Engine Problem

[Russ2251]

I consistently use #35 chain and have never suffered breakage. Use chain lubricant...not oil. Regular oil attracts dirt and grit.
HKK chain is what I use.

 

[jr dragster T]

He's using #25 chain, No wonder it breaks on a kart.

 

[r_chez_08]

which is stronger, #25 or #219

 

[Russ2251]

#219 is about double the strength (more?) of #25.

 

[JROY82]

I am only using the #25 chain because it is what the original jackshaft on the pocket bike had. It is obviously not my preference. I run #41 from clutch to jackshaft. I havent been able to find a #41 or #35 rear sprocket to fit the bolt pattern.

 

[Russ2251]

I have run across blank sprockets meaning your bolt pattern could be machined in.
If I can find the link I will post here.

 

[Russ2251]

Found it:
http://www.jackssmallengines.com/gokart_alumsprkt_35f.cfm

 

[JROY82]

Quick update on the chain issue. Its actually not #25 its like a metric size of #35 so it is decent sized chain but not so easy to find. I apparently have never seen #25 chain and I now see why no one would use it.

 

[ZnsaneRyder]

Second or 3rd time I've read posts about chain breakage.
What's going on here?

I believe it's because most use don't use a strong #35 or #40 chain, and also probably don't lube their clutch often, so it chatters and engages too hard and puts considerable shock on the chain.

A dry clutch flops a chain around, and makes a lot of noise, and a bit of WD-40 on the bushing AND friction surface before running that day, makes for a smooth engagement & takeoff and by the time it burns off, it still is fairly smooth before needing it again.

 

[Russ2251]

Chain lube works best.
Clutch just needs a couple drops of sae 30 on bushing every few hours of operation. Shoes never need any oil if properly maintained. Clutch should never chatter. Chatter indicates damage from overload.