Rear Chain touches the inner chaincase

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pierodn

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Hi All,
The rear chain turning around the gearbox sprocket touches (with clank clank noise) each around the inner chaincase against the sealing disc.
Contact takes place at the end of anticlok wise just the rear chain ets the sprocket.
The gearbox sprocket seems well thighten, the rear wheel is on axis and also the rear sprocket.
What should I check?
Change the chain?
Ciao.
Piero
 
You might want to check to see if the center chaincase stud is not mis-adjusted which will pull the chaincase in too far at the rear. Jim
 
pierodn said:
Hi All,
The rear chain turning around the gearbox sprocket touches (with clank clank noise) each around the inner chaincase against the sealing disc.
Contact takes place at the end of anticlok wise just the rear chain ets the sprocket.
The gearbox sprocket seems well thighten, the rear wheel is on axis and also the rear sprocket.
What should I check?
Change the chain?
Ciao.
Piero
Click to expand...

What chain are you using?
If its a non standard heavy duty, or o-ring type chain, not only will you incur the wrath of 'Andychain' but it could also be part of the problem you have.
 
comnoz said:
You might want to check to see if the center chaincase stud is not mis-adjusted which will pull the chaincase in too far at the rear. Jim
Click to expand...

Hi Jim,
i agree, but the chaincase stud has the two shims and washer as per manual!
Can I increase the thickness?.
Ciao.
Piero
 
Fast Eddie said:
pierodn said:
What chain are you using?
If its a non standard heavy duty, or o-ring type chain, not only will you incur the wrath of 'Andychain' but it could also be part of the problem you have.
Click to expand...
Click to expand...

Hi,
I mean, but i really dont know.
It seems like the other!
Ciao.
Piero
 
Piero,

is this a new problem?

you have not mentioned this before, did you put a new/different rear chain on recently?
 
pierodn said:
comnoz said:
You might want to check to see if the center chaincase stud is not mis-adjusted which will pull the chaincase in too far at the rear. Jim
Click to expand...

Hi Jim,
i agree, but the chaincase stud has the two shims and washer as per manual!
Can I increase the thickness?.
Ciao.
Piero
Click to expand...

You can increase the thickness as needed. You don't want to put pressure on the chaincase that would cause it to be out of line where it bolts to the engine.
I would remove any washers and bolt the chaincase to the engine alone. Then measure distance to the center mount to see how many washers are needed to hold it in that position. Jim
 
Yes, the inner chain case needs to be shimmed at the center stud so the mating surface at the crankcase sits flush. This will both bring the inner case out a little from the chain and help keep the mating surfaces between the inner and outer true.

If this is not done, the case will flex or warp (ordito) when tightened. This will cause the case to leak oil and possibly interfere with the drive chain.

The bad part is that you need to disassemble the primary and remove the inner to add shims. Practice make perfect.

For what it is worth, I have a VX530 which is very slightly wider than a heavy duty 530 with no interference.
 
1up3down said:
Piero,

is this a new problem?

you have not mentioned this before, did you put a new/different rear chain on recently?
Click to expand...

Recently?
No, the bike was stopped from 20 years!!!!!
 
comnoz said:
pierodn said:
comnoz said:
You might want to check to see if the center chaincase stud is not mis-adjusted which will pull the chaincase in too far at the rear. Jim
Click to expand...

Hi Jim,
i agree, but the chaincase stud has the two shims and washer as per manual!
Can I increase the thickness?.
Ciao.
Piero
Click to expand...

You can increase the thickness as needed. You don't want to put pressure on the chaincase that would cause it to be out of line where it bolts to the engine.
I would remove any washers and bolt the chaincase to the engine alone. Then measure distance to the center mount to see how many washers are needed to hold it in that position. Jim
Click to expand...

Hi Jim,
I mean, i will do it.
Ciao.
Piero
 
pete.v said:
For what it is worth, I have a VX530 which is very slightly wider than a heavy duty 530 with no interference.
Click to expand...

