06-28-2008, 02:26 PM #1
gp1200r running poorly. stock keyway question
i have a gp1460r and took it out today for its second try since building up the motor. it performed the same as my buddys 2002 fx140.. out of the hole the same, mid same, top end same... (althgouh i was only hitting 5500-6000 rpm) the speedo on his ski is actually very close (compared his to gps last yr) we were doing about 52ish. i did replace the pv motor it worked before i put it in the water but when i got back home the pv motor wasnt moving at all. i cleaned up the connection so that works now again. I want to go to the water and open the pv up and test the top end, but the bottom end is more important to me.
I was told that its likely my keyway but the keyway on my ski is stock. i did put an aftermarket lightweigth flywheel on it but didnt even know the keyway could make a diffrence so i didnt pay attention to how i installed it im starting to take out the motor but its 90 degrees outside and the ski is in diretct sunlight so i started to melt. i figured id throw up a post and get some response. the ski starts riught up and sounds fine. just very sluggish on the water
06-28-2008, 02:58 PM #2
I'd "STOP" with the taking the motor out for starters...!!!
If you're using a stock flywheel key..??
Then it can't make any difference to the timing..!!!
What ignition are you running..?? stock/advent/r&d/??..
Something is wrong..!! and its not the keyway thats for sure..!!
Can you list what mods are done..??
Have you checked your compression recently..??
Once again leave the motor where it is for now..!!!
06-28-2008, 03:14 PM #3
the motor is about 1 hour old.
ill check the compression out but i want to take the head off it looks like little burn marks on my pistons, all 3 look diffrent and all 3 plugs look diffrent. ill get pics up in a few
the crank was a new oem one( i believe it was oem ill have to see it might have been true'd and welded). lightweight flywheel. 1460 top end by kerry. he also did the head work and head gasket (stock heads) he did the powervalves (also stock) wave eater clips, riva filters, vf2 reeds, new pump with 14/20 dynafly. i have no idea what jets he put in the carbs but he did the carb work as well. d plate, free flow exhaust. was told i should be running about 77-78 mph
06-28-2008, 03:23 PM #4
Sounds like a fuel issue. Did you do a pressure test on the complete motor? A complete list of what you have would help be very detailed as every thing plays a role.
06-28-2008, 03:32 PM #5
purple (lightweight flywheel) jetnetics maybe?
vf 2 reeds
riva air filters with covers
1460 top end kerry hibdon ( kerry has been very helpful )
stock heads, and gasket.(milled by kerry)
stock pv's (milled by kerry)
wave eater clips
D plate with chip
free flow exhaust
new pump by Island Racing wiht 14/20 dynafly (i assemblied/greased)
riva 1200 intake grate
I just ran a compression test 130 on all 3 cylinders still warm. i opened the throttle to see if it makes any diffrence on the front cylinder and it didnt. it may be a fuel problem the primer has been giving me trouble, i primed the lines at the dock and the primer never got hard i couldnt find a leak but heard fuel coming out but didnt see any in the hull or smell any just assumed it was in the gas tank like an idiot.... im going to go look now possibly that? i still want to get you guys pictures of the pistons the middle one has a few marks on it like kinda like when you take your jumper cables and touch them together, those kinda marks the other 2 cylinders look diffrent
06-28-2008, 03:34 PM #6
also something else i noticed my front spark plug keeps having problems, first one cracked right down the middle of the ceramic white top part. second one looks as if the white part popped out and bent, and third one is bent also.... ILL get pictures. middle spark plug and rear one NO PROBLEMS atleast the top of it.
Also my powervalve motor keeps cycling now about every 10-15 seconds, with the lanyard out. and ski off
Last edited by spyder3000gtvr4; 06-28-2008 at 03:38 PM.
06-28-2008, 03:55 PM #7
If you have a bad primer it will cause the tank not to pressurize
resulting in a lean condition and bogging on top end like its
running out of gas. If it doesn't prime, take the primer off. If
you power valves are not working you will only see around
The spark plug thing is not good, keep a eye on it, and check the
squish clearance on that cylinder to make sure there not any
issues. Most of the time when you have a damage plug something
is coming in contact with it.
06-28-2008, 04:11 PM #8
I've seen people break the #1 spark plug during install. If your using a long extension the cowlings kinda gets in the way and may cause to much stress on the plug due to the angle. If its mechanical contact like Ben sugests it will get ugly quick. What does the ground strap look like?
To test the PVs just unplug the damn things. Remove the rubber boot at the top and physically turn the wheel all the way clockwise and test and then all they counter. You should have great top and no bottom one way and viseversa.
Stock carbs??? What jetting?
Take it easy on the new motor. I like to get at least 2-3 hours on it before hammering the crap out of it. Unless the pistons were set up really lose.
Where is the primer T at?? feed line or return?
06-28-2008, 04:16 PM #9
well heres some pictures, the 1 and 3 cylinder are spotless, the middle however is gunked up and the plug looks kinda fouled out. also the heads 1 is good and 3 looks a lil dirty but fine the middle is buit up a little bit. i dont think my primer is doing the right job i pumped it 3/4 times and i heard the splashing sound again then it got hard but i saw air in the primer line.
Since im doing the 1st tank breakin im running about 8.75 oz oil to every gallon. i tried getting pictures of the spark plugs but it didnt work. the #1 the white top piece is a little bent, the threads are a little greyish, the electrode is tan with some black on it, almost no build up. tip is black but clean. middle black gunk build up tan electrode, #3 tan electrode little black buildup, black tip clean.
06-28-2008, 04:23 PM #10
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