chain keeps falling offf no matter what
- Thread starter lowaus
- Start date
lowaus- Welcome to the forum.
I'm assuming you're talking about your engine chain?
In general, you need to make certain that your wheel gear, and output shaft gear are lined up almost perfectly.
Do you have a rag joint wheel gear? Is it loose/ wobbly?
Do you use a chain tensioner? The wheel has to be in line just like your gears. (You can probably remove the tensioner completely- search that and decide)
Is your chain tension correct? Press up or down on it in the middle, it should only move 1/2' or so. (Be sure to lube your chain with whatever you like best)
Is your rear wheel aligned properly? Is it tight?
That should get you going in the right direction, good luck!
I'm assuming you're talking about your engine chain?
In general, you need to make certain that your wheel gear, and output shaft gear are lined up almost perfectly.
Do you have a rag joint wheel gear? Is it loose/ wobbly?
Do you use a chain tensioner? The wheel has to be in line just like your gears. (You can probably remove the tensioner completely- search that and decide)
Is your chain tension correct? Press up or down on it in the middle, it should only move 1/2' or so. (Be sure to lube your chain with whatever you like best)
Is your rear wheel aligned properly? Is it tight?
That should get you going in the right direction, good luck!
Alignment, alignment, alignment & tension, tension, tension.
As Trey said, the sprockets must be aligned perfectly so the chain runs in a straight line between them. No lateral offset. The tensioner wheel must also align with the chain path. Often the tensioner bracket must be bent or twisted to achieve this.
Lay a straight edge against the sprockets. The edge must lay flush against both sides of the sprockets.
If the rear sprocket wobbles or is not concentric with the hub that too will cause chain derailing problems.
Lots to read here on chain/sprocket alignment. Try the search feature and you'll have plenty to read on the subject.
Tom
As Trey said, the sprockets must be aligned perfectly so the chain runs in a straight line between them. No lateral offset. The tensioner wheel must also align with the chain path. Often the tensioner bracket must be bent or twisted to achieve this.
Lay a straight edge against the sprockets. The edge must lay flush against both sides of the sprockets.
If the rear sprocket wobbles or is not concentric with the hub that too will cause chain derailing problems.
Lots to read here on chain/sprocket alignment. Try the search feature and you'll have plenty to read on the subject.
Tom
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HI,
If the chain line is reasonably good, take a file and bevel the teeth on the rear sprocket.
Hope this helps you.
Andrew
If the chain line is reasonably good, take a file and bevel the teeth on the rear sprocket.
Hope this helps you.
Andrew
Do this and you'll get it right.
However, since you're in Australia, it's actually "tension, tension, tension & alignment, alignment, alignment"........I've been told that things circle backwards down yonder.
Good luck in your 'tweeking'!!
Mark
so ive noticed that my rear sprocket doesnt spin straight. how do i make it so it spins in a straight motion also no i dont use the chain tensioner. and i bought a 415 chain but that makes the bike not move at all. does anyone know the problem with that.
as i installed my rear sprocket,i used a clamp and a wire on the frame.it served as a guage.i had my bike upside down for this process.first i trued the wheel,making sure all the spokes were snug.then installed the rubber mount and sprocket.as i tightened the bolts a little at a time,i keep turning the wheel to make sprocket as straight as possible.
using a rod or wire to help true the sprocket is the only way to do it-unless a person has a dial guage.
with 415 chain,removing the sprocket cover will reveal the issue with it not moving,possibly it is rubbing on part of the aluminum engine case.
using a rod or wire to help true the sprocket is the only way to do it-unless a person has a dial guage.
with 415 chain,removing the sprocket cover will reveal the issue with it not moving,possibly it is rubbing on part of the aluminum engine case.
It really helps to see a picture of your back wheel and motor mount.
Some wheels just suck for trying to get a sprocket attached true while others like many 7-speed wheels with a hub the size of the sprocket center hole. That helps with the vertical alignment which when off causes your chain to get tight then loose then tight again as the sprocket spins but not the horizontal side to side 'wobble' which if more than 1/4" (10mm) will throw chain.
You didn't mention the engine brand either but did you check the sprocket on a flat surface to insure the sprocket itself is even true to start with?
If you have a wobble in your sprocket it will never true up and more common than you might think.
Wobble has to be adjusted as mentioned above by mounting the wheel so you can spin it and tighten bolts to bring things in line.
Just pick a fixed spot behind your line of sight as you slowly spin the wheel to see where it needs to come in as going back out is usually futile and why go in in repeated small steps in and offset pattern like car wheel lug nuts.
As mentioned your engine drive sprocket and rear wheel sprocket need to be in line and true and that starts with your engine.
Looking straight down over your top bar is your engine dead center side-to-side wise and if you hold that top bar with with hand and your cylinder head with the other pushing back and forth as hard as you can does your engine move AT ALL?
If your motor is not solidly anchored to the frame enough to not move by hand it certainly won't stay true throwing 2 or 3 HP at it, it will lean to the left and nothing you do with the back wheel will solve that.