Hi Pete,
thank you.
Sorry, but what is VX530 and 530?
Ciao.
Piero
 
I found that most chain is too fat on a Commando. The original Renold chain had very thin sideplates so there is more clearance. I have had to turn my master link around so the clip is on the inside (wheel side) to fix this problem. I would ask Andy who recommends the IWIS chain (as I recall but check older threads on this one). The new Renold chain is not as good as it used to be.
 
batrider said:
I have had to turn my master link around so the clip is on the inside (wheel side) to fix this problem. I would ask Andy who recommends the IWIS chain (as I recall but check older threads on this one). The new Renold chain is not as good as it used to be.
Click to expand...
+1 On this one

Piero,
Check that thick spacer 0.125" in (imperial) or 3.17 in mm is on the top bolt between the gearbox and the inside plate of the engine/ gearbox rear engine mounting. It would be Item # 34, (030023) part number on Group 5 or 7 depending on the parts manual.

This is a common mistake to leave this shim out from in-between the gearbox and the inner side of the engine mounting plate on a Commando. I mostly see this on the outside where the lollypop adjuster item # 39 (06-2654) when bikes are taken apart and put back together from previous owners rebuild attempts.
Without this shim, you tighten up the upper bolt to hold the gearbox. It pulls the rear engine mounting towards the gearbox when the shim is missing. (It bends it inward). When that happens the inner primary case pulls toward that space where the spacer should have been residing. This tends to mark the inner primary with the chain and in addition to that will pull out the chain case fixing bolts holding the inner primary from the engine output shaft mating face.
It can be an expensive mistake if left out.
Cheers,
Thomas
CNN
 
CanukNortonNut said:
batrider said:
I have had to turn my master link around so the clip is on the inside (wheel side) to fix this problem. I would ask Andy who recommends the IWIS chain (as I recall but check older threads on this one). The new Renold chain is not as good as it used to be.
Click to expand...
+1 On this one

Piero,
Check that thick spacer 0.125" in (imperial) or 3.17 in mm is on the top bolt between the gearbox and the inside plate of the engine/ gearbox rear engine mounting. It would be Item # 34, (030023) part number on Group 5 or 7 depending on the parts manual.

This is a common mistake to leave this shim out from in-between the gearbox and the inner side of the engine mounting plate on a Commando. I mostly see this on the outside where the lollypop adjuster item # 39 (06-2654) when bikes are taken apart and put back together from previous owners rebuild attempts.
Without this shim, you tighten up the upper bolt to hold the gearbox. It pulls the rear engine mounting towards the gearbox when the shim is missing. (It bends it inward). When that happens the inner primary case pulls toward that space where the spacer should have been residing. This tends to mark the inner primary with the chain and in addition to that will pull out the chain case fixing bolts holding the inner primary from the engine output shaft mating face.
It can be an expensive mistake if left out.
Cheers,
Thomas
CNN
Click to expand...

Hi Thomas, thank you for your interesting opinion.
I mean, but the thick spacer is on place like the center stud washer and shim too.
How thick is the chain?
Ciao.
Piero
 
Simples

Check whether you have a Jap chain on or worse bloody O ring.

The original chain was 10B-1 available from all bearing distributors, max width at
connecting link (widest point) is 20.90mm. You will get budget crap but it should stop the
noise.

You could also use an iwis M106SL as a lot more Norton owners are now using which
is available from me or Jane at Sprockets Unlimited at around £40.

Andy

PS I am selling more and more of this for Commandos and it would be good to get
some feedback on the rear, primary and cam chains. I presume no news is good news.

PPS Sorry to upset the O ring fans with my comments ....get over it.
 
Yes, measure chain width and report. Also to add to good responses. Check the thick washer at the gearbox as said, item 34 here http://www.oldbritts.com/1971_g5.html it mounts between the gearbox and the cradle. Also pull off inner chaincase (I know lots of work) and mount inner chaincase without any shims item 9 and 11 here http://www.oldbritts.com/1971_g8.html onto the engine. As was said measure the gap where items 9 and 11 go and make up shims/washers to make up the correct space if not a tiny bit more. Re-assemble and see where the chain to inner primary space is now. It is a very close space from chain to inner chaincase, is normal. Also make sure the triplex chain runs straight and true from engine sprocket to clutch basket while working there.

Sometimes helps to put clip on chain inside, not outside.

Dave
 
Dave, good points but with the right chain the clip can go outside, makes life easier.

Andy
 
Yeah, my clip is on the outside and no problemo. I just thought if it was really tight it may make it work.
 
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