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Cast iron 225 factory tune 30phbh
Posted: Thu May 14, 2015 7:36 pm
by Markymark
Hi all,
Have the above fitted and porting cleaned up with a 30mm phbh with the following jetting
Pilot 53
40 slide
Av266
X7 needle
Main jet 126
My panel filter
After not running in properly (should know better)

had a seizure at 70 but have managed to salvage the piston and fit new rings with a view to running properly!
Interested in any other jetting combos you might have?
Re: Cast iron 225 factory tune 30phbh
Posted: Thu May 14, 2015 9:57 pm
by coaster
What does it run like with the current settings, have you done any plug chops?
Re: Cast iron 225 factory tune 30phbh
Posted: Fri May 15, 2015 7:17 am
by eden
main jet looks way too small to me
Re: Cast iron 225 factory tune 30phbh
Posted: Sun May 17, 2015 3:19 pm
by Markymark
Hi eden/coaster,
Apologies for the late reply,
Just got her back together and have changed to 55 pilot and 128 main but have yet to take her for a run.
Eden,
You mentioned the main being to small?
What do you think I should be running safety wise for the main? Have a af 9.5.1 head if that helps
Many thanks for your advice
Mark
Re: Cast iron 225 factory tune 30phbh
Posted: Sun May 17, 2015 3:48 pm
by eden
it is dependant on each motor but I would have thought 135 or bigger
it maybe that your atomiser /needle setting is too rich so your having to compensate with a smaller main jet!
jetting is a minefield if you don't have a good ear and feel for it
you can get the atomiser/needle closer by running with no main jet in, you also get a better idea of at what throttle position the main jets takes over from the needle/atomiser. Then start to dial in the main jet, starting BIG and coming down.
Re: Cast iron 225 factory tune 30phbh
Posted: Sun May 17, 2015 4:00 pm
by tavspeed
i have a similar set up to yours,but with a saigon/taffspeed copy,have just got a new 30mm phbh as couldnt get it to run without 4 stroking with a pwk
started with 55 pilot
av266
x13 needle 2nd clip from top
125 main
no air filter and 60mm crank
was very boggy from 1/4 to 3/4 throttle,so changed needle to a x7,runs nice and crisp,tried diffrent clip settings,but spark plug is grey/white
so went back to x13 with 120 main 2nd clip from top,runs nice but plug still looks grey,am i going in the right direction,should i try a 135 main with the x7 needle again at various clip positions
Re: Cast iron 225 factory tune 30phbh
Posted: Sun May 17, 2015 4:01 pm
by eden
try X13 on top clip with bigger main
Re: Cast iron 225 factory tune 30phbh
Posted: Sun May 17, 2015 4:03 pm
by eden
and remember it will be boggy when your fist set off until its warm, It can take over 5 miles to get up to temps, don't make the mistake of getting it just right as you leave home only to find it goes pop once you get on the open road at speed.
Re: Cast iron 225 factory tune 30phbh
Posted: Sun May 17, 2015 4:04 pm
by eden
also whats the timing set at and are the revs dropping off as they should? have you done a leak down test on the motor?
Re: Cast iron 225 factory tune 30phbh
Posted: Sun May 17, 2015 4:11 pm
by tavspeed
timing strobed at 16 deg btdc
had x13 on top clip with 125 main and 4 stroking after 1/4 throttle till main jet comes in
running a 60m crank , seems to have a lot of compression, squish is around 1.5mm