Now I'm really worried HELP! 1/7/7 UPDATE!

[bird]

I don't know what's causing it, but it is still behaving very strangely. When I go to start the bike, the first attempt will lock the back wheel completely - I then recover, get back up to about 3 or 4 miles an hour and pop the clutch and the second time she starts humming.

It's bizarre and it's almost every other time, sometimes 2 out of three tries end in failure with the back wheel locked up, but then it goes and it's great. I'm stumped - anyone else have this happen?

my friend brought his bike over tonight and its doing the same thing. i took the motor apart and the pushrod is sticking hard enough in a certain spot to lock up the back wheel and it wont roll over.
it happened a couple times and i would have to roll it backwords to get it unlocked i put a little oil in the holds on the bottom of the pushrod and it seemed to work but i cant realy tell at this point the motor is still not starting because the magneto it ruined. tomorrow i will get a new one and ride the the bike and see if the sticking goes away.

 

[sideshowsideswipe]

what is the pushrod? forgive my ignorance...


And I couldn't get it unlocked to use it today so I have to work on it tonight...



I'll try oiling my pushrod and maybe work on the bike too...

 

[tirebiter]

I'll try oiling my pushrod and maybe work on the bike too...

 

[bird]

inside the motor the arm that connects the piston and the crank.

im pretty sure this kids motor is not going to make it i did probably everything i could think of but im sure the bearings are fryed. the piston had alot of scratches and little nicks in it like gravle cycled threw it then, everything is messed up on this motor except the cylinder so im guessing someone rebuilt a almost dead motor with some new parts and sold it to him.

 

[sideshowsideswipe]

that sucks I think kings motors sells the upper assembly separately...and I saw a lower section of a grubee going for $25 on ebay recently

 

[sideshowsideswipe]

Ok today I got her going again I'm taking her to work and hoping that it takes me back home again at 8pm tonight...

 

[psuggmog]

The "pushrod" is conventionally known as a connecting rod or "con"rod.

 

[sideshowsideswipe]

(image from GRUBEEINC.COM of the STARFIRE engine)

So the conrod is number 26 right?

 

[Steve]

OH my God! Look at that drawing, there is no counter ballance on the crankshaft and the crankshaft is three pieces. THAT's why they shake like a dog s#!ting a peach seed!

 

[psuggmog]

#26 is the connecting rod. Multiple piece cranks is the norm for two strokes, nocounter weights isn,t.