Veloman's ebike builds

veloman

10 MW
Joined
Sep 13, 2009
Messages
3,090
Location
Austin TX
Here are links to some of my earlier builds. I lost the link to my first build in '09, but that thing just handled so awful and had sla.

5th ebike build - GT Ricochet 450w - http://endless-sphere.com/forums/viewtopic.php?f=6&t=20801
3, 4th ebike build - TT Road racing Cdale 750w - http://endless-sphere.com/forums/viewtopic.php?f=6&t=19409
2nd ebike build - Giant rigid mtn bike 450w - http://endless-sphere.com/forums/viewtopic.php?f=6&t=17129

The first 3 pages of this thread are using a Mac hub on full suspension bikes. What a world of a difference in terms of performance, handling, and reliability. I was stuck on non-hub motors at first, but they really work well aside from making bumps worse.

June 2012 update - I just discovered that the 36v 11ah lifepo4 I got from Hyena last year is capable of >43amps peak. Voltage sagged 4v. I always thought it was limited to 21amps, but that must have been my controller settings. I built up the black khs with the 6 turn and this battery for my gf to ride last night. She says it's scary and only once pulled the throttle all the way up a hill I was encouraging her to open it up on. She accelerated from 15mph to 25mph+ while on the 8% grade...... :twisted:

This must be my 10th bike I've had electrics on now... I am finally riding real full suspension and it sure makes a difference. Only have done a mile so will report back later. It's using all the same parts as my previous two bikes this Fall - 6 turn Mac limited to 21amps on lifepo4 36v 11ah, or 48v 5ah lipo. It's not all that exciting but gets the job done. I will constantly be tweaking it, such as:

DONE- Get the battery in the main triangle!!!! (I hate the look and feel of it on a rear seatpost rack). It will fit JUST fit, clear of the crank arms, laid on it's side. Not ideal, but the best I can do with this frame. I still have my eye out for the perfect ebike frame....

DONE (rear)- Design a homemade mechanical lockout for rear and front shocks. The plan is to pull a lever on the bars which will hold the suspension stiff so I can stand and pedal hard without loss for nice acceleration or hill climbing on smooth road.

DONE - Add a pre-charge resistor so I don't get the spark when plugging in the watt meter. I normally can leave the battery plugged in if no watt meter since I can turn the controller off. http://mgm-compro.com/pdf/en-antispark-d230808.pdf

DONE - Run lipo more often. I got a 48v MW clone coming to bulk charge. Will likely double it to 10ah for 20 mile range.

Not needed - Somewhere down the line improve my torque arms, especially the drive side which is using 1/8" steel and only 2 small bolts securing it. The 6 turn doesn't have much torque, especially at my power levels ~1000w, so it's fine for now. _Update: On wet roads I stopped on some painted stop line, stood on the ground and pulled the throttle. Maybe it's because the battery is on a rear rack, but I still had enough traction that I couldn't spin the wheel. Come to think of it, the rear of the bike is really heavy. I can pull wheelies fairly easily because of it.

- Wearing winter clothing and sitting normal cuts my speed down from 28 to 25mph, but it really feels like more than that. I hate being non-aero. I will one day have an e-recumbent low/mid racer.

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I did a brace too but if you don't jump it the aluminum post will not break I believe. It might bend but I only have 130 miles without the brace. Full suspension will be less of a snap force against the tube. I can't see why anyone would do an ebike without suspension.
 
Can I suggest? ----- Please upgrade disc brake front and rear ASAP. Otherwise your ebike looks awesome. 8)

I agree with CogHog - However, If you can make a pack box inside the bike's frame. It will give you better balance and less worry about seat post or aluminum stress breakage by battery weight.
 
Thanks Chroot. It will look much better soon.

The rack is only holding about 12 lbs. But I added the brace to be safe. Some think it's still weak, I don't.

Picking the bike up and moving it feels weird, so off balance. I really just hate the look mostly.


These Avid Arch Rival v-brakes are very strong for rim brakes. I'll do some test, perhaps with video to show how well it stops. Rain - yes I need disk brakes, but I rarely have wet weather in TX.

I did 1200 miles on my previous bike using only one front v-brake. I was still able to endo and stop well enough to not smash into a curb at the last second.

I will look into a front disk brake eventually though.

