the fork (I think) when accelerating from 0 at those higher power levels. I took a closer at the front fork eyelets and noticed gap between the eyelet and the motor axel on either side of the axel. I have attached an image of this, I wonder if that could be an issue? [/https://imgur.com/a/QulBr7O] On...ld look into getting a spoke tightening tool.

I have koolstop rim brakes with 80v 5,000 wAtt system think before you go No zombie keep your chin up look as far as you can down the road your brain already knows what's under your feet you don't have to look at the road underneath your front tire pick your chin up pick your eyes up and look on a 250 Ford. As your brain is very capable of remembering what it's already seen Ride

Attached some better photos of the left side eyelet with ebikeling torque arm.

[/https://imgur.com/a/9ESTpJe]

Kemosabe70 said:

I did some runs on a smoothly paved Brooklyn road I was able to stop the bike traveling at 20mph after hard braking in about 25ft with the rear tire skidding.

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The rear will always skid before the front does, given same conditions, tires, and braking, because weight transfer to the front. If the tires are different, skid point can be different, too.

I wasn’t able to get the front to skid, but I’m also not sure if It’s supposed to skid?

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As I said before, maximum braking is skidding the front wheel. If you can't skid the front wheel, your brakes are not doing the best job they could. YOu don't want them to automatically skid, but you should be able to *make* them skid if you pull the lever hard enough. It's actually a legal requirement of a bicycle in many places.

Possible problems include: (There are different fixes for each problem. )
the pads aren't able to press against the braking surface hard enough (might be insufficient preload on the cable; tighten the adjusters till the pads touch the rims then back off just a hair)

the pads are not parallel to the rim (check websites/videos for adjustment procedures)

the surface is not clean, (clean the rim (and the pads) with appropriate cleaners)

the cables are too stretchy (replace them with good new ones)

the handles are the wrong type to match the brakes, so the handle hits the grip before the brakes are fully pulled. (change the handles to the correct type for the brake type)

the fork leg twists under braking so the pad is pulled away from the braking surface at the front end (you can't usually see it visually, but it happens) and pressed harder at the back end, but not flat, so braking is reduced. (install a brake booster arch on the bosses)

If none of those fixes it, I'd have the LBS carefully check them to see what is going on.

In terms of brake modulation, I was able to feather the brake gradually to a halt. I guess the Kool Stop pads are working well. The brakes do feel pretty spongy though, not sure if swapping to new cables would fix that. My cables are also the original cables the bike came with and I’ve ridden it at least 500 miles, I have attached an image of the front brake cables that’s end cap thing has fell off.

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I don't see any images, just links to an external site I can't open. If you use the attachments tab, and upload the image directly to the forum, then anyone that can see the post can see the images.

Spongy is often cables for one reason or another, but can also simply be not being adjusted right. If one end or edge of the pad hits the braking surface first, instead of meeting it flat-on, it can feel like that.

If the cable housings are not the incompressible kind, it'll feel like that. (sometimes shifter housings are used on brakes, and that's a problem). Jagwire makes an incompressible housing (as do others); I have a roll of it here to eventually change out the housings on my trike when I get that far.

If one of the strands in the cable is broken, the cable will have twice as much stretch and feel less capable than with all of them. (half the strength for each strand broken).

While straddling the bike, I pushed down on the handles bars and the fork does flex away from the frame. In testing, the bike does feel pretty wobbly, almost as if the fork is flexing outward. It’s hard to tell being that I’m riding on busy NYC street, so I can only go by feel. It doesn’t feel very rigid, I at least feel some sort of flex at least at the front.

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If it's a cheaper suspension fork then it likely doesn't have good bushings/etc in the lowers-to-stanchion tubes, so they can wiggle back and forth. That's normal. Better forks have better bushings, reducing this.

Can also be from the headset being loose. This will cause the handlebars to feel like they move a bit back and forth when you brake, or if you hold the front brake and try to push the bike forward while sitting on it. If the bars don't move, the headset is probably tight. If they move, you can tighten the headset; there's instruction pages and videos on this out there or the LBS can do it for you.

At full throttle on pedal assist 3-5 from 0 with no pedaling I hear a noticeable gurgling noise from the motor, the bike also shakes and I hear some rattling from the handlebars and from the controller mounted to the back of the frame. This noise dissipates after gaining some speed.

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Could be normal for the particular controller and motor combination.

If it were a wrong phase/hall combo it'd use a lot of power and get pretty hot, usually, as well as making a fair bit of vibration and racket. Probably is not that.

FOC controllers will generally not create vibration and noise with a motor once they're setup correctly for that particular motor (but they are not just plug-and-play with a motor they're not already setup for, for that reason).

I also felt some sort of jolt in the fork (I think) when accelerating from 0 at those higher power levels. I took a closer at the front fork eyelets and noticed gap between the eyelet and the motor axel on either side of the axel. I have attached an image of this, I wonder if that could be an issue?

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Again, no image visible, but eyelets don't support anything but whatever is bolted onto them (racks, fenders, etc).

