Hi All

My sons bike had a terrible sound - so we looked inside and discovered the tensioner was 23mm out only a miracle  it had not dropped out !!

I considered a US mod like u guys do it - or a German mod. - However the chain seemed extremely loose.

So I started reading the guides on this site and youtubing ect - I have never had a bike opened up like that before.

But first time you do this It is really time consuming , we had both the Clymer and the workshopmanual and still there are small things not described.

Anyway - I was blown away over how much difference the NEW guide/tensioner (12811-24B00) made.

The old one (30.000 miles) was cracked and had lost its original shape - the new one will tension the chain almost 3-5 millimeter more in all its length.

Our old chain was actually just within specs.

But after mounting the new chainguide and new camchain -
the chain-tensioner went from 23mm to 8mm ..

So just a tip maybe try changing this chain guide and put in your old tensioner and see - before opening the headcover and changing the camchain - its a 5 min job vs hours  :-D

As you can see on the photo the old "guide" is on top and have both ends aligned with a bolt.

The front guide is that easy to change?

I think that's the rear guide too, he shows the top pivot point, but the bottom has a radius to it and is attached to the chain tensioner.  Notice the cracks in the plastic? 1 owner said the plastic came off and clogged his oil pump pickup.  While that's an extreme, don't discount it.

The front guide is the flat one and can only be accessed by removing the head.

Yes, the rear guide can wear.  But it's only a 5 minute job if you've already have the clutch and primary gear off.  And sometimes the castings of the head and cylinder are mismatched making it difficult to get the guide out or back in.  And it will take shear determination to get the pivot bolt back in.

As far as the old guide flattening vs. the new guide... no matter what you do, you still have a guide that's x long.  The only real change is where the radius at the end is, that may affect the angle of the tensioner and cause it to be extended further, but I think the wear in the plastic guide will have a larger effect.  

Replacing the rear guide will change the tensioner extension, but going from 23mm to 8 is probably due to an extreme amount of tension in the chain vs. the minimal amount due to installation.  Thermal growth/ contraction puts an extreme amount of tension in the chain that's very difficult to duplicate by prying into place.

You'll need to check again after awhile.

04Savage04 wrote on 05/05/24 at 07:28:17:

The front guide is that easy to change?

Sorry my mistake it was the "banana guide" we changed the other one looked fine with no wear or crack ect   :-D

Surviving Philly wrote on 05/05/24 at 10:15:31:

I'd have to say no, but it can be both.  The rear guide can wear/deform and is replaceable.
You'll have to inspect it and decide for yourself.

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This a hard question as what will the next issue be?
I don't think the verslavy tensioner will allow the chain to stretch enough for the chain to start rubbing against itself.  The pin should hit the slot by then and I don't know how long it'll go after that.

My personal preference would be to double the mileage when you 1st replaced the stock tensioner and replace the chain at that point.  Assuming that ride length hasn't changed.

The only other issue is chain wear (not stretch).  Sooner or later links will bind or not rotate properly and you should replace regardless of stretch.

04Savage04 wrote on 05/05/24 at 11:43:20:


Let me be clear... pulling the guide straight down ain't gonna happen unless...
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