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Re: port timings

Posted: Sun Dec 14, 2014 7:21 pm
by Muppet
lower transfairs if ya can even if ya hav t shortn ya pot

Re: port timings

Posted: Sun Dec 14, 2014 9:10 pm
by tea5ive
by taking 3mm (with 1mm gasket so 2mm) off the bottom of the cylinder

raise exhaust by 4.8mm gets 170.29

raise trans by 1.2mm gets 125.07

clean bottom of inlet and a bit of a rub with sum emery tape on inlet side of the piston gets 145.09.

will take the cylinder to work and machine it down. hope i have done me sums right :lol:

Re: port timings

Posted: Sun Dec 14, 2014 9:37 pm
by eden
132 aint too high imo!
unless you intend to stroke it which would make them higher

Re: port timings

Posted: Sun Dec 14, 2014 9:55 pm
by tea5ive
eden wrote:132 aint too high imo!
unless you intend to stroke it which would make them higher
i will be using a 60/107 crank as this what i have to hand and a 42mm ancillotti which i want to use, with the standard li125s gear box with 16 or 17/46.

Re: port timings

Posted: Sun Dec 14, 2014 10:03 pm
by eden
so its132 with that crank?

Re: port timings

Posted: Sun Dec 14, 2014 11:02 pm
by tea5ive
eden wrote:so its132 with that crank?

yes, with nowt done but allowing for a 1mm base gasket.

Re: port timings

Posted: Mon Dec 15, 2014 12:00 am
by eden
just raise the exhaust port enough to give it some blowdown

Re: port timings

Posted: Mon Dec 15, 2014 12:08 am
by Adam_Winstone
^... true but it'll then come on to what rev range he wants to run it at and whether the exhaust will allow it to get to the revs at which the porting works, otherwise it will be constantly out of the powerband :(

Re: port timings

Posted: Mon Dec 15, 2014 12:12 am
by eden
did he say what exhaust he was using? I must admit I didn't read all of the 1st page of posts lol

Re: port timings

Posted: Mon Dec 15, 2014 1:23 pm
by tea5ive
eden wrote:did he say what exhaust he was using? I must admit I didn't read all of the 1st page of posts lol

ANCILLOTTI