Bike plans 4 summer

nutnspecial

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I had planned on a big road trip (in a car, camping)- still might, but can't leave yet. Otherwise pretty much caught up.

Soooo, I'm thinking it's time to let a bike 'go', (and replace with 2 more) :D

Goal 1: 2wd Utility hauler, tractor like, lowest cost possible.
Good torque 0-20mph, reliable/quiet/stealth and not too heavy.


I have:
1kw front kit
12s 16ah battery

I need:
Bike -$225
1kw rear kit -$200

fat.jpg

Rebuild fat wheels reusing rerolled spokes with hozan threader. Will put a big rack on it and may have a spare set of hydro brakes to throw on as well.
Cost out of pocket: <500$
Total cost: <900$

I'm afraid it still might weigh 100lbs?


Goal 2:
Retire the Klein mantra (my sig). I'm so happy with my creation and if I had the room (and money) I'd keep it around, but I should move on to something sturdier.

Steel frame, double crown, 19" shinko 241's.
gross.JPG
I had planned to try a bigger motor but it makes more sense just to move everything over. Lots of work and I will miss the klein I'm sure.

I have: almost everything lol.
Mostly custom work and will try a new hopefully sturdier rear dual FW hub w/ sealed bearings. Gonna try to gear it for 30-35mph on 24s/60-80a, but might start with stock gearing of 42mph.
Afraid it will weigh 100lbs, but at least it'll be HD and 7kw capable.
 
You've seen karls fat bike builds on his blogs? Most are mid drive, but it will get you an idea of what to expect and what the potential challenges are...

I love the mantra. Isn't there some way you can get the batteries in that huge top tube? I can do a lot with 20-30 18650 batteries...
 
seen karls fat bike builds on his blogs
Nope, could you point me in the right direction?

I found this build in progress: Converting a FAT-BIKE to electric for off-road use

And this wheel build info, unfinished: Anyone successfully spoke up a fatbike wheel?

Thanks, I love my mantra too (anytime I get a minute or two away and come back to it lol). That's a great idea for a stealth build (for someone confident to modify the mantra 'fuselage'), but wouldn't work for my power requirements. When I tear it down it will either go back non-electric or get completely retired.

I posted on the 'convert for offroad' thread I linked. Fatbike and kit on the way- fingers crossed it goes as planned, (and isn't too much of a pig) hahah.
 
Bike and kit happened to come on the same day, in good order.
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Once I figured out I had the fork backwards (lol) the bike is pretty neat. Like a monster truck bike or something, they still seem ridiculous to me, somewhat novelty. Electric's kinda a novelty too, so maybe a good match.
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I'm thinking of taking the >1" of stem spacing off and cutting the fork, and probably cutting down the 29" bars a little. Everything seems acceptable, but I have some DH quality hydros and pedals to replace what's weakest imo. Will probably get bigger chainring eventually too, for pedaling full speed of maybe 28mph.

Btw. 36h rims. 135 and 190mm dropouts. 110mm BB for Mongoose 'Hitch'
So I can reuse the rims without redrilling, whew. The rear motor will literally be a squeeze though- 'wheel' see lol. The bike def feels under 40lbs. Ship weight actually said 30lbs!!!!

These kits are really nice. Can't beat 155$ with a damn stick.
kit1.jpg
kit2.jpg
kit3.jpg
kit4.jpg

Now I have to figure out how in the hell to get these spokes to the RIGHT size and get these wheels built!
 
Tore the wheels down and decided the 14 (or 15g) mongoose spokes were way too small for the motor. Enlarged and angled rim holes for the 13g motor nipples, but the darn spokes are about 6mm too short for 'one cross'. Verified and dialed in the right size on the simulator (http://www.ebikes.ca/tools/spoke-calc.html) so I could order some, since even if I wanted to make use of these short ones by lacing radially hozan threader can't rethread 13g.

Wow 70 bucks for spokes- bummer one of the old sets couldn't be reused!

If I had an aluminum bar and/or seatpost I'd throw them on, but so far looks like the avid hydros will work well, along with a used sram paddle shifter, and some DH metal pedals. Seat's not bad after modding the clamp so it's back a little further.


==========
Couldn't get the rear avid caliper to take back it's pistons 4 new pads, so released the 'fill' (bleed?) screw and they went in. Now it doesn't get hard tho lol. Dammit, prob have to bleed.

The rear dropouts will have to come in 10mm each, I wonder if I should use heat or nah? Preferably no, cuz paint, but whatever works without chopping and welding. The rear caliper will also need a huge mod inward for the hub, looks like. Gee I hope the 2x 1kw hubs are worth all this trouble :lol:

!2s 16ah easily fits in the triangle in a bag. Don't know WTH the bag came from and it'll never last so I plan to use the bottle holder screws/holes on downtube for a bracket to help wedge it up tight and take gravity pressure off straps.
 
