Chain broke while going 110 on I 75 south of Toledo.... why does this happen

[koalaKid]

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This makes no sense at all. If the chain broke, there are now two ends to the chain. Pulling the clutch in does not release the rear sprocket from the rear wheel, so the wheel will still be locked up. And even if it did magically release the rear wheel, the chain cannot stay on the now turning sprocket, and since it is broken, it must eventually come off the rear sprocket. I have zero experience with Harleys, but, what about the primary? Is it still a chain driven component? Could he possibly be referring to that? But even if he was, once the chain is off it is off. No matter what chain it is, if you continue to rotate one end, the chain will come off, or jam solid and stop that piece from rotating.

my guess (considering no photos):

chain snaps, presumably on the top loop. release of tension causes the free end at the front to fly forwards, jamming the front sprocket to the transmission output, thus locking it. i can kind of visualize a rear wheel spinning at the appropriate rpm for the bike to travel at 110 kph, with the momentum of the bike providing torque at the rear wheel. At the same time, the engine is still connected to the transmission, which is creating torque on the front sprocket.

once the clutch is pulled, the torque on the front sprocket is released, allowing it to rotate freely without any external force (ie, the engine). with this, the chain is loosened enough from the rear wheel that it falls off that end, but is still jammed somewhere in the casing around the front sprocket.

**** i dunno man, but the first half of your post seems to me like you're saying the OP is making this s*** up.

to the OP, I thought most sportsters had a belt final drive?

glad you're okay.

 

[08CBR1000]

This happened to me 3 weeks ago on the track, the chain broke at the master link and the chain smashed my casing, slave cylinder and push rod. The only thing that I can figure out is that the the master link rivet was pressed on too tight and the mushroom broke off and the chain split. In your situation it could be something as simple as a rock being flipped up into your chain and sprocket which may overstretch, weaken and broke the chain, there could be several reasons why.
Never cheap out on tires, chains, sprockets or brakes!
It could of been alot worse, glad your OK.

 

[bobjohnson]

How much would it cost to get this done somewhere?

Please please please tell me youre not riding the bike without the masterlink properly clipped or riveted in... If you are, you are just ASKING to have that chain fly off and destroy either your leg or the engine casings, or fly off and kill someone.

 

[SkyRider]

at least the chain didn't hit the engine and make a hole in the case

 

[bear22099]

my guess (considering no photos):

chain snaps, presumably on the top loop. release of tension causes the free end at the front to fly forwards, jamming the front sprocket to the transmission output, thus locking it. i can kind of visualize a rear wheel spinning at the appropriate rpm for the bike to travel at 110 kph, with the momentum of the bike providing torque at the rear wheel. At the same time, the engine is still connected to the transmission, which is creating torque on the front sprocket.

once the clutch is pulled, the torque on the front sprocket is released, allowing it to rotate freely without any external force (ie, the engine). with this, the chain is loosened enough from the rear wheel that it falls off that end, but is still jammed somewhere in the casing around the front sprocket.

**** i dunno man, but the first half of your post seems to me like you're saying the OP is making this s*** up.

to the OP, I thought most sportsters had a belt final drive?

glad you're okay.

I am saying he is telling a story that can only be fiction as told by him. His story makes no sense as told. Because it makes no sense, very little real advice can be given. He needs to not try to be fancy with the story, just give the facts, even if they make him look bad. Unless you can explain how it can possibly happen, your attempt also does not make sense does it?

 

[haisam10]

Please please please tell me youre not riding the bike without the masterlink properly clipped or riveted in... If you are, you are just ASKING to have that chain fly off and destroy either your leg or the engine casings, or fly off and kill someone.

K master link is clipped on the chain and I also have the rivet link on hand. Wats the benefits and drawbacks of clipping and riveting the chain?

 

[GreyGhost]

Pros:
Clip is easier to take off to clean/lube/replace the chain. Rivet done properly doesn't fail.

Cons:
Clip done properly can ocassionally fail. Clip done improperly is almost certain to fail. Rivet has to be cut off. Rivet link needs special tool to attach.

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