Chains Chain jumping teeth

I'm not saying it's not a stiff link, probably is... But dealing with these P.O. cr@p engines for a few years here are a few other reasons where i have seen this before.

The idiot manufacturers/supplies from china shipped you a #40 chain, not a #41. Some have said over the years they are the same, there not.

Or, When you get rolling and the chain gets into a bouncing rhythm it hops/bunches the small sprocket and jams.

Or, the chain picked up a tiny piece of debris sucked it into the sprocket and caused a jamb. Unlikely but has happened.

Or, alignment from the rear sprocket to tensioner to the small sprocket is off slightly bunching the sprocket.

Or, engine is mounted slightly crooked causing the chain to twist slightly causing tension on the chain pins making them stiff as they pass the sprocket, bunching the chain

Just saying... all of these things have happened to me, but I agree its probably a stiff link. LOL
 
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My two favorites are Prolong and Triflow, but there are dozens of other really good chain lubes. Just wipe off as much excess as you can. Too much flings off all over everything and collects more grit.

If you find a stiff link, flex the chain back and forth sideways at the tight link, in the direction it's NOT supposed to flex. This will loosen the tight link right up. After adding or removing links with a chain breaker the link is always too tight. A little gentle sideways bend and flex will fix that.

I have used a chain breaker tool on numerous links of this chain. First to get the initial length. Then again several times after I made my new tensioner. And then there was the broken link I had to remove. I spliced back in pieces that I had left over.

I'm not saying it's not a stiff link, probably is... But dealing with these P.O. cr@p engines for a few years here are a few other reasons where i have seen this before.

The idiot manufacturers/supplies from china shipped you a #40 chain, not a #41. Some have said over the years they are the same, there not.

Or, When you get rolling and the chain gets into a bouncing rhythm it hops/bunches the small sprocket and jams.

Or, the chain picked up a tiny piece of debris sucked it into the sprocket and caused a jamb. Unlikely but has happened.

Or, alignment from the rear sprocket to tensioner to the small sprocket is off slightly bunching the sprocket.

Or, engine is mounted slightly crooked causing the chain to twist slightly causing tension on the chain pins making them stiff as they pass the sprocket, bunching the chain

Just saying... all of these things have happened to me, but I agree its probably a stiff link. LOL

I could be wrong, but I think my supplied chain is a #415. I'm not a roller chain expert, but I'd never heard of #415 chain until I bought this kit. And you're right, #40 and #41 chains are different. My friend and I learned that on his go-cart when we were 12.

My chain tension is good... really good since I made the new tensioner. But I know I've been having problems with my chainline. I got most of it worked out. My bet is that you and the others are right and I have a stiff link(s). But the chainline would get out of alignment because the engine would torque to the sprocket drive side when I would release the lever to start the engine. This problem happened after the engine had been torqued over.

I ordered a new rear hub and sprocket from Pirate Cycles which should be here tomorrow. I'll get those parts installed and then work my way forward to get the chainline perfect.

Btw... the Bevis and ******** in me is still giggling about "stiff link". HA!
 
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Cr@p!!

Alright guys... I think I'm just going to pick up a USA made #41 chain.

Took the bike out tonight for a short cruise. Chain broke! No studder, no snapping sounds... nothing. RPM's shot up and speed dropped. That was it. It was dark but I found the chain. Because it happened so innocently, my initial thought was that the master link became loose and fell out. Nope! As you can see in the pic, the chain broke right next to the master link.

The other photo of the link pieces are from the first time the chain broke... in the daylight so I found the pieces.
 

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Joe
On the new chain don't make it to short and then have to add back ,because every time I have added links, that link would be tight so your better off not to add links if you don't have to.
 
Ahh, the weak link. Maybe the pin was 1/4 way out and you didn't notice it. The chain tunnel is tight... maybe the pin sticking out a bit was causing it to jamb in the tunnel. Now I guess you throw out that "possessed" chain and make a trip to tractor supply for a good #41. Maybe have a Priest bless it while your at it. Ha!
 
Cr@p!!

Alright guys... I think I'm just going to pick up a USA made #41 chain.

Took the bike out tonight for a short cruise. Chain broke! No studder, no snapping sounds... nothing. RPM's shot up and speed dropped. That was it. It was dark but I found the chain. Because it happened so innocently, my initial thought was that the master link became loose and fell out. Nope! As you can see in the pic, the chain broke right next to the master link.

The other photo of the link pieces are from the first time the chain broke... in the daylight so I found the pieces.

Problem solved :>)
 
Chain.

