piston help

[mdh23jr]

i have a new weisco piston im putting in and there is an arrow on the top of it. anyone know which way the arrow points too? the carbuerator or the exhaust?

[Honda 250r 001]

Exhaust.

[randelator]

Originally posted by Honda 250r 001
Exhaust.

x2

[mdh23jr]

ok thanks. just curious. what would happen if you have the arrow the opposite way?

[randelator]

you will seize your engine, and the ring could gripp in the tranfer port!!

[leager-n-ky]

Your piston would hit the crank, the half moon cutout in the piston skirt has to be towards the carb.

[fearlessfred]

Originally posted by leager-n-ky
Your piston would hit the crank, the half moon cutout in the piston skirt has to be towards the carb.

just wandering,how would the piston hit the crank

[leager-n-ky]

When the piston is at the bottom, and starts back up, the crank goes more towards the back of the motor before it starts coming up, this is when it would hit the piston if it were in backwards.

[Honda 250r 001]

Originally posted by leager-n-ky
When the piston is at the bottom, and starts back up, the crank goes more towards the back of the motor before it starts coming up, this is when it would hit the piston if it were in backwards.

hmm. thats weird! my 125 ran with the piston in backwards. haha.

[fearlessfred]

Originally posted by leager-n-ky
When the piston is at the bottom, and starts back up, the crank goes more towards the back of the motor before it starts coming up, this is when it would hit the piston if it were in backwards.



no

[leager-n-ky]

Originally posted by fearlessfred
no

So you are telling me this wont/cant happen???
Take your piston, put it on backwards, leave the head, and the reed cage off, and rotate the motor, if you watch inside the intake you will see that YES, it can, i have fixed bikes, where they have done this, brand new piston's put in backwards, break off skirts.
You think i just dreamed that one up??

[Honda 250r 001]

Originally posted by leager-n-ky
So you are telling me this wont/cant happen???
Take your piston, put it on backwards, leave the head, and the reed cage off, and rotate the motor, if you watch inside the intake you will see that YES, it can, i have fixed bikes, where they have done this, brand new piston's put in backwards, break off skirts.
You think i just dreamed that one up??

R u sure the piston skirt hit? or did the ring catch on the exhaust port and make it look like the skirt was hitting?

[fearlessfred]

[QUOTE]Originally posted by leager-n-ky
So you are telling me this wont/cant happen???
Take your piston, put it on backwards, leave the head, and the reed cage off, and rotate the motor, if you watch inside the intake you will see that YES, it can, i have fixed bikes, where they have done this, brand new piston's put in backwards, break off skirts.
You think i just dreamed that one up?? [/QUOTE
yes thats what i was saying, but i will do what you are saying . im going to freshen the top end of my desert sled soon and right or wrong i will post my findings ( without rings )

[86 Quad R]

i'm going to mok one up this evening to satisfy me own curiosity. :cool: lol

[fearlessfred]

RIGHT ON

[86Rrider]

I'm putting my top-end back together on my '86 now (currently waiting on a replacement Cool-Head o-ring to show up) and something that is also very important is to make sure that the 3 oiling holes are in the piston skirt on the exhaust port side, to keep the transition lubed for the rings. If your piston does not have the holes, see the little sheet of paper that came with the new Wiseco piston to see how and where to put the holes.