4 Speed Chain drive sproket question

[aaandht]

Chain has been doing the extremely tight to extremely loose crap again, even after a new chain was put on about 2k miles ago. Pulled the sprocket cover off and found that when i loosened the nut for the sprocket I have a bit of play on the sprocket and shaft. Is this normal? Or should I look into getting a new sprocket?

Also I noticed my rear tire is a bit out of alignment(spoke tires), could this cause an issue with the chain?

Thanks

[DogBunny]

If the sprocket teeth are pointed or hook shaped, you need a new sprocket. Try to find on-line pics or drawings of worn sprocket teeth.
I don't know how much play is a "bit."
Sprockets are pretty darn cheep. Buy one, and see if the play goes away.
You mean the chain has tight and loose spots? I don't see how alignment could cause that.

[aaandht]

I should have been more specific. The teeth are fine however the inner spline teeth "seem" worn and have a good bit of play. The output shaft looks fine to me, though.

[williamv1203]

When I got my 88, the front sprocket was loose and the inner teeth were worn to almost flat except for about 1/16" on the outer edge. I never noticed if it caused chain stretch, I just replaced the sprocket and all was well and good.

If you mean loose and tight places as you roll the chain around (with the wheel off the ground) as if you are checking it, this is a sign of chain stretch. This happens and is what they do. If there is excessive loose and tight difference, try to get the loosest section to sit over the very rear of the rear sprocket. See if the chain can be pulled away from the sprocket and how much of the sprocket teeth are exposed. If you can see the furrows of the sprocket below the chain, I would say it needs replaced. If you continue to run an over stretched chain, you will maybe notice a kind of jerky ride at low speeds ~25mph.

Either way, I would replace the front sprocket and the chain. Get a high quality heavy-duty chain. It may cost a bit more but will last longer... If adjusted properly and maintained.

[aaandht]

Originally Posted by williamv1203

Either way, I would replace the front sprocket and the chain. Get a high quality heavy-duty chain. It may cost a bit more but will last longer... If adjusted properly and maintained.

Thanks for the replay. I'm going to be ordering a new front sprocket in a week or so. But the chain is a brand new Diamond 530 chain with 2k miles on it.
There is a pull at low speeds, and when in see the front sprocket move I notice it sort of pull into the teeth more toward the front(if that makes sense). Also I hear sort of a klank as the chain moves to a certain point. I've got to spend some more time on this later this week when classes are over.


The reason why I also brought up the wheel alingment is because I hear the rear disc drag at one point then its silent again. I figured if the rotor is out of whack the sprocket could be also.

[williamv1203]

The noise you hear from the disc doesn't necessarily mean that it is bad or warped.
Raise the rear wheel with the axle nut loosened off, but not fully loose.
With it in neutral, spin the wheel until you hear the disc rubbing and making the noise. Try to center the disc between the caliper where the noise is most prominent. Then tighten or loosen the axle adjusters 1/4 turn at a time while spinning the wheel until the dragging noise either goes away or is consistent throughout wheel rotation. You can use a pencil to lay on the swing arm to where it is against the wheel surface, not the tire, hold it firmly and spin the wheel and feel for pressure on the pencil as the tire rotates. This will tell you if the tire is running true and straight.

Hope that ^ makes sense...

If the sprocket can't be tightened where it is solid on the shaft, the clank you hear may be the loose and tight areas in the chain putting tension on it and causing it to flop around. Yep, it NEEDS to be replaced either way.

If the chain is new as you say, that doesn't mean that it couldn't be stretched beyond good serviceable use. If there is an extremely noticeable loose and tight area, it will give an unproportioned delivery of torque to the rear wheel and the ride will feel unsteady under power.

[DogBunny]

How often do you oil your chain? Running it without oil will greatly decrease the life of a chain. Oil it often and after every time you wash or ride the bike in the rain.

If you have been running a dry chain the clank could be a "tight link" -- that's a link or links which no longer pivot/rotate.

[aaandht]

Lube it every 300-600 miles, depending on rain and such.

As far as the wheel being untrue, I can see the treads actually move slightly when turning the wheel, so it defiantly is out of trueness(is that a word?). As I turn it the brake sounds like it drags as the treads move off center.


I'll definitely try the pencil idea later this week and report my findings.

Thanks!

[williamv1203]

Originally Posted by aaandht

Lube it every 300-600 miles, depending on rain and such.

As far as the wheel being untrue, I can see the treads actually move slightly when turning the wheel, so it defiantly is out of trueness(is that a word?). As I turn it the brake sounds like it drags as the treads move off center.


I'll definitely try the pencil idea later this week and report my findings.

Thanks!

If you have a cast wheel on it'll make it easy to see where it is out of true as the pencil will leave gaps or a darker line around the wheel. If a spoke chrome wheel, it'll be hard to see the line, so you'll have to go be feeling the pressure. Also, if it's a spoke wheel, it may be that the spokes are off a bit. A trueing stand may be needed then.

[billy bob]

Once you have the rear wheel properly aligned, the clanking or binding of the chain should stop. Remember to adjust the chain on the tight spot. I also doubt the chain being worn out with only 2k miles on it. I read that a 530 chain (new) should measure
12.5" pin to pin between 20 links. They say to replace it when the same measurement
exceeds 2.5% or 12.88". Or a worn chain can be determined if you can lift (or pull)
the chain off of the rear sprocket by more than 1/2 the height of a tooth.

Jireh Cycles has tranny sprockets for $19.95, USA MADE, 21 tooth 94-316, 22 tooth 94-317, and 23 tooth 94-318.