Engine upgrade
If you want to performance the engine some more you are looking at P&P on the heads, new pistons, cams and all components chosen to get you to the right corrected compression as a system. You are also looking at a new, larger throttle body, roller rockers, higher performance tappets, adjustable pushrods, etc., then a re-tune.
Your bike is an '04, so it has not been stroked. You may think about taking the bottom end apart, installing the stroker crankshaft then you can achieve 103" or 107". While you have the bottom end apart do the timken LH main bearing mod.
So, all of that should add up to about $6K - $7K. Now you are in the neighborhood of a crate motor. How about a S&S 124"? That is why I asked how much do you want to spend.
Since you have all of that torn apart, let's go ahead and install the 6 speed tranny. Do you see what I mean - there is no end to what you can do. Oh yeah, we are going to need to address the clutch, too. While we are at, we should probably install an oil cooler.
Last edited by harley_jeff; Mar 4, 2012 at 10:51 AM.
So basically, you have three routes you can go; bore your cylinder to fit new pistons for 95" or 98" displacement, work the heads, new cams, valve train and re-tune. A combination of components that play well together and about $2500 later, you should be happy.
The second route is spending more money to go bigger, i.e., lower unit work; Lefty main bearing; new crank, trued, balanced and welded; new cylinders/pistons, headwork, cams, valve train, etc. and about $5-$6K later, you're done.
The third route is the crate motor route. H-D 120R is the best crate motor deal going now; some discount dealers are selling them for under $5000.
So, how much do you want to spend? IMHO, you can achieve your goal following through Door #1.
If it's a canned map I will bet some tuning will turn out a few extra hp and torque.
Remote tuning isn't perfect because each bike is different. My mustang ran a canned map from sct which equalled 266rwhp and 302ft/lbs torque.
I got it dynotuned and got 280 and 325 ft/lbs torque.
That is power you can feel. And cost me 3 hours dyno time.
Try a dyno tune unless you really want to throw money at it. The S&S 124 is a bad boy for sure
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