Hey Nuts, looks like I'm on a similar path as you. I was kind of thinking the fat bike thing was a bit of a fad/bad joke but my curiosity got the better of me. Well I am glad I did it now. These things are a lot of fun.
If I was limited to only do one change on my fatty it would definitely be tires. I know that the best fat tires are like double the price of good DH tires but they are so much better than the entry level tires that come standard on a cheap bike.
I put a pair of Schwalbe Jumbo Jim 4.8s on my bike and the difference they made to the ride was amazing. Worth every cent IMHO.
I'm a bit worried that your dd hub might get a bit hot during long slow climbs, this was why I went for a Bafang 750w geared hub. I ordered the cassette version so I could throw my 10spd 11-42 sunrace cluster straight on. They also come with 190mm dropout spacing on the axle so it should fit straight in.
Oops sorry I missed that you are doing 2wd which should keep the heat in check.
My costs are a lot higher than yours so far all in AUD,
$699 Wheeler Savana fat bike
$50 Sunrace 10spd 11-42 cassette
$195 Luna Lander fork + $77 shipping
$240 Pair of Schwalbe Jumbo Jim 4.8 tubeless ready
$50 Venzo DH stem and h/bar combo
$645 Bafang 750w 190mm cassette geared motor kit from Conhismotor
So just short of $2k and still no battery, I will just use my old faithful 12s 15a/h hobby king lipo pack to start with.
Any ways sorry to hijack your thread just thought I'd share the fat love :lol:
Good luck with your build.
 
With the widest tire profiles that fat bikes offer, you never really have to worry about "will it ride through X & Y terrain". My Surly Ogre can only fit 3" fronts & 2.5 rears (I've been able to just barely squeeze 3" rears) but there are some local areas and terrain that my bike seriously struggles to the point of unrideable, even with electric :| . Sometimes I think a wide profile bike is a better choice because you can always just setup using 3" midfat or 29er wheels for most situations, then switch up to the fatter wheels when the need arises. And with middrives, changing the wheels is an even easier process.
 
Yes to both of your replies, agreed and thanks! I guarantee my hubs will take a little from a true 'fat' experience, gauging from just 5 minutes riding it unpowered, (or even generally, when comparing hubs to mids). My reasoning for hubs is cost effectiveness/maintenance, and overall appeal/popularity. My first bike is def for me, but a cheap fatty with easy going hub motor(s) is more appealing to the vast majority. I want a nice (and different) stable (and non-lethal) 2nd ride that random people and friends can also ride. It's gotta have the wow factor for the non ebikers, but while being a decent cost with the smallest pita for them firsthand and longterm.


Got the rear 1kw ebay hub on with brake and FW/deraileur (in 190mm d/o). Not too bad. Cuz steel frame. Pics incoming
 
yojimbos garage on ebay had super service and good price. I ordered the 168mm 13g spokes on saturday and they shipped on monday! Gottem in hand now and excited for what should be some easy wheel building.
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One problem. Turns out the hub used 12g :lol: I was lazy and went by eye assuming spoke size, and will be paying for it. I can't reuse the nipples with these, and they're a little sloppy in the hub anyway. Anybody want some 168mm 13g spokes :oops:

Gotta confirm what I'm trying to replace are actually freakin 12g
 
One other problem, it seems like building with a motor and this 100 rim and 12g spokes, really sucks.

And it sucks even more when you think a more complicated lacing method will help :lol: get the rim to start pretty tru and be easier to finish. Alternate single cross swapped looks kinda cooler than single cross and should be stronger, but a it's a huge pita to dish for nipples, it didn't help the rim start out straighter, and it's backwards to tru. To the moon, alice!
 
Why so thick spokes? Thick spokes in a weak rim will result in insufficient spoke tension and you will break spokes from fatigue in the "spoke-elbow" after some time.
Reason is that a spoke that isn't tensioned enough will lose the positive tension momentarily during different riding conditions. For example hitting a bump or pothole.
Same as bending a piece of metal back and forth.

How did you deem the spokes too thin? Especially when they were mounted on the rim in the first place? I would guess a fatbike rim is quite flimsy.
 
Wheazel said:
Why so thick spokes? Thick spokes in a weak rim will result in insufficient spoke tension and you will break spokes from fatigue in the "spoke-elbow" after some time.
Reason is that a spoke that isn't tensioned enough will lose the positive tension momentarily during different riding conditions. For example hitting a bump or pothole.
Same as bending a piece of metal back and forth.

How did you deem the spokes too thin? Especially when they were mounted on the rim in the first place? I would guess a fatbike rim is quite flimsy.

Good thoughts about spoke tension. I manged to break a few spokes before I started to spend more time checking the tension. Because of the weight of my bike I still break a spoke about once every 700 miles of riding.
 
IDK about hub motors that much, but the 13g spokes were awful sloppy in the hub. The 12g even seemed a little smaller than the original hub motor wheel, but they seem to have worked great. The pattern got super strong. The rims being unwelded gives a good idea of how rigid they are as well. Light but really stout, and I got real good spoke tension. We'll see!

Thanks chas I will read up!

I'm sure I'm gonna like this bike alot, and finally I'll stable a second (more versatile and easy going) bike for friends/fam. Just got to get some time to get her done. Remodeling office, and shop; while I'm in the middle of a handful of unexpected jobs/work.
 
