Tight chain
- Thread starter ben_vayner
- Start date
The chain will stretch and wear the sprocket, the clutch bearing will wear ..
A little loose is good ... 1/2" to an 1" is good ...
If you have a swing arm keep in mind how tight it the chain will be when its at it's furthest point in its swing from the clutch, it needs to still be half to an inch of chain play.
A little loose is good ... 1/2" to an 1" is good ...
If you have a swing arm keep in mind how tight it the chain will be when its at it's furthest point in its swing from the clutch, it needs to still be half to an inch of chain play.
It certainly will ruin a clutch, sprockets, and the chain itself. 1/2" of play is a pretty good rule of thumb. If mine gets more than 3/4" or less than 1/2" I usually think about adjusting. Lube it about once every 10-20 days. Clean it about 60 if primarily on pavement. 10-20 days on dirt. Every ride in sand. That same rule of thumb applies to just about anything that has a chain drive. At least, that's how I ride. Never broke a chain, sprockets, or clutch.
I've heard the swingarm theory before. I can't really say I believe it though. First, An axle to crank distance is fixed. A swingarm doesn't shorten or get longer, nor does it bend. It pivots on a fixed point. Plus, how would you even account for that travel when adjusting the chain. Are you gonna put a 300 pound weight on the seat as you measure/tighten/measure/etc. ? Honestly, I think it's a myth anyways...
Really?!? Kinda new to this mechanical stuff huh?
Swingarm "Theory"?
Sit down and think about it real hard ...
A swing arm has a pivot point between the clutch and the rear axle.
Now to exaggerate take the swing arm and swing it perpendicular to the motor mount, (a flat positioned motor, not a canted forward Rupp).
Put a chain on the bike and move the swing arm back to parallel with the motor mount ... you will not have enough chain to do it.
Weather the swing arm is 1" or 5" or more off parallel to the motor mount you will need to adjust your chain when the swing arm is parallel to the motor mount.
How would you do it? Take the shocks off would be one way.
Maybe a tensioner would be called for.
Trust me, If I'm feeding you a line I will be QUICKLY called out by the respected members of this forum.
Swingarm "Theory"?
Sit down and think about it real hard ...
A swing arm has a pivot point between the clutch and the rear axle.
Now to exaggerate take the swing arm and swing it perpendicular to the motor mount, (a flat positioned motor, not a canted forward Rupp).
Put a chain on the bike and move the swing arm back to parallel with the motor mount ... you will not have enough chain to do it.
Weather the swing arm is 1" or 5" or more off parallel to the motor mount you will need to adjust your chain when the swing arm is parallel to the motor mount.
How would you do it? Take the shocks off would be one way.
Maybe a tensioner would be called for.
Trust me, If I'm feeding you a line I will be QUICKLY called out by the respected members of this forum.
Last edited:
Okay, I think I get it now. I actually made a model to help me understand it better. When crank, swingarm pivot and axle are in a straight line it's at it's greatest length. If the swingarm were perpendicular, it would actually be shorter and looser. A mini bike will definitely not have a long enough swingarm or travel to effect tension by more than a few millimeters. Most of their swingarms are already parallel with the motor mount too. I guess I just thought it was a myth because I never broke anything and never bothered to set tension with suspension travel in mind. It really doesn't effect much unless you ride a dirt bike with lots of travel and a swingarm that's already extended far beyond parallel. Most modern dirtbikes seem to offset it by designing the crank closer to swingarm pivot. Taking off shocks to set chain tension? Not until I start riding a hill climber