- tip for installing rear wheels-

[waynebergman]

swing arm spread.jpg

(78.86 KiB) Downloaded 2 times

I have found spreading my chain stays with tie down straps anchored to the sides of my pick up truck like shown in photo is a real help for installing the wheel. I have the usual assortment of axle spacers and washers and what not for both my HS3540 and my new little Mac 10t rear hub motors and I have struggled with trying to cram all this width into the chain stays that seem to be too tight of a fit. Its always been a chore to squeeze these wheels in place. After a lot of frustration I have now found this to be a smooth solution and thought I would share it for what its worth.

Can someone help me please with why my photos are not uploading. I have used the place inline function and thought that would do it but I see it is just a link in this post

[amberwolf]

The photo is uploaded just fine--it doens't display because it is too wide. I think 800 pixels wide is the max it will take before it just linkifies it. Can't remember for sure--mihgt be 600pixels.

[marty]

Reduce image size to 800 x 602 pixels

swing arm spread800.jpg (140.55 KiB) Viewed 300 times

[dogman]

Cool trick. It can be a bit tricky to tweak the dropouts from 135mm to 140mm when you try to install the wheel.

If you don't have a truck, maybe do something similar with an opening, like a gate to the backyard or something. Or a box frame made from some 2x4's.

[MadRhino]

My logic of proper mechanics doesn't like to spread the dropouts to fit the axle.
I guess it has little consequences with steel if the dropouts are corrected to be parallel, but Alu sure weakens when treated like that.
I prefer to mod, to make a perfect fit. Quick servicing ability and proper alignment are a must for me, for I like to swap the motor wheel at will. Having different motors mounted in various wheels and tires, is the best way to quickly adapt to ever changing trails and riding conditions.

[cbr shadow]

I would think it'd be hard to get enough torque to spread steel forks just by using straps like that.. I've never done it though so apparently it isn't! Cool idea!

[cbr shadow]

Do the forks generally pull evenly? Meaning that if you want 135mm spread to be 140mm is it hard to get each side to move 2.5mm?

[waynebergman]

mac 10t LR.jpg (46.06 KiB) Viewed 201 times

I don't think it matters CBR if they are spread evenly. I just spread the chain stays apart until my wheel assembly will fall into place with out having to push and pull things around with the 3 hands I don't have. I have two hubs sets that both need spacers to move my chain stays outbound from there relaxed 135mm state for a couple of different reasons. Maybe others have bikes that these hub motors just slide into place but for me its a real bear to do this job by yourself with out spreading the stays with some kind of 3rd hand. Since I started working on this e-bike project I have taken the wheels off the bike and reinstalled about 50 times and so far I have found this to be the easiest way for me to get the wheel in place.

[john7700]

I got so sick of fighting with my rear wheel that I finally cold set my steel
frame so it is big enough to accept the axle. Dog tracks a little but worth
it not to have to fight with the wheel every time.

[Samd]

What about some all thread rod with two nuts placed between the rear dropouts, then the nuts screwed apart evenly (washers to help friction)?

[John in CR]

What about some all thread rod with two nuts placed between the rear dropouts, then the nuts screwed apart evenly (washers to help friction)?

A permanent spread such as by that method is called cold setting, which is a big no no with aluminum. Flexing it some is OK such as with the straps in the OP, but I agree with MadRhino, ie mod the axle for a proper fit.

[Punx0r]

Other than cast, what's the problem with permanently bending ally?

Repeatedly flexing it will certainly cause failure through fatigue, but I think it'd have to be an awful lot of cycles before failure occurred.

[dogman]

To clarify what I meant at least, I feel that a "tweak" of the frame on alloy is safe. 5 mm more, to 140mm is only a 2.5 mm bend per side. I've seen alloy frames flex more than that because I pedaled that hard. Seems relatively harmless. It's just flexing the metal, not bent enough to be permanent and thus not creating a crack in the alloy tube.

But the problem is if it takes two hands to spread the frame a few mm, which hand drops the wheel in? Not everybody has a wife handy, or if you do, she may be off working to make the house payment as she should be.

So this method looks handy to pull the frame enough to easily slip in the wheel, along with that 2 mm of spacer washer that makes your disk caliper clear the motor housing.

On a steel bike, you can cold set the frame with much much much less risk of causing a crack that fails later. On my dirt bike for example, the frame is cold set to about 145mm, and I use the nut on one side to pull it back to the 140mm I have with my spacers. I just stood on one dropout, and pulled on the other to bend out the steel a tad. Cheap frame, so it bent easy as pie. On real cromo, I'd want to use the threaded rod to bend it more carefully.