My chain is going to rub on the tire just a hair and it will align better if I space the engine sprocket not the wheel sprocket. What is a good technique for spacing? Any special tools needed (i.e. gear puller etc...). What material should I use for spacer..metal, nylon etc..? It appears to be an appropriate fix because the installation guide says quote, "Sprocket on 66cc my need spaced outward to clear 415 chain", end quote.
How to space engine sprocket
- Thread starter jnnova
- Start date
I had to put a spacer behind for my #41 chain, glad I did, it's a nice chain!
I used a lock washer (circular piece of metal, snipped and bent)
First I bent it back to be flat (vice, vice grips).
Then you have to cut the slot in it to be bigger (dremel disc) so that it fits around the woodruff key.
It has to be ground down on the inside (file/dremel) to fit around the stuff that holds the sprocket on.
It also has to be filed around the outside (grinder,file/dremel). It can't be any bigger than the sprocket, or it will grip stuff it's not supposed to!
Then you put the sprocket back on overtop of it. You porbably do need a sprocket puller, but each kit should come with one. You also lose a lot of threading for the sprocket when you do this, so I had to use red loctite to make sure that sprock stays on.
I used a lock washer (circular piece of metal, snipped and bent)
First I bent it back to be flat (vice, vice grips).
Then you have to cut the slot in it to be bigger (dremel disc) so that it fits around the woodruff key.
It has to be ground down on the inside (file/dremel) to fit around the stuff that holds the sprocket on.
It also has to be filed around the outside (grinder,file/dremel). It can't be any bigger than the sprocket, or it will grip stuff it's not supposed to!
Then you put the sprocket back on overtop of it. You porbably do need a sprocket puller, but each kit should come with one. You also lose a lot of threading for the sprocket when you do this, so I had to use red loctite to make sure that sprock stays on.
You can accomplish this by moving the shaft out a bit. Remove the clutch cover and pressure plate (right side of motor), screw in the clutch puller tool, and whack it a couple of times with a mallet. This is discussed in more detail in another thread in the forum. This is what I did to keep my 415 chain from contacting the engine block.
make sure thw wheel sprocket is concave side out
i always reccomend changing the tire size to 195 when this is a problem
whanging on the clutch shaft to move it will probbly change the front to rear sprocket allignment (then chain comes off....lol) and may damage front sprocket seal or unseat bearings
i have seen this happen
all advice is free and may be disregarded
stay dry
gubba
i always reccomend changing the tire size to 195 when this is a problem
whanging on the clutch shaft to move it will probbly change the front to rear sprocket allignment (then chain comes off....lol) and may damage front sprocket seal or unseat bearings
i have seen this happen
all advice is free and may be disregarded
stay dry
gubba
I think that I'm going to use brass washers...plus I might drill holes in the sprocket and shaft then do what they do with aircraft and safety wire the sprocket so that it can turn off the shaft.
That is what we're trying to do here, move the front sprocket out a bit. Some more discussion in this thread http://motorbicycling.com/f40/chain-rubbing-case-front-sprocket-30930.html.
Adding washers behind it won't work; all you'll do is push the center of the bearing into the engine & cause it to bind when you tighten the main sprocket nut!
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I can't say exactly what the maximum would be, I was able to get what I needed which was about 2mm. Venice Motor Bikes can probably provide a better answer for you--I learned about this technique from him (thanks VMB!).
Aha!
So the shim washers will NOT work! ...
I'm a hack... if I had an alignment difference that small I'd probably twinkle the stays a bit... or whomp on the seat post and give it a wowie to move things over. Definitely got some big hammers here, and blocks of wood.
even sheldon brown speaks of tweaking a frame...
rc
So the shim washers will NOT work! ...
I'm a hack... if I had an alignment difference that small I'd probably twinkle the stays a bit... or whomp on the seat post and give it a wowie to move things over. Definitely got some big hammers here, and blocks of wood.
even sheldon brown speaks of tweaking a frame...
rc
You should only consider moving the whole shaft over if the chain is hitting the engine case, not to get extra chain to tire clearance!
It just occurred to me that you must only get a fraction of movement moving the shaft because if you moved it too far the clutch swing arm cam shaft thing (don't know the name exactly) wouldn't work anymore. I think I need more movement then that. Tell you what going to take some pics in a few hours so that we all can see...looks good anyway, want to show it off.
Just read this comment.....my problem is chain tire clearance not the case. I'm going to take a good look at this and take some pics and find a solution and let you guys know...so far you guys have been very helpful and I want VMB to see he seems knowledgeable.
