Timbone
Well-Known Member
I have put several hundred miles on my bike and I have been obsessing with a simple and cheap replacement for the stock tensioner. I am getting close.
After several failed attempts with springs, I gave up on them altogether. I just observed the tensioner to see what works best and what doesn't work. You don't need a spring!
The chain just wants to roll smoothly onto the rear sprocket. That's want it wants to do - so let it! You don't need a little cog. Almost anything will do. The stock tensioner is made of hard plastic for a reason.
The stock metal piece that holds the roller is plenty strong. Here is what I did to replace the roller:
For the axle, I chose a 5/16 clevis pin, 2" long.
Drop a 1" washer (5/16" hole or close) over the clevis pin. Then drop a 2" fender (5/16" hole or close) washer onto the clevis. This is the inside chain guide.
I made a roller surface out of nylon washers. Couldn't find the perfect size, so I took a 1" washer (3/8" hole and 3/8"deep)and added 3 slim washers (2 on one side, one on another) and superglued then together. This is roughly the same size as the stock tensioner.
Add another 2" fender washer to serve as the outside guide. That's all the roller is!
Run it through the metal holder, add a washer or washers for a snug fit and secure with a cotter pin.
There should be just a touch of play. I am getting good tension with little resistance. The chain is just clipping right over the hard nylon washers.
Take the time to work seriously on chain alignment. Let the chain run over the middle of the roller surface. The chain will contact the metal roller glides (2" fender washers) but that will not affect a good 415 chain.
My first tests were great success! Several miles with a 30 mph run! Pulling the clutch and killing the engine allows a super smooth coast!
Tomorrow, we test with a 12 mile commute to work. Then back!
=Timbone=
After several failed attempts with springs, I gave up on them altogether. I just observed the tensioner to see what works best and what doesn't work. You don't need a spring!
The chain just wants to roll smoothly onto the rear sprocket. That's want it wants to do - so let it! You don't need a little cog. Almost anything will do. The stock tensioner is made of hard plastic for a reason.
The stock metal piece that holds the roller is plenty strong. Here is what I did to replace the roller:
For the axle, I chose a 5/16 clevis pin, 2" long.
Drop a 1" washer (5/16" hole or close) over the clevis pin. Then drop a 2" fender (5/16" hole or close) washer onto the clevis. This is the inside chain guide.
I made a roller surface out of nylon washers. Couldn't find the perfect size, so I took a 1" washer (3/8" hole and 3/8"deep)and added 3 slim washers (2 on one side, one on another) and superglued then together. This is roughly the same size as the stock tensioner.
Add another 2" fender washer to serve as the outside guide. That's all the roller is!
Run it through the metal holder, add a washer or washers for a snug fit and secure with a cotter pin.
There should be just a touch of play. I am getting good tension with little resistance. The chain is just clipping right over the hard nylon washers.
Take the time to work seriously on chain alignment. Let the chain run over the middle of the roller surface. The chain will contact the metal roller glides (2" fender washers) but that will not affect a good 415 chain.
My first tests were great success! Several miles with a 30 mph run! Pulling the clutch and killing the engine allows a super smooth coast!
Tomorrow, we test with a 12 mile commute to work. Then back!
=Timbone=