Custom/Hybrid Spark plug problem. BB760. HELPPP!!!

[superjetkev]

it seems fine? ive run 3 tanks thru it since i tore the engine down and replaced the last set of plugs. thing that gets me is i ran thos motor almost 2 whole seasons, had crank rebilt and cyl resleeved this spring. in 11 hours run time, ive broke 3 plugs all on the front cyl. msd boots too fwiw. no signs of deto, 94 octane and 170 psi. i still think bad plugs. in my 20 years around skis ive never seen it happen once, let alone 3 times. all plugs from the same box off ebay too fwiw

 

[fast superjet chase]

Check the squish seams to me it's to tight and causing a harmonic in the motor which is breaking the plugs. had the same thing happen to me. went to a bigger dome for more squish and it is fine now.

 

[SmittySX]

Maybe i should change to msd boots too..?

I just dont understand why this would have JUST started happening?

Im going to try and check squish, if i can figure it out.

 

[SmittySX]

Just got back from a short ride.. So what i did was opened the high speed screws on the carbs 1/4 turn to richen the mixture and i changed to high performnce plugs, BR8EG's. It ran great UNTIL it reached its peak of how hot the motor is supposed to get and it started bogging a bit... There was that white crap coming off of the front plug, BUT not too much.. The plugs were deffinately reading differently... It was like the front was just too hot and dry.
So i switched the plugs back to a BR8ES and rode for literaly 3 minutes and the front plug rattled loose...

So thats where im at.... ughhhhhhhh!!!

 

[Seanc]

40 people have told you to check the squish... Have you? I would put lots of money on that. Or a damaged dome

 

[ls1corik]

Hey im new here but ive had this happen before with banshees, and from what i remember it was either a lean condition or detonation i cant remember...

 

[SmittySX]

Well im about 99.9999% sure it WAS i squish problem..... Congrats to those who called it..... Anyone have hookups on dasa motors???

 

[motozachl]

Sorry motor blew dude but didn't know lots of people already suggested the checking the squish

 

[g-ski]

Sorry as can be but, the past is the past; put a motor in it and save the summer. Lot of ride time left. Still a stylin ski.

 

[SmittySX]

A lot of people said a lot of things... But your right Gordan, gotta rip apart the raider and drop the 701 in and go!! ... For now