I got the 74cc Gilardoni kit for my Piston Port Derbi. It looks like it is going to be rad.
Buuttt... I either need to cut the skirt of the piston or I need to cut inside the case because right now, the back of the piston is hitting at the bottom of the stroke.
So, which one should I do? And how should I do it?
Not to be a dick, but you are in WAY WAY far over your head.
case. Buy a puller for the clutch, split the cases, and grind everything out. It isn't really very difficult.
case.. not the piston
Josh, what I should have said is that this build is going to be unlike every other engine build you have ever done. This is not a slap on and rock kit, it's not even a case match and rock kit.
Hit up the derbi dudes, Vic, Motomatic, and Cuperteens for guidance.
cuperteens have done this like 3 or 4 times i think.
cuperteens can suck my dick
Can you put the stock head on a gila with an extra gasket or something? Also whats the deal with derbi cranks, would that crank treats use to have work on a piston port? Is there any other source for performance cranks?
stock head won't work as the decompression channel would basically overlap/be way too close for a good seal. I think all of our bikes are using a metrakit derbi head (with decompression) and it works really well, much better squish and easier to start than the metra head.
We've got 2 of these built, and one currently in the works. Its not the hardest build ever, but its not bolt on and go.
I'm asking because I know that I don't know what I'm doing. I'm trying to learn. I have good competent friends here in Denver who are helping me but we haven't done this particular setup before. Please share your wisdom.
I just got the puller today and have everything off and am ready to split the cases. Once I grind that out, I think all I have to do for the kit to work is drill the stud holes to fit and possibly cut the fins. Am I correct?
Would any Puch head work?
yes and no. Don't relocate the studs, just widen the stud holes on the gilardoni. You only have to go out a few mm on each hole, much easier than re-drilling the studs into the case.
As far as heads, any puch head will theoretically work, but I'd strongly suggest getting one with decomp to make starting easier.
here is the difference in spacing. Some time with a dremmel/file, or a drill press will do this easy.
machine shop.. like.. 30 bucks.. it will be top notch...
1/2 hour with a hand drill and 7mm bit. Free.
Wire burn
anyone just try putting in helicoils with 6mm studs? then any puch kit would be bolt on right?
Ooooh good luck my friend!!! You'll make it work, I know you're such a perfectionist that it's gonna be awessssome!
no but I have seen the studs turned down in the center on a lathe kinda like motobecane studs.
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