I found a $30 Mongoose Wing Comp - same frame design, on CL, should be getting it tomorrow. Needs new fork and some work, but for $30! I've got way too many bikes right now. lol
 
Carry lipo up front for sure. And you will bend or break either seatpost or rack. So till you can carry elsewhere, support the rack with some braces to the bottom of the seatpost. You've seen my pics. Steel conduit and some bolts. Easy.

You can upgrade shocks one of these days, and get the lockout controll on the bars kit. Till then, more preload and rebound.

Tuning the shocks takes some practice, just keep fooling with settings and you'll find what you like best. That rear shock especially shouldn't pedal bob that bad, with the nice linkage it has. Very similar to my specialized which has little pedal bob, unless I make it way too soft. But with full bounce, some bob is always present. Learning to pedal better helps too. I used to pedal squares when I was young and strong too. I'd hear the frame creak on a steel road bike. Never shifted out of 10th, etc. Now I pedal smooth as silk.

I try to set my suspension bikes up so the front and back are balanced in stiffness. Bunny hop, and get it to squish the same on front and back. To me, that, and stiff enough is the way to minimize the bob.
 
Yeah, the rear shock on the KHS seems to be set well as I don't get much pedal bob compared to the FSR. It's still a very soft ride.

I got this tonight for $27. Same frame design again, but with STEEL rear end/dropouts. Check out how easy it will be to bolt torque plates to that! I am a little worried about the KHS dropouts as it's soft aluminum and shaped for lightweight, not strength.
 

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Now that's a score! Easy to bolt on a pincher to that.
 
Okay, I've done another 10 miles, of real riding now on the KHS. The suspension is so great. Some roads are perfect and you don't need it 100% of the time, but 90% of the time I love the suspension. Even those 'good' roads with tiny blimps here and there - it's so much better to have the suspension. I'm not even talking rough roads, just typical good roads, they are too harsh on a hardtail and even the softtail. I really feel like I'm floating now. I can run high PSI, so I gain efficiency there. It's so fun to take shortcuts through parking lots and the bumps don't matter anymore.
The rear rack is doing good with the support arm. I got rained on this morning coming home, so now I'm really out to get proper rain gear and fenders set up. My chain is skipping like crazy though, I think it's the wrong type of Shimano chain, like IG instead of HG or something. Due to not being able to pedal hard, my performance is slower than on the other bikes, so I am going withhold judgement on whether the full suspension is the cause being slower.

My advice to anyone on the fence about full suspension: look for a good deal on a used one like I got here - $150 on Craigslist. It was dirty and needed tuning, but so cheap! The other hurdle is torque arms - look for solid (steel if possible) rear dropouts. Then there is battery mounting - even though I hate the look and handling of a rear rack, it's still worth it for the plush ride. If you run lipo then it's not an issue, but larger packs make you get real creative. I may try a mount near the front end.
 
Kinda like the old saying, once you go black you never go back eh?
 
Who needs a cargo bike to carry a bike? I had a complete steel road bike and 2 tires strapped to my backpack.

The ebike made it vastly easier as I coasted nearly the whole way, much uphill and headwind.


Now, don't get me wrong, this wasn't comfortable, but it was possible and safer than pulling it alongside with one arm.

Maybe I"m just an attention whore though...
 

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Battery is now INSIDE the frame "quadrilateral", the most ideal location possible!! SUCCESS!

It handles great and is easier to roll around and pick up with the weight centered and low. Front tire traction is better as well. Most of all, it looks GREAT, much more stealth and clean looking. There might be a few more slight adjustments with wiring and such, but this is IT! Controller seems to go perfectly where it is. Come the Spring I may place it in a spot for more airflow, but it should be fine with the cooler temps where it is. The whole setup is very secure from theft when you consider I lock the bike to a bike rack with a small ulock, so I it just about blocks any movement from sliding the battery out the way it went in. I can also easily wrap a cable lock around everything in seconds. The battery and controller were very vulnerable before on the rear rack. I also cut off about 3lbs I would say.

Now, I need to wire up my 3s lipo to it give 48v and 1000watts.


I finally have a good full suspension with perfect battery placement. Awesome!
 