If you mean dropouts, then if there are gaps, the motor axle can move inside them, and torque arms are used to prevent that. TAs must be mounted correctly and tightly so that can't happen, or eventually the motor axle rocking back and forth will spread the dropouts enough to let the axle spin inside the dropout, if the TA is loose-fitting enough to allow this.

I can’t find any info on the web about the internal battery resistance of the Luna Wolf pack V2 13.5ah and it’s hindering my ability to properly use the grin motor simulator. Does anybody know how I could calculate it or know this info?

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Just use the default resistance--it's probably close enough. If you want to you coudl try once default, then once doulbeing it, then once halving it, and see if there's much difference in the results. Or even go an order of magnitude either way.

If you want to know what it is by math, you could check the Luna site to see what cells they use in it, and how many series and how many parallel, Then find the spec sheet for that cell, and it's internal resistance listing. Mulitply that by the number o series cells (like 13s, 14s), then divide it by the number of parallel cells (like 4p, 6p, etc). That gives the cell resistnace total (leaves out the BMS, connections, wiring, etc, but you can only know those by actual measurement).

I’ve concluded that I like fast acceleration, but there isn’t any circumstance I’d need to go above 20 mph. Does anyone have any recommendations for a motor that work work efficiently with my pack? The drag and weight of the big direct drive motor makes pedaling the thing really uncomfortable, I wonder if a geared motor or mid drive would be better in my case?

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Yes, they would, if you prefer to be able to pedal "normally" with no motor power.

If you mean that pedalling it while also using motor power is uncomfortable, then it's more to do with the added weigth in various places changing the handling of the bike from the way it was before adding htem.

For which motor...there's a lot of them that would do what you want. For a geared hub, the MAC is a generally good choice for higher power, up to about 1000w (higher for short bursts). Lower power there's a number of Bafangs that would work.

MIddrives...depends on the specific bike and exactly what you want out of it, because most of them are going to replace your cranks and be down "in the way" at the BB of the bike. Some frame designs preclude isntalling some drives, or require modification to frame or drive or mounting system. Most of them are going to change the way you pedal the bike, whether or not you're using the motor, often by spacing the pedals further away from the frame than they used to be, which causes some people problems. Most will remove the ability to shift the front gears, leaving only the rear gears available; they may change the chainline to the rear which may affect the ability to shift into all the rear gears. Etc. Most of that is not a problem if you only use the motor, but if you need to use the pedals without using the motor it *can* be a problem for some people.

After checking the spokes there are some pairs that have a bit more give than others, but they all have a bit of give. I guess I should look into getting a spoke tightening tool.

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Don't get the super cheap ones--they don't usually fit the nipples well, and you can strip the nipples out and then be unable to fix the problem without replacing the damaged nipples. The LBS will carry good ones (it doesn't have to be a Park Tool level unit) and should be able to tell you how to use it. If not, the http://sheldonbrown.com site has plenty of bike-maintenance info including wheelbuilding and fixing, in an easy-to-understand style.

hard to pedal a DD hub, yes it is. that's why I mentioned the virtual electronic freewheeling of the Phaserunner.
your battery isn't made for high amps, you don't have the 30Q wolf, its GA or LG or? so 7amp absolute max per cell, its 4p so 28amp max controller? that's another reason I mentioned phaserunner, you can program it 20 amps, 28 amps, 40amps, 60 amps.

adjustable regen, 90% of my braking is regen, I don't use my rear disc brake at all. front hydraulic disc brake is 208mm I think and it will skid my front 26x3.0 tire under hard stopping. personally I wouldn't put more than 20 amps through a motor on the front fork nor regen, is that an aluminum fork?

you want to take off fast with a big diameter wheel and only 28amps. my first motor was a bafang 48v 500watt T12 geared motor, top speed was about 20mph maybe a little better with a 26x2.50 hookworm and a 20 amp controller. if I went full throttle with a fully charged battery it would almost pick the front wheel up, 1000 watts.

youre probably better off with a geared hub in the back tire or a mid drive, I don't think your battery can give you what you want in a DD.

theres a member here from Australia who built a bike just like what you want, made it "stealth" with rear panniers so it was hard to tell it was an ebike. ill go find the thread and post the link here

a tip for those using search here on ES, if you can remember a particular/odd word in the thread it helps.
I searched: lycra, to find the link :wink:

https://endless-sphere.com/forums/viewtopic.php?f=3&t=104679

Yes I did mean drop outs, my mistake.

Uploaded the pics! The fork itself seems bent outward on one side. Check it out.

is that like a 1/8 inch gap between the flat of the axle and the drop-out????? like the drop-out beens flared, its supposed to be tight, no gap.

it actually looks like the fork should have had 3 washers worth of thickness in between the motor and the drop out so the drop out went onto the flats of the axle, meaning like a 3/8 thick washer. maybe its my eyes playing tricks but....

its like the motor axle is too wide for your fork.

Some more photos attached.

goatman said:

is that like a 1/8 inch gap between the flat of the axle and the drop-out????? like the drop-out beens flared, its supposed to be tight, no gap.

