Good news - I can take my bike apart!
 

Bad news - putting it back together? That's not working out so well. I hope you folks can help.

Background: I have a Downtube Mini, this is a folder with 16" wheels and a Sturmey Archer 8spd IGH. This is the first time I've attempted to remove and replace the rear wheel on my own. I'm doing this in an attempt to install the "Nirvana Suspension Mod" (replace the coil spring with an elastomer)

Anyway, I got the rear wheel off OK, did the mod, attempted to put the rear wheel back.

Problem #1. The axle on the chain side does not extend far enough past the fork dropout to screw on the nut properly. Here you can see the right side nut is off, and lying on the carpet. http://img515.imageshack.us/img515/8951/img3444.jpg

Here's another look at the right side:

http://img411.imageshack.us/img411/4329/img3445.jpg

Second problem; getting the shift cable back on the hub. Should just be the reverse of what I did to take it off, right? Right?? it's not easy!

Any help you can provide would be much appreciated. Thx!

To reinstall the shifter cable, make sure the shifter is is in the position which allows maximum cable length. If the hub spacing did not change with the installation of the mod there shouldn't be any issue with reinstalling the wheel nuts on the bike, I see 3... maybe 4 threads on the drive side axle.

Show us the amountt of axle protruding from the left side. Remove the nut and show us the pictur.e

More pictures. Here is the side with plenty of room to thread the nut on. (bike is now upside down; I don't have a workstand)

http://www.bikeforums.net/attachment...1&d=1247831497

Here is the side without enough room. Despite the 4 or 5 threads showing, the nut threads on a tiny bit but doesn't tighten.

http://www.bikeforums.net/attachment...1&d=1247831513

Side question, the locking tabs you see in the picture. Should the tabs be facing toward the front or back of the bike, or is it irrelevant?

Thanks!

Locking tab position is irrelevant. You also could get away with only one anti-rotation washer if that would help. I'm curious as to how the wheel used to fit and now doesn't. Is there something in the conversion to a suspension that caused that to happen?

To move the axle over you should be able to move one of the flat nuts from the chain side to the opposite side to get a little more exposed thread. SA8 hubs are actually very narrow and the way to get a wider over locknut dimension is to stack up thin locknuts.

You can also remove locknuts and use the anti rotation washers in their place. The washers would go inside the dropouts and that would expose a lot more thread.

Does the axle protrusion measure the same on each side. From what I can see, it looks like the 28 spoke version which means it's a 155mm axle and it should have 19.5mm protrusion on each side. If the protrusion is not equal, something must have happened to make it that way. I confess limited knowlege of the internals of that particular hub, but as far as I know the shift mechanism is external to the axle unlike the 5 speed, but I still don't know the effect moving the axle endways would have on the shifting cams.
The only immediate solution I can see to your problem is to sacrifice the drive side anti rotation washer to give the nut more room to bite, but I hesitate to recommend that because I cant say with certainty that 2 is overkill.
If the axle protrusion is unequal,you might try contacting Dave at Sun Race/Sturmey Archer, contact info here.
http://www.sturmey-archer.com/contact.php
I have not had any luck with e-mail, but he does return phone calls.

Thanks for the replies. The suspension conversion was swapping out a coil spring for an elastomer, all of this was done in a different part of the frame and I'm sure it had no impact on the axle spacing. I removed the rear wheel to get sufficient clearance to work on the suspension.

I'll measure the axle protrusion and ensure it's 19.5mm on each side. I can't imagine that would have changed. I've never removed and replaced a rear wheel that wasn't a QR before, so my guess is that I have some washers in the wrong place, or I don't have the axle lined up just so in the dropouts, or maybe I just need to muscle it into place and get the nuts back on one way or another.

Looking at your very first picture, it looks like your entire wheel is offset to the left. It actually looks like the tire is rubbing against the frame. Also, look at how the brake arms are at different angles.

If I had to guess, a spacer washer somehow migrated from the left to the right.

A couple hours of messing around with the wheel, and it's back on the bike!

http://img190.imageshack.us/img190/1503/img3456j.jpg

I think it may have been caused by the way I had the chain tensioners positioned on the axle. They are asymmetric, so they need to go a certain way or they'll skew. Once I got that sorted out, I was able to hand tighten both sides, and wrench tighten them to a relatievly low amount. I am afraid that if I really increase the tension, the chain side nut will pop off.

You can see the dark green elastomer in this picture. I'm not going to reattach my rack or fenders until I'm sure I like the new suspension.

I'm a bit afraid that I may have some lurking safety issues after the wheel removal/replacement; the brakes are not 100% lined up properly, and I don't know if I have the rear axle nuts tightened sufficiently for safety. May still need to take it to the LBS for a full checkup.

Thanks to everyone who contributed ideas and advice!

Just wondering - why did you want the elastomer over the coil shock?

The chain tugs are your problem.

They have a correct orientation and an incorrect orientation. If there is not enough axle leftover with the correct installation then don't run them. They don't do anything anyways. Just creates extra steps in removing/reinstallingn the wheel.

The coil gives a bouncy ride, and the elastomer should dampen that out. I've heard good things about the elastomer mod on this site from those who have tried it.

The downside is that years from now that elastomer will turn into a ball of goo. Please, save the original parts.

Oh alright. Makes sense. Wordbiker has a point though.

Good: You can take your bike apart.
Better: You can put it back together.
Best: You can put it back together with no parts left over.:D

Good to know. I'm saving the spring anyway because I'm not sure I'll like the elastomer. New elastomers are $15 from Birdy so no big deal if I have to replace it one day