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bottlefed1
03-09-2011, 06:34 AM
I'm getting my 400 fixed and its getting a 12.5:1 piston and a stage 2 hotcam. I also have a powerbomb head pipe, powercore 4, amr coil. the air box lid is going to stay on.

I need help with jetting i read a chart that said a 416 should get a 170main jet and a 42 pilot would I be ok with that.
honda400ex2003
03-09-2011, 09:45 AM
id start about a 172, 3rd notch on the needle, 42 pilot, and 2.5 turns out on the f/a screw. the full header will add but the lid will subtract. so you might be pretty close with the 170 also. maybe even a 168 in there.

steve
CJM
03-09-2011, 09:45 AM
Please dont put a 12.5:1 piston in it unless you plan on running 110 octane or E85 all the time. The machine is air cooled and cannot handle the detonation generated by that compression.

You will also pull out head studs and blow headgaskets as well if its not jetted perfect.
bottlefed1
03-09-2011, 10:07 AM
Originally posted by CJM
Please dont put a 12.5:1 piston in it unless you plan on running 110 octane or E85 all the time. The machine is air cooled and cannot handle the detonation generated by that compression.

You will also pull out head studs and blow headgaskets as well if its not jetted perfect.

I dont mind running 110 all the time . Its not a race bike and doesnt get rode all the time. when i do ride it ,its usually flat out in a straight line .
honda400ex2003
03-09-2011, 10:14 AM
head studs would be the other main concern with 12.5 but im not jumping on that ship again.

steve
bottlefed1
03-09-2011, 10:25 AM
Originally posted by honda400ex2003
head studs would be the other main concern with 12.5 but im not jumping on that ship again.

steve

I took it to a local shop that gets alot of buisness. He said that i needed a new piston and he ordered it I had no idea what compression i needed. he ordered a 12.5:1 compression piston and he may have ordered head studs as well I never thought to ask. If he knows what he is doing, I dont understand why he would do something like add a high compression piston knowing that the outcome could possibly blow up the motor and loosing a new and future customers. unless he covered all ends, which would explain why my bill is up to $1666.
honda400ex2003
03-09-2011, 10:47 AM
just get a parts list from him when you pick it up. he should be jetting it for you for that price. :eek2: steve
bottlefed1
03-09-2011, 10:49 AM
Originally posted by honda400ex2003
just get a parts list from him when you pick it up. he should be jetting it for you for that price. :eek2: steve

Yea he said that he would going to put in new jets.