04-15-2006, 09:48 PM #1
someone please help this is getting costly
i have gremlin i cant find i have a tripple piped 1200r im lost it use to run 77.5 mph at 7890 rpms i seized a piston last june fixed that had a cracked pipe in july that ruined my crank and piston put a new trued and welded crank and 3 pistons in it and a new pto pipe had a stock milled head that was 130 psi ski ran fine for a couple weeks than i was missing over 500 rpms liek the pipe was cracked again pressure tested them twice last year put it away for the winter this year put a new set of heads on it to raise the compression up to 150 no change put new advent cdi no change coils measure out right reeds are fine carbs are good crank is not twisted it pulls great like it should to 7320 then hits a wall at 7350 not breaking up turn the high speed in 1/4 turn no difference it is like thats all it should be running any help
04-15-2006, 10:32 PM #2
I was gonna post an intelligent repsonse but i just found myself staring at your avatar for about 30 mins...uhhhh.
04-15-2006, 10:40 PM #3
04-15-2006, 10:46 PM #4
maybe the PVs?
if gas, remove the springs
if electric, disconnect the power cable to the servo motor and manually rotate the valves open
04-15-2006, 10:55 PM #5
Im with Phil,tie the PV's open and run it.It will be a dog out of the hole.
04-16-2006, 12:48 AM #6
Check your pm. I'm up tonight.
What is your carbs and Jetting?
Has the engine been pressure tested?
Silly question...did you put the pv cables on the right sides of the pulley?
What is your fuel pressure?
Have the carb pumps been tested?
Did you increase cooling? If so, what is your head pressure?
When you rebuilt your crank, were the 3 pickups nice and square, or did they have ANY damage?
Do you have your plastic coupler cover in place? Are you running water socks?
04-16-2006, 06:29 AM #7
i am running stock p/v there opening ive ran it with them tied open ive check them they work properly the spark plugs look perfect no i havent pressure tested the motor i dont have a fuel pressure gauge no i didnt increase cooling i didnt rebuild the crank i bought a new yamaha crank then had it trued and welded yes i have a plastic coupler cover in place yes im running new water socks
04-16-2006, 07:05 AM #8
Iwould take the covers off the powervalves to make sure 1 or more have not had the pin come out, and are staying down.
Or ,do a compression check after disconecting the p.v motor with the valves down, and then manually open the valves and re do. There should be about 5-7psi difference between open and closed.
04-16-2006, 07:13 AM #9
i have wave eaters so the pins are still good did a compression check and its 150 on all 3
04-16-2006, 07:44 AM #10
Have you tried a comp check with the valves up AND down?
It has been known for the valves to crack on the stems
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