Chain Noise

[Dr. J.]

Inspecting my front drive sprocket I found abnormal wear using 415 (wide) chain. After 249 miles using 415 chain, my kings 80 cc motor was becoming very noisy. The sprocket had wear marks underneath the teeth on the shoulder. The chain was riding too low. If you take a good look at the relationship of the chain to sprocket, you can see where the chain rubs too low on the sprocket.

To fix this problem, I machined about .045 from the sprocket width to end up with a sprocket to accommodate the use of narrow chain. I chose high strength BMX bicycle chain. The chain I used was KMC Z510H 1/2 x 1/8 inch.

In conclusion, the bike was faster and resulted in a 70% noise reduction. Also, chain stretch is nil.

Dr. J.

 

[gone_fishin]

welcome, Dr. J

that's some great info...thanks very much!! 8)

 

[gone_fishin]

by golly he's right!! the larger chain also wears a groove inside the cover-plate, nice catch... 8)

 

[Dr. J.]

This may be the cause as to why the 415 stretches continually. The BMX chain (Z510H) has no bushings, extremely strong, and very light weight.

Dr. J.

 

[gone_fishin]

i'm bumping this because it's an important issue...at 100 miles i already had a groove going on the inside of the cover. that HD chain's cool, but way too large.

 

[mrsaxman99]

could you possibly post a picture or two showing how you modified the drive sproket?

 

[gone_fishin]

fyi-i was lucky to have available an old chain off a worksman tandem...i didn't make any modifications to my drive sprocket, it just went right on there 8)

 

[blompod]

good to hear that it goes straight on the front drive sproket, I was trying to fit that big stonkin chain today and cant see how it would even go round the drive sproket and clear the casing. Im off first thing in the morning to grab a bmx chain. As my bike comes together its really starting to look like a little retro motor cycle, hope I dont get busted. But it looks way cool.

 

[alesterfeind]

I just came across this today and wanted to find out how well other chains have worked. So some of you have used bicycle chain instead of the HD chain that comes with the kit? If so, which chains have worked best and not broken? I notice the mentio of BMX chain Z510H. Thanks for any information.

 

[azbill]

I have been running the Z510H chain for well over 1000 miles now, it has never stretched, or given me any probs
they are made for stunting bmx's, and are designed to handlke the torque of landing
I would not hesitate to reccomend it to anyone
they are really cheap from www.bikenashbar.com (I think I paid 6-7$)