Built an e bike. Is it okay fir the axle to sit in the dropouts like this after being torqued down?

[jlm]

So i built a 3000w e bike (still upgrading certain things.) And when i initially get the axle into the dropouts its perfectly vertical. But then once i torque it, it moves a bit. And then stays there during and after riding. Is this okay as long as it isnt moving? (Torqued to 50ft lbs by reccomendation by the way) Thanks.

 

[Chazmo]

My Fättie has these washers with tabs (see middle of picture) which lock the rear wheel into a fixed position within the dropouts. I’m not sure if you’re talking about the rear or not (a picture would help), but I would think that the key issue here is proper alignment of the disc plate within the disc pads.

 

[jlm]

I see. I think that peice would help a lot actually. And yeah id like to add a picture but for some reason it will not let me. Thank you

 

[Chazmo]

I’m not sure what these tabbed washers are actually called, jlm, but good luck!!! Again, I think your only issue here without them is whether your brakes are working properly.

 

[harryS]

Sure would like to see a picture. They won't post if they are too large. You have to shrink them,

Usually, the axle is pretty snug in the dropout. It might rock a little, but you shouldn't see any spacing between the axle's faces and the dropout, Certainly shouldn't see it turn much at all. I guess you could put a wrench on the faces of the axle as you tighten the buts to keep it vertical, but you shouldn't have to do that,

Is this a rear wheel? Big motors can be problems on front forks.

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[jlm]

Yeah its a rear wheel. Id like to put a pic but it wont let me!

 

[Jeremy McCreary]

Yeah its a rear wheel. Id like to put a pic but it wont let me!

If you haven't already, reduce your photo file sizes to under 2.0 MB, then try again.

 

[Base]

I’m not sure what these tabbed washers are actually called

Non turn washers

 

[Chargeride]

It will be fine, just keep checking the nuts.

 

[Chazmo]

Non turn washers

Thanks, Base. Learn something new every day… ‘specially around here!

 

[harryS]

Here's an example of a not so good install. This ebike axle is 12x10 mm, and the normal bike dropout slot is cut for a 10mm axle, meaning the motor sits a little high. What a lot of people do is file the slot and the derailleur guide about 1 mm deeper, so the axle nuts will fit over the old marks. Otherwise, you lose too much of the gripping area of the flange on the nut.

This is a pretty good frame for a motor because it has a lot of metal for strength. When an alloy frame is files, the cut area has to be rounded like the original to prevent cracks at the corners.

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This by the way was my first ebike motor install ten years ago. I proudly posted it in a bike forum and some busybody like me said the alloy frame looked too weak. What do I know. Nothing. Well, I moved that motor in a steel frame and never had any problems. In hindsight, the blue frame was a bit fragile, and I eventually installed a mid motor on that bike,

Anyway, a lot of this is common sense mechanics. Make sure your fasteners have a good grip. If nothinbg can move, should be OK. I mark the nuts against the washers with indelible marker. Makes for a good visual check.

.

 

[JRA]

For use with other than low wattage hub motors the tab washers are basically useless for most installations due to the bikes dropout structure vs. the potential torque output of the motor, especially one over 1,000w. But there are plenty of aftermarket torque arms available that will connect the axle to the chainstay reliably.

 

[Chargeride]

I ran a geared hub at 2500w using them, pretty hard riding, never had an issue, you just need to use diy spider senses, ride it hard then have a look how the dropouts are coping

 

[Chazmo]

For use with other than low wattage hub motors the tab washers are basically useless for most installations due to the bikes dropout structure vs. the potential torque output of the motor, especially one over 1,000w. But there are plenty of aftermarket torque arms available that will connect the axle to the chainstay reliably.

View attachment 193288

Actually, JRA, My fat bike has that as well. Well, something similar as well. Cool.

 

[PedalUma]

If it is a 3 kilowatt motor it requires two torque arms. I have even seen 500W motors spin the dropouts and wreck frames.

 

[Chazmo]

If it is a 3 kilowatt motor it requires two torque arms. I have even seen 500W motors spin the dropouts and wreck frames.

Wow, that’s kind of surprising to me. But then again I’m used to my Fättie which is so VERY overbuilt that I can’t imagine that’ll ever going to be a problem. At least it seems that way to me. Didn’t stop the front fork crown from shearing off (metal fatigue)… I’ll keep crossing my fingers.

 

[PedalUma]

Wow, that’s kind of surprising to me. But then again I’m used to my Fättie which is so VERY overbuilt that I can’t imagine that’ll ever going to be a problem. At least it seems that way to me. Didn’t stop the front fork crown from shearing off (metal fatigue)… I’ll keep crossing my fingers.

The fork crown sheering off is hugely dangerous. I guess it goes to show, whenever doing a tune, wash the bike and inspect every bit of the most important parts, the frame, fork, and wheels. Then get into stuff like the headset, drive train, and brakes. Tires are also hugely important, only about the size of a coin is ever providing rolling and traction at any given time per wheel. You are riding/balancing on a dime. I mostly, 99%, do mid-drives of up to 90Nm. I have a 2019 motor apart right now and am giving it a heart transplant on the operating table. It started slipping internally.

 

[Chazmo]

The fork crown sheering off is hugely dangerous. I guess it goes to show, whenever doing a tune, wash the bike and inspect every bit of the most important parts, the frame, fork, and wheels. Then get into stuff like the headset, drive train, and brakes. Tires are also hugely important, only about the size of a coin is ever providing rolling and traction at any given time per wheel. You are riding/balancing on a dime. I mostly, 99%, do mid-drives of up to 90Nm. I have a 2019 motor apart right now and am giving it a heart transplant on the operating table. It started slipping internally.

Absolutely, PedalUma. First of all, I chalk up the fork breaking to the crappy materials/fabrication that were used in the cheap fork that was standard on Fättie. No amount of preventive maintenance / care of the bike would’ve prevented its failure, although a careful inspection might’ve uncovered the failure before I went out for my ride… Lesson learned.

Clearly, the lousy fork is one of the ways that costs were kept down on my otherwise extremely rugged bike (which I love to death, by the way). And, at least the bike held together with the broken fork on it. I was hearing and feeling odd things in the steering for several miles before I actually realized what happened. I was able to ride home anyway (at least three miles from where I realized the problem), but I didn’t take on any twisty terrain at that point. The scary part is that it was already broken when I was hammering down a fairly steep downhill and I didn’t know it!

 

[PedalUma]

Last week on a green bike, not a red one, I used this technique to install a 13.2 mm axle into a 10mm dropout. Because I am a Swede my ancestors learned how to get large things in tight places or they would have died off in one generation. Here is also the toolkit to do it.

 

[kevinmccune]

Yeah its a rear wheel. Id like to put a pic but it wont let me!

been there done that,my used phone will not send you email or anything for that matter.