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Miss November XS2 tribute
- Thread starter Raymond
- Start date
I have a feeling that the previous owner experienced this same problem, and tried to solve it by installing a longer camchain. So, essentially you're chasing his original problem.
Let's try to break this down to 3 possible areas to check.
1. Vertical center-to-center dimension of the crank and camshaft is close to 24". Unfortunately I don't have the precise value. Some things that can affect this spacing are:
- Crank bearings not properly seated on their pins
- Case/cylinder/head alignment dowels not fully seating.
- Too thick gaskets.
2. Front guide positioned too far rearward.
- Bad guide bar nuts.
3. Rear slipper positioned too far forward.
- Remove rear tensioner.
Let's try to break this down to 3 possible areas to check.
1. Vertical center-to-center dimension of the crank and camshaft is close to 24". Unfortunately I don't have the precise value. Some things that can affect this spacing are:
- Crank bearings not properly seated on their pins
- Case/cylinder/head alignment dowels not fully seating.
- Too thick gaskets.
2. Front guide positioned too far rearward.
- Bad guide bar nuts.
3. Rear slipper positioned too far forward.
- Remove rear tensioner.
Agreed Steve - but if the crank bearing weren’t seated - how could the lower engine cases be bolted together?
On your other points, here are a couple of suggestions (which may be way off base...):
On your other points, here are a couple of suggestions (which may be way off base...):
- Remove the rear tensioner entirely and Then connect the timing chain;
- Remove the front timing chain guide...but that make make it impossible to ensure that the cam chain timing is correct - so maybe not a good idea....?
Pete, spit-ball away. I purposely threw that up here as an outline for thought. I'm spit-balling too...
When I had similar problems with the cam chain, on two separate ocassions, it was due to the following:
- Exactly as Jim pointed out. When I pulled hard on the chain the kink popped out and the crank was then free to rotate when pulling the chain back and forward.
- As TM points out the tensioner rear guide was to far forward and actually jammed in the central gallery. This required me to lift the cylinders about 1 cm to free it, so check that with the tension bolt released the rear guide is nice and free. Just stick your finger down the central gallery and push the rear guide back as you lower the cylinders.
Thank you All for your suggestions. Jim, when I read the above I thought 'Aha! That looks like the answer.'
Wish it could have been. Today, head part-torqued down with sockets over studs, replaced the camshaft with all four bearings, hooked a long piece of wire through both ends of the chain, and followed the procedure. Rotated the crank 1/2 turn forwards and backwards with wire held up, under slight tension to remove any kinks.
Then, crank to TDC, camshaft placed correctly, chain fitted at front. Pulled rear end of chain with a small screwdriver through a pin, with leather gloves on for full purchase, standing on a stool to get optimum body position, Ever Willing Assistant - for how much longer? - preventing crank from turning with socket & tommy bar. Pulling as hard as possible then using free hand to push the camchain onto the teeth at rear of sprocket, the best chain position I can achieve is still one tooth short:
For me just now that looks like defeat. Been over & over this in what passes for my mind. Chain is correct length of 106 links including rivet link not shown in photo. Cam sprocket is correct at 36 teeth.Crank sprocket must be the correct 18 teeth or the motor would have self-destructed long ago.
Thinking of buying a new chain for two not very good reasons.
Firstly, could measure the new chain's length, run it through to replace the present chain and measure the length of that. But if anything, the 'used' chain in the bike should be longer. Surely, all DID 219 chains must start out the same length until they stretch?
Secondly, a chance to check that the present chain really is 106 links. I must be going mad . . .
Since boredom has jumped on me this afternoon I decided to count links on DID 219 cam chains and got the following:
- Endless cam chain has 53 outer plates
- Split cam chain has 52 outer plates plus one link
Raymond
How close to getting it on do you think it is?
How close to getting it on do you think it is?
When I did mine I could not pull it on by hand. That's why I used the T-Handle Allen wrench as a lever.
Just hook the old chain to the new and pull the new one back out. If it measures less than 106 links, there ya go. If it is 106 links, feed it back in and with the cam removed, have a good look at what's going on in the chain tunnel.
OK Raymond... just for reference, I measured the chain I took out of my SG. When I replaced it, I compared it to the new and it was exactly 1/2 link longer.
So, here's the old... stretched out it's 32.5" and I count 106 rollers. If my new is any indication, yours should be about 3/16" shorter (half link).
So, here's the old... stretched out it's 32.5" and I count 106 rollers. If my new is any indication, yours should be about 3/16" shorter (half link).
OK... forgot he just shortened the original. You can still pull the original out by attaching some safety wire to the end and pull the safety wire through. It's kind of a bugger to do that way... but it can be done.
At this point I think I'd want the chain out for some counting and measuring....
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Maybe if @Paul Sutton still has his old chain laying around, he can measure so's we can compare to my old... get a better overall picture of what we should be seeing?
And, a fork in the road.
This issue just has to be something fundamental.
There have been several "too short" postings in here, mostly solved by compressing the head with spacers, but some others caused by the front guide.
MaxPete and Robinc did some extensive measurements and analysis on the front guide, and its variants. May be worthwhile to compare your guide fitment measurements to theirs.
Starting around post #124, but the entire thread is informative.
http://www.xs650.com/threads/lucille-pulls-another-one-on-me.52694/page-7#post-559905
This issue just has to be something fundamental.
There have been several "too short" postings in here, mostly solved by compressing the head with spacers, but some others caused by the front guide.
MaxPete and Robinc did some extensive measurements and analysis on the front guide, and its variants. May be worthwhile to compare your guide fitment measurements to theirs.
Starting around post #124, but the entire thread is informative.
http://www.xs650.com/threads/lucille-pulls-another-one-on-me.52694/page-7#post-559905
Unfortunately I do not have the old chain now but it only had 11000 miles on it and from memory was not noticeably stretched. Like Jim, I threaded my new chain on by wiring it to the old chain. But word of warning, when threading the chain on make sure you keep tension on both ends of the chain or it will kink and possibly jam the crank. Mine jammed and it took a bit of effort to unjam it. When fitting the link I had to use a small slotted screw driver to lever the ends together by pressing the blade between a tooth and a chain link.
I guess the big question is "How long is the chain?"
I guess the big question is "How long is the chain?"
Could be the answer. I do know I have never been strong enough the stretch a metal chain without a mechanical advantage.
Well, it’s very early on Sunday morning for Raymond right now so we should have some more data in a few hours.
Pete
Pete
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