hi guys! looking for some help on milling the stock exciter heads to use on the phazer cylinders.i seen were another person took them down to 72mm..this sled is being built to run 500 ft and wont be trail rode.so per say .040 gets taken off the heads-i need the 72 bore machined is that what they mean by reshaping? also how does this 485 exciter run? worth the work? thanks !
I'm not sure how your setup works, but reshaping the combustion chamber usually involves changing the squish angle on the head to avoid detonation. But I could be wrong, as I often am.
You should probably take a piece of solder shaped like an L long enough to stick down the plug hole and reach to the side of the cylinder paralell to the wrist pin, and rotate the crank to compress it. Measure it with a micrometer where it is flattened out. This will tell you how much squish you have between the head and piston.
You may want to consult MrViper over on the SRX site of this forum. I'm sure he can point you in the right direction.
Good Luck, John
You should probably take a piece of solder shaped like an L long enough to stick down the plug hole and reach to the side of the cylinder paralell to the wrist pin, and rotate the crank to compress it. Measure it with a micrometer where it is flattened out. This will tell you how much squish you have between the head and piston.
You may want to consult MrViper over on the SRX site of this forum. I'm sure he can point you in the right direction.
Good Luck, John
Appreciate the info john ...I will do some checking..there is a lot of good info on these forums..I am sure it helps alot of people!
Yamaha Nutz
New member
ok so what you are saying is you have had the EX440 cases bored to accept the phazer cylinders and are wanting to have the ex heads cut to match the cylinders ...........ok well the squish diameter of the heads should be 1mm larger than the bore ........meaning have them cut to 73mm and the squish band should maintain a 14 degree angle squish clearance should be not tighter than .035 on this set up best would be in the .040-.045 squish clearance .................
40-45 thousandths is pretty safe then? So first thing check squish with heads stock 2.cut "dish" in head to phazer bore? 3 recheck squish shave the head from there? Working with a guy that has small machine shop in garage.machine shops are limited around here just trying to make sure I am on the right page..thanks!