Chain Binding???

[gary55]

I bought my first 2 stroke engine kit a couple of weeks ago, one of the first things i noticed was the absence of lead in lead out bevels, per ansi standard, on the sprockets, tips of sprockets actually appear to be square.

This would surely lead to a noisy chain at best, and binding at worst .

Has anyone made an attempt to ease these corners?

I got a batch a while back with burred up engine sprockets. Took a dremel to them. Worked great.

 

[gary55]

Good thing they aren't home made helicopter kits.

 

[Lukesky36]

i fliped my bike over and pedaled with my hands this bike was new so no gas, untill the binding subsided some sprockets have tight clearences and the chains you can get are not pre stretched

 

[Sumsloppymeet]

ive been doing like gary and ill round and bevel them smooth em out on any sprocket wiith teeth it get even if its just to leave no sharp corners it gets old having your hands ate up all the time like you went and punched this a/c condenser coil once or twice ouchh

 

[Member 28982]

Sounds like your chain is not tight enough and your chain tensioner is off-balanced. Why else would your chain be kicking up against itself? Too much slack.
I experienced a similar situation a few weeks ago, not that it has anything to do with it but once I painted my rear sprocket, everything tightened up.
It wasn't binding up against itself, it was simply coming off of the rear sprocket, but you got to remember with these tiny unpredictable engines is everything comes down to is the chain engine sprocket even with the rear sprocket tight and when it comes under the rear sprocket over the chain tensioner should be a little loose but from the chain tensioner back into the engine sprocket should be tight.
I ran into this guy who had a rear spring and his chain kept on coming off of his rear sprocket and binding up against itself inside the engine side chain sprocket. I know these aren't the proper terms as somebody will criticize it but whatever y'all get the point.
I told the guy to lose a bike with the rear spring or shock. Maybe your bike doesn't have that ?

 

[LewieBike]

I bought my first 2 stroke engine kit a couple of weeks ago, one of the first things i noticed was the absence of lead in lead out bevels, per ansi standard, on the sprockets, tips of sprockets actually appear to be square.

This would surely lead to a noisy chain at best, and binding at worst .

Has anyone made an attempt to ease these corners?

Yup as a bike mechanic this is the first thing I noticed in addition I'm running 410 KMC heavy duty, BMX freestyle type chains, so my first sprocket was removed for grinding and filing it narrow, afterwards I took the square tips off the sprocket.

Trying to run the stock chain on these sprockets, especially if your engine comes with the weird, narrower width sprockets is asking for engine case damage. It's a serious manufacturing flaw and I don't see how any normal company could possibly sell these without having a multitude of lawsuits. The rear 44 tooth OEM pineapple clamp sprockets are all 1/2 X 1/8 sized and the front sprockets should also come with the same dimensions. The 415 chain these bikes come with are junk, you can't use a normal chain breaker on them so you are left with grinding the pin flush and driving the side plate off.

This weakens an already junky chain. Add to this that none of these engine sprockets are concentric and you have a situation where the average user, who has little mechanical knowledge ends up with a bike with a final drive train that is apt to run poorly, break or jam, damages the rear wheel and the engine. It's unconscionable.

 

[LewieBike]

i fliped my bike over and pedaled with my hands this bike was new so no gas, untill the binding subsided some sprockets have tight clearences and the chains you can get are not pre stretched

Chains should never be 'prestretched' either they fit correctly or there's a serious problem with their fitting to the sprockets and their precision.

Once the chain is 'stretched' it's worn out, and should not be used.

Period.

 

[willis617]

Yup as a bike mechanic this is the first thing I noticed in addition I'm running 410 KMC heavy duty, BMX freestyle type chains, so my first sprocket was removed for grinding and filing it narrow, afterwards I took the square tips off the sprocket.

Trying to run the stock chain on these sprockets, especially if your engine comes with the weird, narrower width sprockets is asking for engine case damage. It's a serious manufacturing flaw and I don't see how any normal company could possibly sell these without having a multitude of lawsuits. The rear 44 tooth OEM pineapple clamp sprockets are all 1/2 X 1/8 sized and the front sprockets should also come with the same dimensions. The 415 chain these bikes come with are junk, you can't use a normal chain breaker on them so you are left with grinding the pin flush and driving the side plate off.

This weakens an already junky chain. Add to this that none of these engine sprockets are concentric and you have a situation where the average user, who has little mechanical knowledge ends up with a bike with a final drive train that is apt to run poorly, break or jam, damages the rear wheel and the engine. It's unconscionable.

So 410 chain is .125 inches betweem link plates?
Is it mportant to specify heavy duty bmx chain?
I wouldn't have thought chain for "pedal powered" bikes would be of sufficient strength or durability for engine power?

BTW, i have no trouble using a chain breaker on 415 chain

 

[LewieBike]

So 410 chain is .125 inches betweem link plates?
Is it mportant to specify heavy duty bmx chain?
I wouldn't have thought chain for "pedal powered" bikes would be of sufficient strength or durability for engine power?

BTW, I have no trouble using a chain breaker on 415 chain

KMC Z410 chains are known for their durability in freestyle use, I've seen how these chains hold up, and they're decently priced and fit all makes of chain breakers, and run flawlessly on all "1/2 X "1/8 sprockets.

My present Cyclo and Bell bicycle chain breakers do not fit the 415 chains that come with these engines.

Maybe you have a universal chain breaker used for motorcycles, in my experience the 415 will not allow you to engage enough threads on the smaller bicycle chain breaker's thumb screw/pin extractor without stripping out the threads in the breaker's body when trying to press out a 415 chain's pin. Also the little roller anvils in these breakers are too narrow to allow the 415 width sideplates to drop down far enough to squarely line up the chain pin with the breaker's extractor pin.

It just doesn't work, I've had to replace my Bell chain breaker because of the 415 chain, it's BS.

 

[willis617]

My chain breaker is not a bicycle chain breaker, so that makes sense now