IT DIES!!!

[turtle13]

So I'm rolling home from the store today and decide to take the "long way home"... of course this way includes a long hill... half way down the hill it starts to sputter. I think "why have I not fixed the gas gauge yet?". It then completely dies and I pull into a parking lot and try to kick it over... nothing just the sound of the drive face spinning... awesome...
So I have concluded that either the threads sheared off the crank, the nut came loose, or that the crank sheared completely. The belt still seems taught, so I don't think it is the later.
The unfortunate thing is that I can't even pull it apart till late tonight at the earliest...
Pics and update to come.

[RZRob]

Bummer. I guess I don't understand why the external failures you're describing could cause the engine to sputter and die. Perhaps if the crank snapped in such a position that the ignition pick-up etc., doesn't get a chance to do its thing anymore that might explain. I'm still new to these to understand their failure points.

RZ Rob

[odinxxix]

well i hope for the best and the nut just came loose. that elite/kymco was a cool build and seemed pretty quick! plus the 12" tire on the back and 10" on front what a stance. o BTW turtle what year is your elite and what engine did it have? vari or no. i may have a chance to get one identical to yours. or one with the af16 who ever is willing to negotiate the selling price.

[turtle13]

I don't see any correlation between the two either... my only thought was that possibly the nut came off and jamed in the vari causing it to sieze momentarily. Thus making it loose spark or something like that...
Unfortunatly this is not on an elite, this is on my 85 aero 50. If someone wants to give me a dio than I will surely make it af16 powered, but after this weeks vet fiasco with my dogs and 2000$ later... I am crossing my fingers its just the nut, as there is no such thing as expindable cash.

[evilone]

Soft seize and clutch kept the belt turning after motor stopped which caused threads on crank to strip? If you kick it and hear the drive pulley spinning then i doubt the nut fell off. Just my guess since you said,

"So I'm rolling home from the store today and decide to take the "long way home"... of course this way includes a long hill...

Going down long hills is not good, were you at WOT going down hill?

[turtle13]

Soft seize and clutch kept the belt turning after motor stopped which caused threads on crank to strip? If you kick it and hear the drive pulley spinning then i doubt the nut fell off. Just my guess since you said,

"So I'm rolling home from the store today and decide to take the "long way home"... of course this way includes a long hill...

Going down long hills is not good, were you at WOT going down hill?

Got the belt cover off, sure enough it has stripped splines... vari off and pushed the drive face onto the remaining splines and turn by hand. Feels like compression is up, which would indicate a soft seize. Can't test just yet as I can't turn the motor by kick or electric starter. Guess its time to get a new crank, split the cases, and start from 0...

[evilone]

Ouch.

[eliteguy50]

If the crank is no good, you can always weld a disk on to wrap a cord around or pull the head to check the top end.

[turtle13]

well here we go...

going to try to get the drive face on to where i can crank it with the electric starter and get a compression reading on it.
what really sucks is that the temp gauge stopped working on the ride TO the store...
so im not really sure on how hot it was running at the time.
the only real thing that doesnt make sense is that if it were to seize hard enough to strip the splines on the shaft, then it would have come to a sudden halt, or i would have at least had a rear wheel hop when it seized.

[Wheelman-111]

Greetings:

A couple theories:

If the splines were misaligned when you tightened the nut, it's possible that the splines munched each other as you tightened. That's why it's important to make some slack in the belt and verify the outer pulley fully seats on the crank shoulder.

If the nut simply wasn't tightened, it could drop between the outer pulley teeth and the cover, jamming the pulley. Crank momentum at 6000RPM would do the rest. The engine might stall abruptly, like a seize, but the belt would be disengaged by the loose pulley, and there'd be no skid.

Check for a nut-sized notch inside the cover and/or case belt cavity.

Sorry for your loss. Some have posted about welding the pulley to the shaft. You can still change belts by removing the clutch and spreading the rear pulleys. Fix it right in the off-season.

[tazland001]

Its called lock tight. Use it and you wont be disapointed. Been there done that.

Taz

[turtle13]

the funny thing is, when i took off the drive face last time to change rollers, i thought in my head "lets make sure the splines mesh perfectly since i have had this thing off like 20 times in the past month"... fat load of good being cautious does! loctite will be going on every time from here on out though.
it could have been a seize, but i have taken this hill plenty o' times in the past and not raise but a hair above cruising temp... and that was with the 11:1s. I am stumped at how it happened, but it happened, and hopefully tw39515 may have provided me an answer out... however i may have to become a "Tortoise of the night" to do so.

[Lunytune]

I had what I thought was a seize last fall. When I finally got around to pulling it down, found piston going up and down when it wasn't supposed to. Bad rod journal. It's worth checking while you've got it down.

Wheelz, "wait til the off season"? Geez, it's June. Off season is a long ways off.

[Wheelman-111]

Greetings:

I meant that welding on the outer pulley would get a person through the summer, while the hunt for a new crank can begin today. The crankshaft is composed of 5 big pieces and does come apart with the right press. Only one of these - the Variator end splines - is munched. Even the current crankshaft can be rebuilt if just that shaft segment can be sourced from a crank with a bad big end, for example. Just thinkin' out loud ... er, keyboarding my errant thoughts.

[turtle13]

Well some "bigger" things will be in route through UPS shortly. So I won't be with out for to long... it should suit my pipe better too, making it "hit" lower in the power band. The past couple of nights have proved that the wild lion didn't really come in till wayyyyyyy high in the power band. Which may have led to its demise. But I'm sure the tuning won't end anytime soon, once I put the 10:1s in it, rejet for pipe and tune the rollers in, I imagine that it will be time to rip it apart and rebuild over the winter...
But the pros of the situation.
No more stripped carb holes (I think)
No more 2 bolt intake
Can actually get some performance reeds/put on a non restrictive intake manifold
Bigger bore so the pipe is better suited to the engine

The cons.
The end of my quest of how far I could push 50cc's (which I feel I did pretty well, minus the whole breakdown part of it...)