Custom/Hybrid Canadian Freestyle ROK Rebuild

steve-uk

Manners cost nothing
Location
Barrie - ontario
well first ride wasnt without problems it seems

when i pulled the plugs the front cylinder was milky white, compression was 190 rear and 210 front

pulled the head slight pitting on the pistons, too much compression

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so have swapped in some 40cc domes, compression is now a even 170 front and rear, will take it for a short ride tomorrow and check again to make sure all is good, for now im going to run the pistons, so wish me luck

double checked the timing curev.. the joins of having a programmable ignition!

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skis back together!

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Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
Careful. I ran a mix of avgas/pump gas at 200psi in my old 760 big bore and now the same mix in my 970 @ 185psi. And that was with a b-pipe. The pfp likely requires more octane.
 

steve-uk

Manners cost nothing
Location
Barrie - ontario
well seems the gods arent shining on me

heres a quick history lesson, when i got the motor i noticed the front cylinder was scored, i was told low hours on the motor, but that the guy had blown an oring, when i took the head off, i noticed the back pistion/dome had normal wash and the front had nothing

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so i had a chat with jetworks, they said they though it was a leak from the exhaust manifold

decided to have the pistion bored out to 84.5

all was good, test ride last week, pulled the plugs and the front was covered in cream....

also had 190psi in rear, 210 psi in front

when i pulled the head, id not intalled the two o-rings between the dome and head, my bad, so thinking this is the issue, i replaced the domes with 40cc, all new orings, compression test now read 170 psi front and rear so im happy

took the ski to the lake last night, pulled off the trailer and warmed it up for say 30-60 secs

stopped the ski, went to start it again and it wouldnt start... battery was dead

no problem, just sucks but theres always tomorrow

get it back, pull the plugs... same issue, cream all over the front piston, compression test, rear 170 psi, front now 190psi...so wtf

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with everything else going on i just dont have the time or energy to sort this out

i think maybe decking the cylinder will resolve the issue

but right now i have over $3500 into this short block, even if i try to sell it i have no idea what price point to put on it, some one who has more time than me could probably sort this out pretty easily

right now i need a ski i can ride then put away and ride again

very frustrated right now, i spend all winter helping other people out and leave my poop until the last minute and this is what i get for it
 
stick with it. it seems your 98% there.
although at this point, if you deck the cylinder, it could work great and good to go, or issue could persist and you're out the cash. So i guess i understand where you're at with the frustration.

couple years back i couldn't get a SN to run for crap. not having an oring head and using OEM gasket, i pushed pulling the head, when i did i found out the gasket was fried. after that a cooling line clog etc. sucked but it's finally good to go. give yourself a little time to detox from it then find you're next wind and jump to it!.
 

Proformance1

Liquid Insanity
Location
New York Crew
Straight edge and a feel er gauge to cyl deck, head shell and domes. Check for problems, look for clues, youre close keep looking.
 
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I may be wrong, but do I see silicone sealant of some sort on top of the cylinders in the pics with the head off? I have always been told on a head with o rings put nothing on but a little grease to keep the o ring in place. I have had o ring seals leak on me before because of using silicone, It did something to the rubber.

http://www.adaracing.com/pdf/ya701m.pdf
 
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steve-uk

Manners cost nothing
Location
Barrie - ontario
hey brian

with an ATP head you use grease to hold the orings in and then use rtv on the cylinder surfaces, so its the rtv you can see

also remember this happened after 60seconds of running the ski
 
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