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Jetting down procedure?
Posted: Sun May 06, 2012 9:01 am
by Madman
Ok getting close, got 55/138 and it's running smooth!! Just some more tweaking and I'll be sweet
Re: Jetting down procedure?
Posted: Sun May 06, 2012 9:38 am
by evilone
55/138 on a 21 oko is high. I ran that in a 28 oko on my 72cc setup.
Jetting down procedure?
Posted: Sun May 06, 2012 10:59 am
by Madman
Yeah I should mention I've changed to a 28mm
Jetting down procedure?
Posted: Sun May 06, 2012 11:52 pm
by Madman
So it happened SOFT SEIZE in pilot jet guess I gotta do a leek down test! And I need a CHT badly.
Re: Jetting down procedure?
Posted: Sun May 06, 2012 11:55 pm
by bakaracer
what are you mixing at? do you have a 55 pilot?
Jetting down procedure?
Posted: Mon May 07, 2012 2:32 am
by Madman
32:1 premix! Yes have 55 pilot!
Re: Jetting down procedure?
Posted: Mon May 07, 2012 2:43 am
by paulpauly7
check for airleaks around the cylinder,intake and case seals
Re: Jetting down procedure?
Posted: Mon May 07, 2012 10:22 am
by evilone
Madman wrote:So it happened SOFT SEIZE in pilot jet guess I gotta do a leek down test! And I need a CHT badly.
Same here. I've tried a 55 and 58 pilot with a 140 main and am soft seizing too.
Jetting down procedure?
Posted: Mon May 07, 2012 11:02 am
by Madman
evilone wrote:Madman wrote:So it happened SOFT SEIZE in pilot jet guess I gotta do a leek down test! And I need a CHT badly.
Same here. I've tried a 55 and 58 pilot with a 140 main and am soft seizing too.
It's a real bummer and I hope I haven't destroyed my bore! Still runs ok but I'm too scared to ride it until I get a cht and tear it down to search for a leak, if I have one!
Re: Jetting down procedure?
Posted: Mon May 07, 2012 11:46 am
by Mystic
If and when you do take it apart you can smooth out the piston skirts with a wire brush on a bench grinder if the scoring isnt too deep it should work just fine

some of these taiwan kits need the piston skirts chamfered so they dont scrap the oil off the cylinder walls and the ports chamfered so the rings dont catch
Re: Jetting down procedure?
Posted: Mon May 07, 2012 1:04 pm
by Madman
Mystic wrote:If and when you do take it apart you can smooth out the piston skirts with a wire brush on a bench grinder if the scoring isnt too deep it should work just fine

some of these taiwan kits need the piston skirts chamfered so they dont scrap the oil off the cylinder walls and the ports chamfered so the rings dont catch
check the damage on my other post Madman goes KABOOM
Re: Jetting down procedure?
Posted: Mon May 07, 2012 1:25 pm
by Bear45-70
Mystic wrote:If and when you do take it apart you can smooth out the piston skirts with a wire brush on a bench grinder if the scoring isnt too deep it should work just fine

some of these taiwan kits need the piston skirts chamfered so they dont scrap the oil off the cylinder walls and the ports chamfered so the rings dont catch
If you want to do it wrong, then this will work, maybe but it is not the correct way to go, EVER!
Re: Jetting down procedure?
Posted: Mon May 07, 2012 2:52 pm
by Mystic
If you want to hone the cylinder and get a new piston and rings then go for it but since you have the other brand new kit why not squeeze every bit out of the damaged one since you are going to junk it anyway right?? honing the cylinder and buffing the piston smooth where it seized will work

Jetting down procedure?
Posted: Mon May 07, 2012 6:24 pm
by Madman
Mystic wrote:If you want to hone the cylinder and get a new piston and rings then go for it but since you have the other brand new kit why not squeeze every bit out of the damaged one since you are going to junk it anyway right?? honing the cylinder and buffing the piston smooth where it seized will work

yes interesting idea the bike was still running when I pulled it apart and was not correctly tuned so it would give me chance to tune it more before I go and destroy another kit!
Re: Jetting down procedure?
Posted: Mon May 07, 2012 6:32 pm
by Mystic
It cant hurt

if you have a bench grinder it will be really easy. put one of those wire brushes on it and brush the piston skirts where it seized, not up and down but side to side then a light hone on the cylinder to get rid of any aluminum that stuck to it. also it wouldnt hurt to make sure that any edges are chamfered on the piston and the ports with a small file. The worst that can happen is you sieze the bore again. I have done this before so i know it will work. Just for giggles I took the stock bore and piston that came with my af16 when i got it that only had like 60 compression and would not start at all. Did what I described and replaced one of the broken rings and it cranked right up