no chain tensioner

GoldenMotor.com

motorkid

New Member
Jun 24, 2012
2
0
0
porland
after many struggles trying to get the chain tensioner to work i decided to take it of and go with out it. i took out another link and the bike ran good but after about 1/4 of a mile the chain broke, so i fixed it and within 30 seconds of riding it the chain broke again. why is this happening??

:-||
 

bigbutterbean

Active Member
Jan 31, 2011
2,417
3
38
Lebanon, PA
cheap chain, im guessing. shouldnt be an issue iif you get a better chain. I have been running my drive chain without a tensioner for over a year with no trouble.
 

motorkid

New Member
Jun 24, 2012
2
0
0
porland
cheap chain, im guessing. shouldnt be an issue iif you get a better chain. I have been running my drive chain without a tensioner for over a year with no trouble.
yeah i was hoping that could be just the problem, since I am using the cheap #415 chain issued with a china kit. what chain do you use?
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
How's you chain tension and alignment? If they're not right on you'll have chain problems with any chain you use.

The chain must run straight, not pulled off to either side. The rear driven sprocket must be concentric with the hub, no wobbles.
The tension must be from 1/2" to no more that 3/4" of slack. Too tight or too loose, you'll have chain issues.

Tom
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,537
264
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living the dream in southern california
2door's right on the money.

i'd bet your chain isn't lined up correctly, like your motor sprocket sticks out farther than your wheel sprocket (or vice versa.)

when you're riding, the chain catches on the edge of a tooth, and instead of sinking into the groove, tries to ride over the top, which tightens it up till it snaps.

many people run without the chain tensioners (me included. i've never used one. i have a special box for them. it's marked "trash.) but almost every bike needs a lot of messing with to get everything lined up.
 

Mind_Reader7

New Member
May 1, 2010
392
1
0
Northam, Western Australia.
Your sprocket isn't straight.

On my old bike, I never ran one. The frame allowed the back wheel about 1" of play, so even if the chain stretched, I would either move the wheel furhter back, or shorten the chain and move it forward.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
how do you get the peddle side to work, i had trouble getting both chains to be right at the same spot
There are several ways. One is to fabricate a tensioner for the pedal chain. You can use a derailer sprocket or a grooved wheel. Bike shops also sell a conversion kit to change a multi-speed bike into a single speed and in the parts is a spring loaded tensioner that takes the place of the derailer.

I've built a couple of pedal chain tensioners for bikes that are not spring loaded but they are adjustable. One thing to keep in mind if you have coaster brakes is the stress that is applied to the tensioner when you brake (back pedal). It must be strong enough to take that force.

Pedal chain tension isn't as critical as the engine drive chain so you can get away with a pedal chain that is a little loose. However, coaster brakes rely on the chain so you don't want it coming off or derailing. Brakes are sort of important.

Tom
 

bluegoatwoods

Active Member
Jul 29, 2012
1,581
6
38
Central Illinois
The pedal side chain is one good use for these awful kit supplied chain tensioners. Just mount it upside down, with the roller pushing down against the lower chain 'span'.

The only time it has to bear any stress is when braking with the coaster brake. And it can handle that.