Chain Problem - Stumped.

[Deleted Member 4613]

I'm getting ready to test the Oilite bushing I installed. The bike rolls
nicely but I have a weird chain issue. The chain seems to want to crawl
up the drive sprocket, doesn't operate smoothly. The tension is right,
I have it lubed, the alignment is good, just don't know what is causing it.
Maybe it's a lousy Chinese chain that came with the kit or a bad drive sprocket.
As much experience I have building these, I'm stumped. Any suggestions?

 

[Chainlube]

Is the tensioner on the bottom of the chain? Free the chain from the wheel sprocket and roll it on the trans sprocket to check if it's the right chain.

 

[Deleted Member 4613]

Yes, the tensioner is on the bottom in the normal
position, but I will try rolling it over the drive sprocket.
It seems to roll well over the rear sprocket. I wonder if
it will work in and run smoother after a little use, when it
stretches..

 

[Sidewinder Jerry]

You are discovering chain suck. Look for any rough abnormalities in the drive sprocket and rough spots in the chain. Did you clean the sticky protective coating off of the chain then lube the chain well with a quality chain oil?

Chains technically don't stretch. As a chain becomes worn the pin holes go from being round to oblong shaped. Which causes the gaps between the rollers to vary.

Slowly turn the drive system when you see a chain suck examine that area for abnormalities. You may be able to fix the problem with files or a rotary tool.

 

[Tyler6357]

It sounds like the drive sprocket isn't made to spec, find out which tooth is causing the chain to bind and use a file to file off the metal until it will run smooth.

 

[Member 30571]

What Tyler said ^^^^. I had the same problem before.... 1 tooth was longer than the others and making it bind up.

 

[Deleted Member 4613]

This is going to be very difficult if filing is necessary. I may have to
remove the motor from the bike. Yikes! I saw other areas where the
the Chinese specs were off, like mounting the muffler which I barely
got to fit. I may buy a different 4 stroke muffler.
I have to say the tensioner was much better than prior
models; it had an allen hole to tighten it from the back and front.
The kit was also missing the bottom bracket axle which I had to
buy. The seller gave me $10 to buy the part, and responded
quickly. I will work on the chain problem today and report
the what happens. Putting the bike together seems more
difficult with this kit than moding it to accept an Oilite
bushing. Thanks for all your suggestions.

 

[Tyler6357]

This is going to be very difficult if filing is necessary. I may have to
remove the motor from the bike. Yikes! I saw other areas where the
the Chinese specs were off, like mounting the muffler which I barely
got to fit. I may buy a different 4 stroke muffler.
I have to say the tensioner was much better than prior
models; it had an allen hole to tighten it from the back and front.
The kit was also missing the bottom bracket axle which I had to
buy. The seller gave me $10 to buy the part, and responded
quickly. I will work on the chain problem today and report
the what happens. Putting the bike together seems more
difficult with this kit than moding it to accept an Oilite
bushing. Thanks for all your suggestions.

Yeah, I don't think China ever calibrates their machines. I have gotten parts that are so far off spec that they were unusable. I know it's cheap, but there is no quality control at all in these Chinese factories. Also, their steel making process leaves alot to be desired. I think they are 'thread challenged', haha, sometimes it best to replace their screws and nuts with good ones from the hardware store.

 

[Deleted Member 4613]

Well, here's my report. I used a dremel and did the best I
could. I found two teeth on the drive sprocket that are slightly
out of position. I eliminated about 75% of the problem but
still have some chattering, so I will order a new 10 tooth
drive sprocket. The engine is great, very impressive. It
started on two pulls, idles smoothly, and I felt the power
when the clutch caught. The good news is I checked the
operation of the Oilite bearing and the additional parts
I installed and there was zero movement of the clutch bell
from side to side, no contact between the clutch bell housing
and the spacers I used. The larger pulley definitely stabilizes
the small one totally. Now I'll proceed forward and ride the bike
to further test the Oilite bearing. If the Oilite bushing
performs better than a greased bronze bushing, that
would be a significant improvement in the belt
drive. I also upgraded the carb by drilling out the
fuel jet to 0.026 and drilled holes in the outer filter
cover and put in a high flow filter. So far, so good.

 

[Tyler6357]

Well, here's my report. I used a dremel and did the best I
could. I found two teeth on the drive sprocket that are slightly
out of position. I eliminated about 75% of the problem but
still have some chattering, so I will order a new 10 tooth
drive sprocket. The engine is great, very impressive. It
started on two pulls, idles smoothly, and I felt the power
when the clutch caught. The good news is I checked the
operation of the Oilite bearing and the additional parts
I installed and there was zero movement of the clutch bell
from side to side, no contact between the clutch bell housing
and the spacers I used. The larger pulley definitely stabilizes
the small one totally. Now I'll proceed forward and ride the bike
to further test the Oilite bearing. If the Oilite bushing
performs better than a greased bronze bushing, that
would be a significant improvement in the belt
drive. I also upgraded the carb by drilling out the
fuel jet to 0.026 and drilled holes in the outer filter
cover and put in a high flow filter. So far, so good.

That sounds good! I recommend that when you get the new 10 tooth drive sprocket, spin it along the chain to see if it too might need some shaving before you put it on.