Chain slips off rear sprocket

[Randolph]

I'm am desperate for some help here and need some advice. I have a 49cc 2 stroke bike motor attached to a 26 inch giant beach cruiser bike. Everything is hooked up ready to go but no matter what I do my chain continues to slip off the back sprocket. I bought a spring chain tensioner which helps a little but like I said no matter what I do I can't get it to stay on. I am starting a new job soon and I need it to get there and back and am worried it won't make it there. If anyone has any advice please let me know. Just to play it safe I am buying a heavy duty chain and me sprocket my old ones have been scratched up a bit trying to get it to work. Thanks guys. I will take pictures and add them in a bit.

 

[Kpi890]

It may be that your drive sprocket and tear sprocket aren’t lined up straight. Look from the back of the bike straight down the chain and see if the two are in line.

 

[Tyler6357]

It could be that your chain it too tight, try lowering your chain tensioner and loosing it, the chain should have some slack in it.

 

[Leon Flores]

I think chain alignment is your problem like kpi890 suggested. Also I think the chain shouldn't be too loose. I've seen videos where the chain is loose on the tensioner. The way I set it up there was little play, harder to pedal, but never came off the sprocket!! Oh and it went 35 mph, mine was a 4 stroke though but when talking about chain and chain tension it's the same.

 

[inspectorcritic]

Could be your tire crooked in the bracket or your rag joint is crazy out of wack raise your bike spin you tire use your thumb nail gradually move thumb in 1/16" of inch if it drags then gaps out tighten the nuts until it's true track.