Questionya, u r right...but engine was built for and ran beautifully in fxr with different cam. nothing but trouble since i put in bagger, and i am stuck with it. if i change to lower comp pistons and change cam do ya think that will help ease spark knock. if so what comp ratio and cam would u reccomend
thanks for help.-------------------------
Followup To
Question -
johnny, whats up. i got an 97 flht. 97" engine, 10.5 to 1 pistons, crane .585 cam. heads have had some work done to em, dont know any numbers on em. thunderheader, se ignition and s&s super E carb and G (if needed).29.5 intermediate 76 main. champ rn12yc plugs showing rich.
what jet combo do u suggest.
i also have crane fireball ignition module which i have not installed yet.is this ignition better than se unit i currently have installed.
Answer -
I dont ever use Crane ignitions because they fail ALL THE TIME. I have replaced at least 150 of them in the last 2 years. I use only COMPU-FIRE ignitions. Your main jet is to big drop down to a 70. I dont really care at all for the engine parts you bought for your bike. They would not be what I would use. Combo is everything. Johnny 602-705-7474
Answerto change the compression is easy. Install thicker base and head gaskets. I go about .060" to .080" thicker combined. Get rid of the cam and install Bobby Woods W9B .630" nite prowler cam. and get rid of the thunderheader and install a white Brothers E-Series 2 into 1 header. This will make 10 horse power alone over the thunderheader with out the low to mid range drop. use a K&N air filter in the S&S, and NGK BPR8EA spark plugs gapped at .040" and torqued at 20 ft lbs also use the G carb not the E. Johnny