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Here's a look at the nylon gears after 1200 miles of LOTS of stops, mostly at 800watts, a little at 1100watts and some at 600watts. This is the high speed (low torque) Mac 6 turn, older model. This is what happens when you run a motor at it's specifications (or below).
 

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Awesome battery mount, dude!

Also, that's about right for those gears. Mine looked like that through regular 2300w use :)
The ol' whiteys aren't so bad.
 
Thanks man, I'm really happy with the battery, it took a lot of work too. It's perfect how it just clears the crank arms, and is low enough that my knees don't hit. Great handling and looks.

I think my next step on this is adding 3s lipo on top of the lifepo4. It will reduce the strain on the lifepo4 since I won't need to be at full amps as often, but when I do, I'll have that extra 220watts. I also want to add a "rain flap" to cover everything when it rains heavy, or when parked.
 
Looking good!
 
Hit 37mph zero pedal above 30, tonight in the 40 degree air, tucked in low, can't read watt meter while riding, but I'd guess it was around 1100watts. Had the lipo hooked up, max 24amps 1189watts, likely at a low speed. It's the last ebike ride for about 11 days since I'll be away, so I wanted to make it a good one. It was mostly fast 25-32mph riding, but some slower efficient stuff too, and little pedaling for 4.2 miles. 105 watt hours, so 25wh/mile. I like the higher power because it's there if I need it, and I can almost keep the same efficiency if I am careful with the throttle.

37mph feels slow on a good straight, smooth road with no driveways or anything. Not sure why so many people are afraid of it. I wouldn't do it down a busy narrow street though.

Anyone know why my controller pulls 2.5amps more on the lipo than the lifepo4? Other than the lipo being able to output more amps? The controller was limited to the same amount. Maybe my battery bms on the lifepo4 is actually limiting it to 21.5amps and not the controller? Only one way to find out....

One thing that I noticed was with the higher speed riding, even though my controller was seeing higher voltage and watts, it didn't even get warm. It makes me think low speed 'efficient' riding isn't so efficient. The motor didn't get warm either.

Feels weird to use a bike lane at 30+ though, especially when no one is out.
 
veloman said:
Okay, I've done another 10 miles, of real riding now on the KHS. The suspension is so great. Some roads are perfect and you don't need it 100% of the time, but 90% of the time I love the suspension. Even those 'good' roads with tiny blimps here and there - it's so much better to have the suspension. I'm not even talking rough roads, just typical good roads, they are too harsh on a hardtail and even the softtail. I really feel like I'm floating now. I can run high PSI, so I gain efficiency there. It's so fun to take shortcuts through parking lots and the bumps don't matter anymore.
Glad you've got some new EV-Grin going. 8) Relating to your enjoyment of using an FS frame vs a Thudbuster & Front S-Forks... what is the high speed crossover point that the FS really helps out with? In other words, what would be the top speed you would want to ride the non-FS bike at before switching over to a FS :?:
 
That totally depends on the pavement quality. If its smooth, like new pavement, rigid is absolutely fine even at 40mph+, such as my road racer. On typical chip seal with cracks and bumps all over, then a FS is preferred at anything above 15mph, but no matter how slow you go, a bump is a bump. Are you riding a rear hub motor? If so, you really need the suspension to separate you from the weight of the motor bashing up through the bike at you. Weight makes bumps so much worse.

Overall I think a fs is a must if you don't have perfect roads. Its more complex but worth it if you can do it.

Small updates:

I got a small round bar end mirror. I forgot to put it back on last night and really missed having it today. I'd highly recommend this mirror, it doesn't look dorky since its practically just a natural extension on your bar.

I am currently installing a manual rear shock lockout/tightener using a spare brake lever.

I'm also about to add a rubber test plug to my 550lb spring, hoping to add even more cushion (such as what you would get from a big low psi tire which I can't run on this bike due to the loss in hub torque with a larger tire). I switched back to my racing saddle and realized I had no need for the cushy saddle, since the new cushy spring works so well. That is good, because I could use that cushy saddle on my road commuter. - I'm taking back these two statements. My butt wants the soft saddle and the rubber test plug was way too soft, cause my shock to bottom out with barely any weight.
 
Tonight I added my 3s lipo pack successfully with the lifepo4 main pack. It rides nearly as fast as the straight 48v 5ah lipo, but not quite since it pulls 3amps less due to the lifepo4 BMS limiting to 21.5amps. It needs more refinement with attaching it, but this little frame bag is working.

