Final drive, front sprocket play on spline

Step two:
Quicker than I thought- I've been everywhere before, except the actual engine mounts, one of which was loose and needs new bolts...
Apart from that, and having to lower the bench to suit the bespoke engine hoist, piece of piss 👍

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There is a Loctite product designed to take up gaps when bearings are loose in their housing. You probably need it really clean and a primer and the sprocket hard against its driven direction and a day or 2 for full curing.
 
There is a Loctite product designed to take up gaps when bearings are loose in their housing. You probably need it really clean and a primer and the sprocket hard against its driven direction and a day or 2 for full curing.
Won't work on really shagged splines Vince. And you're forgetting changing down, this puts tremendous pressure on the opposite sides of the splines. The Loctite may take up gaps of up to 0.2mm reliably, but will yield under pressure. Not exactly what is needed.

If only a small gap needs to attended to, strips of feeler guage steel can be used to shim the splines.

The Loctite product is meant for components that have lost their interferance fit, like wheel or crank bearings, gaps of less than 0.1mm.

piet
 
Yeah, I looked at all the info on 660 - evben though it's not deigned for torque through a spline I used it when I fitted my sprocket. No play but it went on too easily for my liking.
 
The new gear and sprocket from Wolfgang fit together nicely cold, certainly not tight. I was wondering about loctite but as said it's not really the right use. Moly paste on the other hand, seems to be the best stuff and used particularly on drive splines and driveshafts.
I'd be really interested to hear any opinions 👍
 
Over the years, since '76, I've fitted quite a few new drive sprockets. The first one that was a tight fit finished up like this:

5th Gear Output Shaft Problem 2.jpg5th Gear Output Shaft Problem 1.jpg5th Gear Output Shaft Problem 4.jpg

Whether it overwhelmed the case hardening, I don't know, but I never had a problem with the previous ones, which I could push on with my fingers, never did this.
 
You can't really do anything to improve the shaft splines, but i'd at least do a crude check on the sprocket hardness.
Just trying a dot punch will tell you if it's particularly hard or visibly soft.
If you want to tighten the fit, a ring of weld around the sprocket - far enough out from the shaft to not affect the retainer and far enough in to miss the chain - will shrink the center hole slightly as it cools.
If the sprocket tests as soft, heat to cherry red and quench in oil.
 
Hey Andy its easier to remove and refit the RGS engine from the LHS.
Cheers Maurice, yes I found a few posts from you and Red etc that pointed left. All advice is welcome and I try to follow it as best I can 👍. I was just sort of experimenting with my hoist rig and went further than I expected. It came out easily, maybe because I had already removed the alternator and primary? Now that I'm 'experienced' 🤣 I might fully assemble it on the bench and then I'll definitely go left.
 
You can't really do anything to improve the shaft splines, but i'd at least do a crude check on the sprocket hardness.
Just trying a dot punch will tell you if it's particularly hard or visibly soft.
If you want to tighten the fit, a ring of weld around the sprocket - far enough out from the shaft to not affect the retainer and far enough in to miss the chain - will shrink the center hole slightly as it cools.
If the sprocket tests as soft, heat to cherry red and quench in oil.
Sorry, short delay while I picked up a different set of tools and fixed the shed lights...
Well, both the new and old sprockets passed the punch test.
Using weld to tighten the fit is something I'd never have thought of. I can discern veeery slight movement of the new sprocket when trial fitted with retainer, so it would be nice to improve it a bit. It'll take some pretty precise work to avoid the retainer and chain but I know a guy, arc, mig or tig? Both sides? Following welding, would I need to reharden?
 
MIG or TIG, doesn't matter. Both sides would avoid distortion. No, won't need to reharden.
If it's easier two runs of weld on the retainer side and a full circle on the back would work.

It's possible this may tighten it to the point where shrinking it on becomes necessary
 
If looking to repair the splines on a worn out gear, I would check with companies that repair the splines on BMW bikes. The air head bikes from 1970 to 1995, all had problems with the rear wheel splines. The early K bikes had spline problems with the drive shaft.

I had the splines repaired on a 1978 BMW R100RS that were almost completely gone and they welded it with hard facing and it never wore ever again even after 100,000 miles.
 
If looking to repair the splines on a worn out gear, I would check with companies that repair the splines on BMW bikes. The air head bikes from 1970 to 1995, all had problems with the rear wheel splines. The early K bikes had spline problems with the drive shaft.

I had the splines repaired on a 1978 BMW R100RS that were almost completely gone and they welded it with hard facing and it never wore ever again even after 100,000 miles.
More good advice, possibly difficult to find a specialist here in NZ, the last one I knew lost the fight a few years ago, but I take your point.
Possibly interesting, my old 1000 goldwing did a crosspiece on the driveshaft at about 100k, splines were perfect. Different machines wear out in different ways.
 
There is a thread on BMW driveshaft repairs on Adventure Rider, the list of people doing it commercially even worldwide isn't very long.
 
You can't really do anything to improve the shaft splines, but i'd at least do a crude check on the sprocket hardness.
Just trying a dot punch will tell you if it's particularly hard or visibly soft.
Highly unlikely the sprocket would be soft, Greg. It's the splines that seem to get hammered. No easy fix on them without a case split and some specialised engineering work.
 
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