701 compresion question

[DezKnotz]

ok i bought a ski about a month ago and i think it just dropped the top end. the motor is a 61x with tim jude porting, hot rod crank 46 carb b pipe and a ada head. x2fanatic was riding it and he said she just started to bog out and know it wont start, the compression reads 10 and 60. i hope its just the pistons? what do you think?

 

[DC SUPERJET]

there's only one way to really find out...rip it apart

go out in the garage and take off the head real quick and that should give you a start.

 

[Ericfox]

pop the head off... you'll prob. see what happened....

 

[junkyardj]

ouch! hope you just lost a ring

 

[tor*p*do]

ouch! hope you just lost a ring

or two!
60/10 sounds bad :crying:

 

[Foximus]

On a side note, but somewhat similar. What should piston clearence be on OE pistons and stock bore? .005" ?

 

[brentR]

.0035 to .0045 for oem cast

 

[SUPERTUNE]

Never .0035 unless you have a absolutely bone stock (JUST LIKE IT CAME OFF THE SHOWROOM) .0045 is a much better for the tight side for any modified engine with raised compression and or + a performance pipe.
How old was the Hot Rod crank? They're good for about 2-3 seasons for me. Then the bearings go bad....

 

[Freakrider]

Never .0035 unless you have a absolutely bone stock (JUST LIKE IT CAME OFF THE SHOWROOM) .0045 is a much better for the tight side for any modified engine with raised compression and or + a performance pipe.
How old was the Hot Rod crank? They're good for about 2-3 seasons for me. Then the bearings go bad....

is that because when u look at the box it says made in Taiwan ?

 

[DezKnotz]

idk how old it is 2 years

 

[DezKnotz]

oooooooo i lost a ring all rite, the other piston looks ok but their is a small indent in the sleeve

 

[Foximus]

Chuck... just to be sure, you are talking .0045 INCH correct... ?



I dont like to make the mistakes NASA made.

 

[Ericfox]

yeah inches...