I also added a precharge resistor to prevent the spark upon connecting to the controller.

My MW clone PS unit pushes 11.4amps at 54volts, so I need to file down the shunt to get it near 5-7amps.

It's going to be nice to have those extra 200watts, up to 1000w now. It should also take some stress off the likepo4 pack as long as I keep my speed about the same as before (aside from those keys spots where I will need it).

Now the decision is: do I buy just one more 3s pack so I can get full range on the lifepo4, or do I also get 2 more 5s packs so I have the option of 48v 10ah as well?

Update:
Even with keeping the controller amps limited to below the lifepo4 BMS amp limit, the lipo stick I added in series still pumps more than it's share of amps. I did 5.5 miles today, 125 wh total, but it only took 32 minutes to recharge the lifepo4 - which would mean that I only used about 60-70 wh from it, instead of the estimate 102 wh share. This makes sense of course, because the lipo 3s pack was drained about 70% even though only 2.5ah were used. Result: I would likely need to parallel 3 of these 3s packs to provide enough run time (15ah) to match the 11ah of the lifepo4. I have one 3s pack in the mail coming, so two will probably not last that much, I lowered the controller amp setting to 21amps to help even things out.

1/21 update: Today I parked at a bike rack at a new Staples building and there was a power outlet right there! I couldn't resist since I had my lipo charger in my backpack, hooked it up for 10 minutes of 25watt charging LOL. It's nice to know there's another location I can lock up and charge at. (It's even hidden due to the bike rack being in this recessed section of the front wall of the building.

I weighed my bike today, with the additional lipo, spare tube parts, and ulock - came out to 57lbs. My next roadie build will likely come out to 28lbs :lol: :lol: I'm going to have a q100 with either 10 or 13s 5ah of lipo, and hope that it does okay on 20amp limit with careful usage. 800watts to the wheel plus my 1800w on a 28lb bike should result in acceleration that is impressive. Aiming for 0-20mph in 1.5 seconds. Will be a steel fork with torque arms to be safe. I have no idea how these q100's perform, so it will be interesting. I do know it's a 4lb motor, that's why I got it!
 
I am starting to think the 6 turn will be good, and that I do want 40mph capable, at times. Once I get my other 3s brick paralleled with the first one, my calculations say I can run 30 amps on that setup (10ah), and still only be at 6c max on the lipo, which would be pushing 60amps to make up for the 21amp lifepo4 limit.

I just got back from riding the 45mph road and wasn't comfortable riding my 36v 800watt setup, at 28-30mph. Should have used the lipo on the ride back when I needed that power. Riding such roads with stop lights is so energy expensive. If you slow when approaching a red light with cars stacked up, you will have cars running up your ass because they want to go 45 until the very last second, even when it's clearly obvious they aren't going anywhere in 4 seconds.

So yeah, I think the 6 turn Mac is good that I have it, at least with this controller where I can't run more than about 48v nominal.

48v 30amps should net me 1200watts at the tire, assuming 80% efficiency, should be good for holding 40mph on most flat roads.

My other thought is that since traffic goes in waves, I could wait for everyone to go from a red light, then go at the end so I don't have 6 cars trailing me. Bike lanes would really allow efficient travel.....I could slow whenever I want and not have to go car speed.


Small update:
Well now I have 2 sticks of 3s 5ah, so a much healthier longer lasting booster pack. Sometimes my controller pulls 21amp peak, sometimes almost 25amps peak now, it's weird like that. But today I was pulling a trailer and had a small tailwind on the fast road. I ended up bringing it to 35mph with the trailer, which surprised me quite a bit. Yeah I did hit the pedals hard for a few seconds, but it was holding that speed once I got there, on 1100w. The trailer is an anchor, except when it's a slight bit downhill or flat and not accelerating. Climbing with it sucks, but again, the bike does fairly well when on 48v compared to 36v which is when its slow feeling.

