Rear Chain Adjustment

youngjohn

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Non-VOC Member
The Riders Handbook says to adjust the rear chain to 3/4" up and down play - this seems a bit tight. Do people generally abide by this, or go a bit slacker?
Thanks.
 

timetraveller

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VOC Member
3/4" at the tightest point is the important thing. That is when the gearbox main shaft, rear frame pivot and rear wheel spindle are all in line. Any other position and the 3/4" will disappear as soon as the suspension moves and something will either give way or wear prematurely.
 

davidd

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VOC Member
Timetraveller is spot on. I am not advocating this, but I tend to run mine on the loose side. I found that when I adjusted it per the book it would soon be slightly looser. If I kept adjusting it, it would stretch the chain and wear out prematurely. I would follow Timetraveller's advice and see how things wear and adjust accordingly.

David
 

A_HRD

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VOC Member
I take a different approach on my Thornton-equipped Rapide. I use about 1.5 inches of slack. I find that with anything less, I can 'feel' a slight notchy pulling or jerking in the transmission on bumpy bends - that'll be the chain going tight for a few milliseconds under certain conditions. Also, if I use 3/4 inch slack I get through sprockets & chains much quicker and the rear hub bearing (on the chain side) gets loose in the housing. It just isn't worth the money or the hassle; so my advice is - err on the loose side.

Peter B
Bristol, UK.
 

stumpy lord

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Non-VOC Member
HI,
It all depends on which stand you use , rear or centre. For a d type stand 1.5 inches is correct, but it does say after adjusting to put the machine on to its wheels, and check that it has no less than 3/4 slack at its tightest point. When using the rear stand 3/4 is correct.
for detailes see Paul richardsons book vincent page183.
Personaly if using modern o ring chain i would tend to give them a bit more.
stumpy lord.




p
 

mercurycrest

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VOC Member
On a D, I'd keep it as loose as possible without hitting the RFM. I learned this the hard way by breaking a rear hub 500 miles from home. Of course the earlier, inferior, B's and C's don't have enough suspension to have this problem.:cool:
Cheers, John
 

timetraveller

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VOC Member
Come along chaps!! Who has not been carefully reading what I wrote? 3/4" (or more) at the tightest point. See above. Even on the rear stand it will depend if you have standard springs or Pettiford as to what angle the rear triangle is dangling at. Any centre stand, 'D' or Dave Hills type, will also mean that when on the stand the rear end is dangling well below the 'everything in a straight line position'. Gentlemen, ask yourselves "Is your rear end dangling?" If it is then take the appropriate action.
 
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ET43

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Non-VOC Member
My appropriate action was to fit a roller chain tensioner. Worked for me on the Red Thruster, and no doubt will on the trike if I ever get an electric starter! ET43
 
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