How to Solve Chain Stretch

[flashstar]

I am using the 415 chain that came with my Dax 70cc kit. I was planning to not use the tensioner until I realized that the chain was too long to go untensioned but too short to remove another 2 links. I reluctantly put the tensioner on and was surprised by the amount of stretching after 3/4 of a tank. I actually went through the tensioner adjustment completely and had to reposition the tensioner so that I could put more tension on the chain.

Well, after 3/4 of a tank the chain has stretched enough to go without a tensioner. I removed the tensioner entirely and shortened the chain by 2 links and it's still a bit on the long side!

Basically, this chain stretches worse than string cheese on a hot day. Should I look for some high quality 415 chain, 415h chain, or #41 chain? Can I use a 1/2 link? I've heard so many different answers so I'm trying to find the best solution. I don't mind ordering something online.

I'm using the Tophat adapter, so the sprocket is completely true. I don't need the tensioner as a guide.

Thanks

 

[210061741]

1st make sure the engine isn't tipping to the side.
Sometimes they have a tendancy to do that.
Put a L shaped bracket off the backside of the rear clutch cover botlt that is closest to the seatpost and brace it off of the seatpost.

Then cut off some of the rear bracket at the square end where it contacts the motor or use thin shims like .032 inch thick cut to a tee shape to fit between the bracket and the motor and clear the studs. Leave a little hang out so you can grab it with vise grips so you can remove or position the shims.

Get the chain tight but not over tight.
You will trash the 6202 countershaft bearings or wear out your rear hub real fast.

Toss that tensioner in the trash and use the .032 shims.
1 shim will take up close to 1 link worth of slack.

Yes the chain will still stretch but add in another shim and youre good.

 

[Al.Fisherman]

http://motoredbikes.com/showthread.php?t=23285

 

[flashstar]

Thanks for the information. My engine is definitely leaning to the left. The bracket is a good idea, but I don't have any fabricating equipment. Would the right size L bracket from the hardware store work? I'll look at getting some shims. Also, is the 415 stock chain generally good enough?

Thanks.

 

[Al.Fisherman]

Thanks for the information. My engine is definitely leaning to the left. The bracket is a good idea, but I don't have any fabricating equipment. Would the right size L bracket from the hardware store work? I'll look at getting some shims. Also, is the 415 stock chain generally good enough?

Thanks.

Actually my bracket is a modified "L" bracket, store bought that I had laying around. Go get a "L" bracket and put it on temp. Once the bracket is mounted to the case you can rotate it to see where the arm needs to be cut to rest up on the tube. Since the bracket will rotate 360 degrees this is not a problem. The worse case as far as tools is to buy a hacksaw blade and wrap one end with tape or clamp in Vise Grips and cut off what you need to.

 

[motorbikemike45]

On my Staton chain drive bike I replaced the chain with high quality chain from a local industrial supply store. 1/2 links work fine.

 

[AussieSteve]

Well, after 3/4 of a tank the chain has stretched enough to go without a tensioner. I removed the tensioner entirely and shortened the chain by 2 links and it's still a bit on the long side!

Mine didn't stretch that fast. After 5 tanks, not much has changed. Mind you, early on, the tensioner bracket was moving a little, making constant roller adjustment necessary. I had insulation tape under the tensioner bracket - a no-no as I learned.
Just a thought, though, check your rear axle nuts and make sure the wheel isn't pulling forward a little, loosening the chain. (Can't hurt to check)
... Steve

 

[Fabian]

Hi Flashstar

This is how you solve your 415 chain stretch issues - get a decent 415H o-ring chain.

 

[Hajuu]

Yeah I also fell for the wheel slipping a bit and causing loss of tension..

The drive from both sides of the axle really seems to drive the thing out unless its *really* secure.

However with the hanger style axle bracket things on your bike its easy to just slide it evenly back or forward to account for the slack (usually). So I ended up setting my tensioner to max (which also formed the clearest angles as far as frame and tyre to chain was concerned), and then adjusting my wheel quickly with quick release nuts on the back tyre to account for the slack when neccisary.

 

[Hajuu]

Yarr, I keep falling for posting on these old threads!