1st motion bearing circlip 22g851
Turbo Mini Forums

I have rebuilt a few gearboxes over the years and each time I have tried to find an oversize circlip 22G851 to no avail. When I have asked different suppliers, they tell me they have never had them. So nobody uses them. This doesn't change the fact that there can be a gap 0.098 to 0.100 at the bearing. I have had this size gap before and used the standard circlip as there is no other. I have always worried about this especially when I put a lot of effort into getting all the other clearances and preloads correct. Previous gear boxes have only been used on standard spec engines and bieing classics not used to cover great milage. I am building another box and this one is going to have to take more power.
Is the extra clearance taken out by the 3rd motion shaft bearing retainer shims?
Can someone tell me why it is not important to fit the oversize circlip?

http://www.leacyclassics.com/22g851.html

If something is worth doing, it's worth doing half of.

Maybe they still have some if advertising them?

If something is worth doing, it's worth doing half of.

I will contact them and see. I ordered one from somerford a couple of years ago having been told by them they definitely had them only to be sent a standard size clip. They didn't seem to know that there was a difference when I complained.

Have you tried looking for a circlip/ snapring from an engineering supplier?

What is the OD of these, I have never measured it, but a quick look at circlips in general, mainly metric ones shows that they are 2.5mm thick from about 65mm OD upwards to about 90mm where they then go to 3.0mm thick. That should be enough to surface grind back to your desired size, all depending on the required OD of course

Why not just cut some shims to match the face of the bearing. That way you can get the clearance perfect...

Edited by TurboDave16V on 17th Oct, 2014.

Considering the wear I have seen on these circlips, I would personally go to the bother of surface grinding one to size. But then thats me

The OD of the circlip is 75.32 mm and the thickness is 2.387 mm 2.465 in and .094 in.
A circlip at 2.5 mm I could definitely work with. As far as I can find out, the thickness of the oversized circlip is .097 in, so I will look again. Thanks for the help.
What I don't understand is why there is so little information about it, and why the gearbox rebuilders or spares suppliers wouldn't have a supply of circlips that size for the mini box. As I mentioned it seems to be ignored

I have just ordered a circlip from bearingbasement.com 74.5mm unsprung £1.07 delivered.

I will let you know how I get on with it.

It is a different part number - the standard one is 22G850.
But I can't see what advantage a thicker clip here will really give other than take up a little slop in the groove. The end float of the 1st motion shaft shouldn't be that critical should it (as long as it not far too tight)?

My bad, I should really look at thumbers first. I suppose it stops the bearing tipping it its bore

Edited by Sprocket on 18th Oct, 2014.

Maybe, but that bearing has plenty of race width and is a good fit.
My guess is that the fact that no one has them, and most haven't heard of them, means they were found to not really be needed.

I would tend to agree but, most are not exactly putting 45lbft of torque through the gearbox any, more. At least at the higher end of output, I would be looking to optimise wherever I could.

There have been plenty of people who have stripped the teeth off the first motion shaft, how many of those had the fit of this circlip by the book? Not saying its why the gear broke, but whats to say its not a contributing factor? The bearing housing is aluminium, and will distort under load. Also, if the fit is not important, why is there always wear on the clip on long mileage standard boxes?.... it is clearly taking some load as the bearing moves.

Same can be said for the snap ring on the fourth motion double roller bearing snap ring and retainer.

Ultimately if you dont want to do anything about the sloppy fit of the circlip in its groove, I have no problem with that. If its something I can easily adjust the fit of, I will, after all that is what blueprinting is all about.

I'm not saying your wrong, far from it, but for the effort of getting it right on a high output motor it has to be worth the piece of mind if nothing else.

Ok I have done it.
With the bearing fitted the gap is .101 in. My original circlip is .094 in. If I reused it there would be a gap of .007 in. Too much.
As far as I can work out the gap after the circlip is fitted should be .002 to .004 in.
My metric circlip is .098 in. Using this circlip the gap left is .003 in. Much better than .007 in
I am happy with that. A good result.
Thanks everyone

I don't understand why I need this. If the bearing spins, you're buggered.

That reads out of context. Care to explain a little better Vegard? :)

Good stuff :)

Colin. Is that CarlS in your avatar?

You're asking the wrong person........

Haha, have you been sniffing the thinners Andy?

It looks like you Carl.