My ideal setup is 2 or 3 ebikes for different moods.
1) High powered rear direct drive motor like the MXUS 5K, laced into a 17" motorcycle rim and an Adaptto controller, or a cheap 24fet trapazodal on a full suspension mountain bike, 2.5 tires.

2) I currently have a rear MXUS 3K V2 4T laced into my Crystalyte 26" with 18fet Sunwin cont which would be placed onto my Townie.

3) High powered mid drive, FS, Lightning Rods kit or similar.

4) A MAC geared front hub motor for any one of the previous bikes, to make anyone a 2wd.
 
If you noticed above, I want to try open dropouts with no arms or plates.

Essentially, I welded 'plates' to the weaker finger of the d/o, carefully flattened any high spots, and have a tight fit for axle. The plates are for mounting the racks too. I wanted to spend a little time on fit/finish since the rack mounting hardware is so generic, and wanted fast/easy wheel removal/install that didn't require arm/plate/rack removal.

Looking at the pic, does anyone see an issue? It's >3/16" mild steel. As long as the axle nuts are tight it should be pretty bombproof right?

Here's a better pic
View attachment 1do (3).jpg


I also went a little power hungry and ordered two 18fet controllers from aliexpress. 60$ shipped!!! Idk what amperage they'll be, probably at least 40a /pc, so < 2kw per wheel. Will try the stock 12fet controllers first- I did solder both shunts but it didn't make a crazy difference on the last install.
 
I have been contemplating something similar Nutspecial, however wouldnt it be better to have that "cap" (on the end of the fork) have long arms that go up either side of each fork finger. Kinda like this --> IiI IiI
if "i" were the fork finger itself. Or shall I say fork leg is better suited.

This will make it lots stronger.

The reason I was thinking of this is because of my BMC V1 geared REAR motor is 135mm and to put on a front fork which is like 110 or 100mm.
 
The 18fet controllers came and man they're big. I think I can hide them under the racks though. Paint em black. But how much do they draw? Am I going to be surprised by two of them with two motors? I mean, my Klein only has ONE 18fet, and even at 18s 60a it's a handful. . . But I think hub motors generally lack torque, even when geared for the same speed?

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Anyway, home stretch. Deciding whether to run the modded stock 12 fet or new 18fet, and where to put them. Battery in triangle bag done. Holds tight with one water bottle holder screw, three bag straps, and aluminum bracket inside bag. Kinda getting excited, this thing will be a beast!

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I think it would be ultra cool to have a wide ass fat rear tire but a moto rim and moto tire, and not the standard 1.60 but more like a 2.50 moto rim/tire, but a regular 2.5" mtb front.
I was thinking about that today e-biking my usual 40-50km. I saw a big mound of dirt, sitting there for the past several years, so its settled nicely. I'd say its 2.5 stories high. Even if I had to go up it at an angle, I am tempted to do it before the houses are built in its place. Which means I need to get on fixing my MXUS 3K and seeing its limits before purchasing the MXUS 5K.
 
All idea's for now Nutspecial, I always have lots of idea's.
The next move I am going to make, is getting more capacity in my 24Ah battery. I will do up another brick of 12Ah and I should have less range anxiety. I ran out of juice last night, and found it hard to find a suitable outlet. My usual spot was taken up by someone using their cell. That spot, grocery store patio with tables chairs + outlet, Starbucks inside spitting distance away, some yuppy grocery store hot food line with a manager that had a curled up pony tail. Yuppy indeed.

My usual plastic container broke last night, lost a few things but I heard the charger and U lock fall over my ear phones. I may try to go back and find it today. But first I am going to Princess Auto (harbor freight) to snatch some large ammo boxes. I ordered some 42L pannier bags from Chain Reaction Cycle so that should take by Tuesday to arrive. Just got 2 ebikes on the go now.
 
I might not have linked my thread for 2wd throttle? https://endless-sphere.com/forums/viewtopic.php?f=3&t=89091&hilit=+custom+throttle

Well, I went to open it today, and one of three inner retainers borked, along with one of the magnets/holders. I was afraid of that when majorly effing with the cheap throttle. Summer heat adds to the rage heheheh. . . . but we will build it bigger, we will build it stronger- the 72 MILLON DOLLAR MAN will be coming :?

Nah, I'm glad boytanstu showed us those throttles and I bought one. half twist with key and voltmeter for <10$. Will hopefully work awesome. fyi, 3 spd switches can fit 2x micro on/off rockers. . . possibly for controller selection??? and I think I can nudge a small button switch into the actual 3spd switch, wired dual, for a 'front speed limit' function. should be pretty clean, function, and simple if it works. Got all the logistics done and worked on modding the new controllers this morn after frocking up the throttle. And also frocking up my new one lol. Was not thinking and burned the hall with 45v lol. Hall replace or wait for new throttle. . . :twisted:

pics incoming build incoming. I think 2wd, 2x 18fet, w/ 4" tires should be interesting. Why have I not seen video of such a simple thing yet? I must not be looking hard enough no doubt.
 
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