Joe, If your engine is still moving around, even a little bit, It could be part of the problem. Every time the engine moves (even a little bit) it throws the chain out of alighnment. To check this I grab the the top of the frame and the engine head, (wait till it cools off,) and try to make it move. If you can make it move by hand it will surely move when riding. The engine CAN NOT move AT ALL.
Everyone is giving great advice about a tight link, but I've found a link has to be REAL,REAL, tight to jam it in the case. This is a possiblity with the POS chain that comes with the kit. If you can wiggle the links back and forth with your fingers, then it's probably not tight enough to jam. the tension and pull of the engine is A LOT more than you can do with your hands only. I get tight links all the time and I just use a punch or chain tool to loosen it, soak it in chain lube and work it back and forth a few times. Just make sure the chain pins are even on both sides when yer done.
Just my opinion, (I have been known to be wrong at times,) But it really sounds to me like a combination of cheap chain and engine alighnment. Get a better chain and REALLY TUG on your engine to make sure it's tight. And, If you have to, get a straight edge to check engine/ rear sprocket alighnment. I mostly just eyeball it, but a straight edge would get it closer. And last, But not least, especially if you're using a rag mount, Make very sure you're not getting a back and forth or side to side movement in your rear sprocket. Back and forth will put way too much pressure on the chain. side to side will take it out of alighnment every time the sprocket goes around. It's almost impossible to get a rag mount perfect, but it has to be very, very close. At times I've spent 3 or 4 hours on a stubborn rag mount trying to get it just "good enough". As soon as you can you should go with a hub mount system if you haven't already. Good Luck.
Shiney Side Up,
Big Red.
 
Joe, If your engine is still moving around, even a little bit, It could be part of the problem. Every time the engine moves (even a little bit) it throws the chain out of alighnment. To check this I grab the the top of the frame and the engine head, (wait till it cools off,) and try to make it move. If you can make it move by hand it will surely move when riding. The engine CAN NOT move AT ALL.
Everyone is giving great advice about a tight link, but I've found a link has to be REAL,REAL, tight to jam it in the case. This is a possiblity with the POS chain that comes with the kit. If you can wiggle the links back and forth with your fingers, then it's probably not tight enough to jam. the tension and pull of the engine is A LOT more than you can do with your hands only. I get tight links all the time and I just use a punch or chain tool to loosen it, soak it in chain lube and work it back and forth a few times. Just make sure the chain pins are even on both sides when yer done.
Just my opinion, (I have been known to be wrong at times,) But it really sounds to me like a combination of cheap chain and engine alighnment. Get a better chain and REALLY TUG on your engine to make sure it's tight. And, If you have to, get a straight edge to check engine/ rear sprocket alighnment. I mostly just eyeball it, but a straight edge would get it closer. And last, But not least, especially if you're using a rag mount, Make very sure you're not getting a back and forth or side to side movement in your rear sprocket. Back and forth will put way too much pressure on the chain. side to side will take it out of alighnment every time the sprocket goes around. It's almost impossible to get a rag mount perfect, but it has to be very, very close. At times I've spent 3 or 4 hours on a stubborn rag mount trying to get it just "good enough". As soon as you can you should go with a hub mount system if you haven't already. Good Luck.
Shiney Side Up,
Big Red.

Yeah, the chainline has been a problem... mainly from the engine moving. I was out of town this weekend so I didn't get to play with the bike. But the brown truck did deliver my new hub, wheel and sprocket from Pirate. That should be a big improvement! One night this week or maybe next weekend, I'm going to fabricate a top motor mount. Hopefully that should solve the problem. Probably also going to fabricate lower motor mounts too. No more clamp around the frame.

Thanks,
Joe
 
Engine Mount

Joe, I'm not sure what you have in mind for an engine mount, But whatever you do, DO NOT drill a hole in your frame. You can go with a better grade stud and nut that will allow you the extra torque needed . You can also use a U-bolt type mount on the front mount. e-bay has a dual U-bolt type that I'm thinking about for my new build. (Item #150716824212.) But at $15 I can make my own. The two U-bolt type has two points of contact that should prevent the "swivel" effect you get with most mounts. I've also seen some mounts welded directly to the frame. With a good steel frame, a couple peices of good steel,(one front, one back,) a drill press and a welder you can do a mount that Zeus couldn't move. (I hope you ARE using a steel frame.)
Knowing you haven't got the engine tight yet tells me A LOT. I think MOST, if not all of your chain problems are from your engine/rear sprocket alighnment stemming from engine movement. A hub mount and chain upgrade is the best way to go, but it won't do much good if your engine is moving around. It will still twist the chain into catastrophic failure, even a good chain.
Let me know when and how you finally get yer engine tight and take it for the first test ride. I think your first words after that are gonna be YAAAHOOO!!!
Shiney Side Up,
Big Red.
 
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Well I got my solid motor mounts finished. I'm pretty happy with them. The engine no longer torques over. The isolaters allow for just a little movement. Put the new #41 chain on as well. Much better quality that the original chain.

I'll post a couple pics here, but I've already posted all the pics in an album.

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