Help with GT RTS rocker play

[Tootyred]

I don't think your bolt is hugely short of shank, looking at where the bearing was sitting. Maybe a few mm. I was just concerned the thread looked quite close to the wear mark for the bearing given the gap the other side to the head.

As said above the thread will only be a tiny bit smaller, but when you start adding up a tiny bit here, tiny bit there, suddenly you have a sloppy mess!

You could....as people have said be getting both horizontal and vertical movement in small amounts.

 

[ishaw]

Sorry for the delay, not had much time on my hands of late to get to the shed.

I've pulled out some of my spare bits, and it is clear to me what the cause of the play you mention it. Basically you've no meat on your bones. Here's a few pics of a couple of different rear ends I have. You can see a pronounced area where the rockers fit on mine, yours are worn flat.

I've also added a pic of the stock bolts (I think). They only have a small shoulder and mostly threaded. I'm sure a longer shoulder would be much better if you can find one with the thread in the right place.

So your washer fix should in theory compensate for the wear to your rear stays,.

 

[ishaw]

I've actually been a bit of a tool. Pics are of the rear end, not the BB mounting point. I'll grab a pic of my spare frame tomorrow to see what that looks like.

 

[Kieran-b]

It would actually make more sense if there was a shoulder on the BB mounting point because it is the centre part of the bearing that rotates so there needs to be some clearance to enable the bearing to do what it is designed to. You can see where the bearing has been rubbing against the mounting point in my photo.

I'm now thinking that if everything I have is correct then this play is down to the design / choice of components and the solution at the time was simply to tighten the bolt up a bit more. And mine just wasn't tight enough.

Using bolt with a longer unthreaded section and cutting it down still seems like a good idea as it would be good to put a new bolt in there anyway and would surely be better if one bearing wasn't sat on the thread. It has given me a slightly different idea however, which I'm going to try first.

 

[novocaine]

I'm not convinced they are the correct bearings. To further spoil the pot, early rts has a bushing there that a fair few folks replaced with bearings but often with normal 6008 bearings instead of the radial bearings that were used on later RTS frames. When ypu did that, you needed the shim either side to prevent the outer race rubbing.

 

[ishaw]

Another thing I've noticed is that the rocker bearings stick out a lot in your pic, mine are flush with the rocker outer. Has this perhaps caused the frame mount to get worn?

Here's a pic of the radial bearings that I have and also some NOS top hat bushings.

These are used in the main frame pivot, and can of course develop play when worn

 

[ishaw]

Here's a pic of the BB area of my ears I'm converting to disc. It is pretty flat, well absolutely flat where the rocker bearings would sit

 

[Kieran-b]

Another thing I've noticed is that the rocker bearings stick out a lot in your pic, mine are flush with the rocker outer. Has this perhaps caused the frame mount to get worn?

Here's a pic of the radial bearings that I have and also some NOS top hat bushings.

These are used in the main frame pivot, and can of course develop play when worn

Thanks for this. Yes, it does look like my bearing is stuck out a little. There is a little movement in the pivot too so I'll be looking at that next.