Popping chain noise

george_n_texas

george_n_texas

Member
I figured out the warp in my rear sprocket it was the outer rag joint. I took that out and it is flat but I may hafe inverted the chain do you think this would make it start makin poppin sound like when you back up? I have the thicker 410 chain N sprockets. I haven't taken it for a spin yet just short distance.

I also noticed the bearing is missing in the clutch as well as the washer under the barrel in the carb. My spark plug looks good so I guess the needle pretty much stays in place with gravity.
 
If the chain is popping the sprockets aren't lined up good enough.
I wouldn't ride it much like that cause soon as it stretches or the motor shifts it will jump off the sprockets and jam something.
Chainline is prolly the most important part of the setup and install.
Get it perfect
 
chains work both ways, you can't invert it. (unless you have an early 1900's block chain, which you don't.);)
 
George,
What the heck do you mean when you say, "The bearing is missing in the clutch" and "the washer under the barrel of the carb? Help us out here.
Tom
 
There's supposed to be a bearing at the end of the small rod the actuator arm presses in on isn't there? I think it fell out when I first assembled the bike and never found it. I wasn't sure but then I saw someone posted about a washer with a small slot to match the barrel to hold the needle down I can't remember seeing one.
 
George,the the actuator lever turns a rod that has a flat side. The flat side is towards the clutch/drive shaft when engaged, and pressure is released on the clutch shaft allowing the clutch spring to shove the clutch disc against the clutch plate and off you ride. When you pull the clutch handle, the actuator turns the rod so the flat side turns away and the larger diameter/radius of the round part pushes against the clutch/drive shaft, separates the clutch plates, and stops sending power to the chain sproket. I don't recall any bearing. There is a groove machined around th rod part way up, and a little pin in a hole in the cover engages the rod and holds it in place. This is a pretty Rube Goldberg design, and if the little pin falls out, the rod slips up and stops working. But all this is no issue with chain popping. 2100... is right, the popping is the chain under lateral (side) stress popping off the tips of the sprocket teeth because the sproket is not parallel with the chain..that's not a good sign!
 
While it's true that a "popping" chain is a sign of misaligned sprockets, if it happens only once in a while and/or your sprockets are aligned - I've found the stock rear sprocket's teeth are sometimes not beveled or beveled only on one side.

Whippin' out the trusty Dremel and beveling the teeth can help a lot - don't actually "sharpen" them though as you'll weaken the teeth/increase wear - leave about 1/16" flat on the tips.

However it IS critical to line up the sprockets perfectly, beveling the teeth is just a "finishing touch" ;)
 
Well I rode the thing to Wal-Mart N back NP pops intermittantly. Noticed the chain looked real loose when I got there and when I got back seemed tight again...commin back entails letting engine brake a bit as it is a big hill. Anyhow this is my test bike the peugeot is gonna be my ride eventually just need a few parts. The chain looks very straight and aligned. The poppin might be from the main shaft nut you turn to thread the chain over the motor sprocket came loose and I misplaced the spark plug socket mine is too thick walled to get a good grip on it. I gonna try sammitchin the sprocket with black RTV to keep the metal from rubbin the spokes. It don't wobble at all without the outer rag joint. That RTV has held the tensioner without fail as well as the bottom motor mount. The stuff feels as good as any motor mount I have seen on a car. I'll paint the half moon pieces with it and let it dry completely and then gob more on and assemble it wet to pack in there like bearings on car wheels. the rag joint center is exactly the same diameter as the wheel center and the center of the sprocket is the same as the center of the outer part of the wheel bearing cage and does not bind the wheel at all. I noticed I must have lost quite a bit of power using the tensioner it pulled the hill much better without it.
 
george_n_texas said:
Noticed the chain looked real loose when I got there and when I got back seemed tight again...
Click to expand...

Usually this is a sign of an offset rear sprocket and/or the engine is changing position slightly, I'd slowly turn the rear wheel checking to see if the chain's tension changes - this is a easy way to check to see how much/where the sprocket is offset.

It doesn't really matter if the center if these stock kit sprockets are aligned with the hub perfectly as there's no guarantee that they were stamped without flaws. One of my stock ones is badly out-of-round and slightly oval - so there's no getting it right.

I dunno if I'd trust just RTV goo to take the place of one of the fiber reinforced rubber "doughnuts" to sandwich the spokes... doesn't seem like it'd have the strength to do much *shrug*
 
wjliebhauser said:
George,the the actuator lever turns a rod that has a flat side. The flat side is towards the clutch/drive shaft when engaged.......
Click to expand...

There is a ball bearing behind the rod that lets the clutch turn and not transmit that turning to the actuator.
 
Do you have a coaster brake by any chance? I thought for sure that it was my chain making a popping sound. I checked or removed everything that it could be catching on and it still popped. I finally removed the motor drive chain and it still popped when I rode it and pedaled. It turned out to be the mechanism inside the hub. The larger bearing race on the coaster brake clutch was gouged and a bearing was catching on it. I was going to fix the hub but decided to order a Shimano with 12g spokes instead. If you have a coaster brake and can’t find any other cause, check it out.
 
No coaster brakes...one broken master link today though LOL...I may have put it on basackerds. At any rate the popping noise has just about gone I replaced the masterlink with a link from a bike chain not sure how long that's gonna last the chain is the bigger 410 as is the sprockets. When I took off the bracket I glued in with the black rtv the rtv held so well it pulled the paint off the frame. Like I said this is a test bike (like none of the rest of the bikes here aren't LOL) I definately gonna order a new master link just in case.
Thanks for all the help guys you always seem to get me pointed in the right direction.

Has anyone here ever ran with no outer rag joint and seen it grind the spokes?
 
Sounds like the master link clip is hitting the inner wall of the pulley wheel. If so you may need to bend the tension-er clamp very slightly away from the rear wheel. Roll the bike and look at the tension-er wheel when the master link passes it, see if that's the problem.

Make sure the round side of the master link clamp is facing in the direction of the tension-er wheel.


The other way would be to take the tension-er clamp off and torque the tall piece it very slightly CCW.

If your chain is too tight for the amount of alignment you have you may need to give it a little slack.

Good Luck...
Custom Motorized Bicycle Decals - Alternative Transportation
 
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