Xtracycle rear cassette problem

[dequinox]

Not too many people are watching my build log, so I wanted to post this problem specifically:

https://endless-sphere.com/forums/viewtopic.php?f=6&t=101548

See the last post. The 7-sprocket cassette on the rear motor I have would cause the chain to rub on the frame.

Any suggestions? I thought maybe just limit it to 6-speed and remove the smallest sprocket, or maybe attempt to spread the frame a bit.

[img="https://endless-sphere.com/forums/download/file.php?id=270843"][/img]

 

[Voltron]

You need to add one or more of these...

to the axle, until they stick out past the rotating part of the freewheel.

You can use something like this....

if it needs a lot of spacing, but it should have the flat sided hole kind in there first.. Round hole ones sometimes push over the stop where the axle flats end when the axle nut gets tightened.

 

[amberwolf]

and don't use the thin (<1/16") doulbe-d-hole washers, use only the thick (>1/8") ones. thin ones will deform over time, and both allow the nut to loosen and the axle to move in the dropout. two thin ones will *not* do the same thing one thick one does. :/


btw, the smallest sprocket is often the lockring, so you typically can't remove it. (unless you can come up with a different lockring)

 

[Balmorhea]

If you have the necessary tool to remove the freewheel, you can substitute a 6-speed freewheel with the same overall range. If you have index shifting, you will need a 6-speed shifter to make it work.

 

[dequinox]

This is what I needed. Thanks folks. I believe the kit comes with a set of 2x D hole washers that are 1/8" thick. It'll be a bitch to stretch the frame every time I want to change a flat, but whatever we have to do right? I'll give permanently stretching the Xtracycle sub-frame a try. I'm not sure it will move much though.

I'll keep a 6-speed as my "plan B".

Thanks!

 

[amberwolf]

I'll give permanently stretching the Xtracycle sub-frame a try.

regular rear hub axle.

nuts threaded on to go between the dropouts, rather than outside.

thick flat wide (fender) washers just outboard of the nuts.

insert axle into dropouts, hand tighten nuts so washers press against inboard side of dropouts.

use wrench to turn nuts a turn at a time or so, until dropouts are just past the width you need them.

loosen nuts, and remeasure dropout distance, and repeat the above until they have been cold-set to the correct distance.

it's not perfect, and it will not keep the dropouts perfectly parallel to each other. depending on the strength / etc of each side of the frame, it may not spread them evenly, either...but neither will having to force the wheel into the dropouts each time, and it's way way easier to do this now than the other every time you work on the wheel.

 

[dequinox]

[/quote]
regular rear hub axle. ... easier to do this now than the other every time you work on the wheel.
[/quote]

Thanks Amber, this is solved. I used a pair of old-school twin-screw woodworking clamps to stretch the frame. Wheel fits a treat now!