Have you ever seen....?

Well, I have an 03 blast with about 4k miles on it. Use it occasionally as a backup bike. Son started riding it this year and while it kept popping off the carb to the intake boot, so he carried tool with him to put it back on. Happens when it would backfire, BAM - off goes the carb.

Last night he was coming off an off-ramp from the highway, slowed down for a curve, down shifted, and BAM. didn't know what the noise was but didn't have any power as the bike was still running, slowing down and down shifted again. seems like its stuck in neutral until he looked down at the Primary case because of a noise. and sees this.

Attachment 8410

Stops and calls me to come get him. I have no idea what happened, but got it home and saw this:

Attachment 8411

Some how the primary chain broke, either something in the engine froze and caused the primary chain to break or the primary just broke. Either way I would imagine it would take a crap load of force to break the primary chain.

I haven't had time to take it apart and try to find out the root cause, but I'm kinda looking forward to it.

Curious if anyone has any experience or have heard of this happening along with the root cause.

Been following the Buell movement for over ten years and this is the first time I've seen such primary destruction!
I'm curious to see what you discover when you start taking the primary apart.
4K miles on the blast? Geez... ...normal riding, right?

Root cause starts with with the Carb was blowing off , What ever was the cause that issue got worse, Going 60 or so when your son let off the throttle Bamm sent a jolt through the primary chain, popped it wrapped it around the crank sprocket and broke through the case. keep us posted, I am guessing was caused the carb blowing off is culprit to the prim chain and case.

reach out for jetlee. board member well versed in blasts. root causes? faulty intake boot....faulty ignition module....tps not reset to specs. all 3 individually or combined will cause severe back-firing/after-firing and eventually tear up alot of **** including the primary drive assembly.

This pisses me right off.

The carb popping off was due to fuel mix being too lean. Seeing as it kept happening, YOU should have known to fix it before letting someone else (especially your kid!) ride it on the regular. No vehicle has parts that just randomly pop off for no fucking reason.

As for that chain...considering your inattention to the carburetor, it was probably too dry, too tight, and as Silverrider said above the shock from the backfire caused it to pop.

I'm glad your son wasn't hurt as a result of your inattention to maintenance. Shit like this is why I don't want to sell my bikes.