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Yeah it is, it’s on the side that I previously hadn’t had the torque arm on. Recently installed it this past week and have been riding without it for About 30 miles before that.

id be unbolting the nuts and having a good look how the axle is sitting and see if the dropout got flared. also grab a magnet to see if the fork is aluminum.

goatman said:

hard to pedal a DD hub, yes it is. that's why I mentioned the virtual electronic freewheeling of the Phaserunner.
your battery isn't made for high amps, you don't have the 30Q wolf, its GA or LG or? so 7amp absolute max per cell, its 4p so 28amp max controller? that's another reason I mentioned phaserunner, you can program it 20 amps, 28 amps, 40amps, 60 amps.

adjustable regen, 90% of my braking is regen, I don't use my rear disc brake at all. front hydraulic disc brake is 208mm I think and it will skid my front 26x3.0 tire under hard stopping. personally I wouldn't put more than 20 amps through a motor on the front fork nor regen, is that an aluminum fork?

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I have the the 13.5 ah pack with Lg mj1 cells. It’s a steel fork.
I watched a video on the phase runner and free wheeling from grin and I’ll admit it wasn’t the easiest to follow, but I’ll head over to ebikes.ca and read more about it tomorrow. It does seem really cool and I love having video guides to watch through.

goatman said:

you want to take off fast with a big diameter wheel and only 28amps. my first motor was a bafang 48v 500watt T12 geared motor, top speed was about 20mph maybe a little better with a 26x2.50 hookworm and a 20 amp controller. if I went full throttle with a fully charged battery it would almost pick the front wheel up, 1000 watts.

youre probably better off with a geared hub in the back tire or a mid drive, I don't think your battery can give you what you want in a DD.

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Would a smaller wheel get me better acceleration?
Although I wouldn’t travel over 20 mph often I’d like to have the ability to push passed 20 would I be better off with a 750w motor?
I’m actually considering selling this fixie and getting a new donor. I road my brother’s SE big flyer and I really liked the ride with the plus tires that we ran at 25 psi. It was so soft and cushy. I wouldn’t want something like a big flyer, but maybe something with plus or fat tires would be nice. I’m not sure about the efficiency differences there, but i did see a nice trek dual sport that I liked with a front suspension, but it’s made of aluminum so I don’t know if it would work. Surly also has some nice steel bikes similar to what I have now and some fat bikes. I feel like I could appreciate a suspension being that I love curb hopping 8)

So what do you think I should shoot for In a set up if I want a good balance between taking off fast, 25 mph top speed, and good range, on either a hybrid like a surly, a hybrid with suspension like a trek dual sport

I wonder if 2 small geared hubs at the front and back would work well here?

A beefy rear hub does sound fun, but what’s best in terms of accelerating, rear or mid drive?

goatman said:

theres a member here from Australia who built a bike just like what you want, made it "stealth" with rear panniers so it was hard to tell it was an ebike. ill go find the thread and post the link here

a tip for those using search here on ES, if you can remember a particular/odd word in the thread it helps.
I searched: lycra, to find the link :wink:

https://endless-sphere.com/forums/viewtopic.php?f=3&t=104679

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Thanks for sharing I’ll check this out!

goatman said:

id be unbolting the nuts and having a good look how the axle is sitting and see if the dropout got flared. also grab a magnet to see if the fork is aluminum.

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According to [/https://wyattbikes.com/shop/archi...e if it has? Maybe I could just swap the fork

atleast its not aluminum, other members here can help you figure it out

Kemosabe70 said:

Yes I did mean drop outs, my mistake.

Uploaded the pics! The fork itself seems bent outward on one side. Check it out.

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I think I see what you're talking about.

First, are both the motor axles fully seated in the dropout? If either one is slightly not, then it will make the fork look funny because the wheel is tilted. This would also explain braking problems, becuase the rim surfaces can't be flat to the pads if the wheel is at an angle.

Does it look normal without the motor in it (with the regular wheel instead)? Did the motor have to be pushed into the dropouts. spreading the fork? If so, the motor is too wide for the dropouts, and the fork happens to be sligthly easier to bend on the fork leg that is sticking out more.

If it's the same either way, then it's just the fork itself, either designed that way or a flaw in manufacturing.


Now, on the gap between axle flats and dropout sides: That shouldn't be possible, unless the dropouts are spread out. Was this gap present originally? If not, it means the axle is rocking in the dropouts and is not mounted correctly, that the torque arms are not mounted right or not tight enough (meaning, the hole in the arm is too large so teh axle can move in it, instead of being a tight fit).

If the gap was there originally, then either the motor axle is way skinnier than I've ever seen (10mm between flats is normal), or the dropouts were already bent/ spread, or were cut or ground out for some reason. (regular wheel axles are 9 or 10mm).



Since your fork ins't suspension, then it cant be bushings causing the flex, so it's still possibly a loose headset. The fork may have some forward/backward flex in it, that's normal and desirable for nonsuspension forks like that (helps with some bumps, etc).