top end help?

[ryan_larue]

I am new to this forum. I just blew up the top-end this sunday =/ First of all has anyone ever seen white speckles on your spark plug? im guessing thats bad since it doesnt run. i was gonna start racing a local circuit this winter but then this happened.

the guy that inspected my bike found sand inside my air filter and some sort of white speckles on my plug. he said im probably gonna have to get new rings, maybe a piston, and depending on the damage, the cylinder might have to be honed. if thats the case i might just bore it out and go with a bigger piston. any suggestions?

i have converted it to mix fuel.

 

[royalt67]

White specs could be aluminum. Are you sure it isn't silver?

You would have to hone it anyway if you get rings. Tear it down, inspect it, and get it measured.

And welcome to a new NW member!

 

[scotj77]

every time i had white specs it was melted piston

 

[royalt67]

Me too, I would expect to find aluminum smeared on the cylinder wall, pits in the piston head, or something like that. Only one way to tell....plus you gain a new paperweight.

 

[scotj77]

my blasty loves paperweights. it makes them faster than a chinese sweat shop any day

 

[royalt67]

my blasty loves paperweights. it makes them faster than a chinese sweat shop any day

That's the funniest thing I've read on here in weeks. (sorry, ryan)

 

[scotj77]

yeah man. seriously it sounds like it is prob a time for a piston and bore. i could be wrong but i doubt it.

 

[ryan_larue]

royalt67- it might have been silver. =/
thank you guys, this has helped
ok im gonna go with Wiseco for the piston and since it now has to be honed, im probably gonna bore and stroke it (since i just found a hot rods 4mm overstroke crank) so will a 2mm over bore be too much? what is the perfect combo to work with? ill have to keep the stock pipe on it for now until i can afford one

oh i forgot to mention that i have a set of boydsen reeds

 

[hudack]

dont bore it over anyunless it needs it and id go for a +3 instead of 4 because u gota get the cases trenched you should def send it to one of the builders on here ken,flotek,wildcard all great builders and get the cylinder matched to the crank to make the most power

 

[royalt67]

Chances are good you will need to bore it, but don't go any larger than you have to.That's a waste of a cylinder, plus there is no power to be gained by that small of an increase. Hudack is right tho, a +3 is alot easier to do. A +4 is cool but more machine work is involved. No matter what, if you are a noob to this, I wouldn't recommend putting in the crank yourself.

Pull it apart and get it to someone to measure it for you. Let them tell you what size to go up to, THEN buy parts.

 

[ryan_larue]

well the whole reason for the +4 crank was cause this guy on craigslist is willing to trade that crank for a used stock crank, if its gonna be too much work then ill just stick with the stock stroke.

 

[DirtDiggler]

welcome fellow N'Westerner !!!! yeah pull apart the top end first and see what's going on. Then if you want more get a big bore sleeve and have that installed , mind though you'll need a bigger carb , 30mm minimum , 34mm for some big flow. and a good pipe to open it up , plus port work yadda yadda yadda ....... remember , cubic centimeters has a direct connection to cubic dollars .

 

[ryan_larue]

and that is exactly whats holding me back from going all out on this ill just get the cylinder honed, the head polished and slap on a wiseco piston, i figured it was gonna be alot of money to bore it cause then id need a hotter ignition, bigger carb, new pipe, new sleeve, new reeds, yadda

 

[hudack]

and that is exactly whats holding me back from going all out on this ill just get the cylinder honed, the head polished and slap on a wiseco piston, i figured it was gonna be alot of money to bore it cause then id need a hotter ignition, bigger carb, new pipe, new sleeve, new reeds, yadda

wont need any of that for just a clean up bore kinda deal when we say bore it we mean to what t needs to clean the cylinder up
now for the big bore you dont need none of that but youd be a mad man not to get any of that it would hold back on the power so bad get it fixed and then get yourself a new pipe mabey an air filter jet it and you will be very happy with it

 

[ryan_larue]

and your absolutly right about that. as soon as i get my game plan set (the bore and piston combo) ill probably re-jet the carb since it will be off the motor. i just want to see this motor come alive, ive always been left behind on the dunes

 

[hudack]

and your absolutly right about that. as soon as i get my game plan set (the bore and piston combo) ill probably re-jet the carb since it will be off the motor. i just want to see this motor come alive, ive always been left behind on the dunes

you shouldnt have to rejet your carb just for the rebuild when you got to rejet your carb is when you get more flow in or out of the motor like air fliter exhaust port work stuff like that and leakdown test b4 you even start it after u get the topend rebuilt