I got a 26x 1.95" Kenda Kwest new rear tire, pumped it to 40psi and I like it. Takeoff is a tad slower, but the 48v still pulls hard, still good enough and worth it I think. I was really worried about losing efficiency since I'm already overgeared as it is, but it doesn't seem to matter as long as I'm not doing big hill climbs. The ride on it is noticeably smoother and handles the rough stuff better. It surely helps take those constant small irregularities in the road. No more pinch flat worries either. It's a solid looking tire compared to the 1.5", I think a much better idea for an ebike. Oh, and I couldn't feel ANY increase in rolling resistance, which doesn't surprise me. The 1.5" would be okay for a sub 40lb bike but it's silly to ride such a narrow tire on the rear of a 58lb ebike. The decrease in torque would be the only reason I'd ever go back to the 1.5". However, I think I'd buy an 8 turn Mac before I do that.

Ride stats tonight: 9.6 miles of city riding, lots of stops, slow overall, some 23-25mph stretches, 159wh for 16.5wh/mile on an 1100watt setup. 48 degrees too, that increases wh use.
 
I met some livestrong/bontrager pros today, the one I talked to liked the ebike, thought the speed was pretty good.

It was weird meeting pros younger than me. Made me want to start training/racing again.
 
I decided that the 6 turn was not properly suited to my riding, too fast of a wind. I ordered the 8 turn high power kit from Cellman, with 12 fet infineon with 3077 fets so I can run 60-72 volts if I end up wanting to go >40mph.

Right now I just have the older 12fet with 4110 fets still on the bike. The bike performs much better with the 8 turn at my power levels (800-1200watts), and stays cooler and is easier on the controller at low speed (~20mph). 800watts on the 8T feels like 1000watts on the 6 turn, up till about 23mph where acceleration tapers off, topping out at 26mph in still air on a 36v lifepo4 battery limited to 21amps.

I also bought a 52v 9.2ah a123 cellman battery used from a seller on ES. This will go in my new FS build. Bike shown below. Should start a new thread for that bike. Nice triangle space.

That's ebike #11 now. So noobs - take some lessons. You want these things most likely:
- Full suspension bike with good triangle space and flat solid rear dropouts to mount torque arms to.
- A motor that tops out at your ideal top speed.
- A battery capable of a tad more power than you think you need. I highly recommend lifepo4 over lipo unless you want a hobby and need the power to weight ratio.
- 2" wide tires
 

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Some new stats with the 8T Mac: I seem to be getting 20wh with most riding. The only time I get worse mileage is if I WOT it with no pedal on a fast route (no efficient 20mph riding). I easily get 15wh/mile in city riding if I am conscious of energy usage, and time my stops okay. That doesn't mean I go slow the whole time. It's wonderful to occasionally WOT it up hills and yet still average 15wh/mile.
The 8T eats hills very nice on 1200watts. I flew up a hill at 22mph today with soft pedaling. Last night I was on the same hill on my road racer pedal bike, sore legs and in pain at 6-7mph. It climbs 1-2mph faster than the 6T on the same power. That's worth a lot IMO.

Ride quality is always a concern with these hub motors, so I'm going to run 20-30psi when range isn't critical. I have thoughts of a mid-drive, but there doesn't seem to be a good compact, acceptable weight motor that outputs in the 300-500rpm range without a ton of noise.
 
So with this new noseless saddle, it put me way too far forward. So check out what I did tonight. It's sooo awesome, I feel like I'm on a cruiser motorcycle, sitting low and back with my arms stretched out. It's faster because I am more aero. I still have full leg extension. It's like my bike is turning into a semi-recumbent but it's still a cool upright mtn bike. I can also do wheelies really easy. Just need to be careful with less front wheel traction.

It's like a Rans Crank Forward, but a full suspension. Badass.

I am pretty certain my wh/mile at high speed will be noticeably less. :D :D :D


3 hours of engineering work = well worth it!

Of yeah, this Ergo Seat is awesome, even by itself. Highly recommended. It lets your beans float freely and not being hit on every bump.
 

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[/quote]

You know, there are a lot of complaints about rear QR racks breaking, frames breaking at the seat posts, and so forth with just batteries sitting on them like that. With the extra support.. that looks suitable to hold maybe 50-70lbs at most.

Also putting the rider weight that far back is not good for handling. You can also very easily do wheelies with pretty much all the weight on the bike biased towards the back. icecube57 broke his arm ( or wrist? ) from a fall by doing an unintentional wheelie. He's a heavier dude, but wasn't as far back as you are.

Wear a helmet :p
 
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