Trying to figure out which cam is going to be the best in my bike. I have a 2012 RGU with a Pro Race Stage 4 103. Heads, 259 cam, larger injectors, 58 mm throttle body, and most importantly 10.5-1 pistons. Here are the specs on both cams:

600 SM

Open Close Lift Duration Centerline TDC LSA Overlap
Intake 21 39 600 240 99 198 100.5 40
Exhaust 43 19 600 242 102 183

577

Open Close Lift Duration Centerline TDC LSA Overlap
Intake 20 46 577 246 103 196 104.5 38
Exhaust 50 18 577 248 106 171


I want a cam that comes in at around 2500 rpm and pulls to 6200 rpm. The Harley 259 cam sucks. Here are the 259 specs:

Open Close Lift Duration Centerline TDC LSA Overlap
Intake 19 47 579 246 182
Exhaust 58 12 579 250 155

 

I know in a 95 inch motor with Baisley Pro Stock Heads, 52 mm Throttle Body, 10.5:1 and the 600 cam, it was making about 100 ft/lbs at 2500 rpm. Your Throttle body may be a bit big for a 103 which could take a little away from the low end torque, but probably not much.

 

With what you have vested already into your scoot, I would pick out of the two choices the Tman 600 cam.


But that's just my opinion.


Good luck with you choice.



YB

 

I talked to TMan this afternoon actually. They recommended the new 577 cam. It seems to like the higher compression more than the 600SM. I guess thats the one I'll go with. It's a midrange upper end cam that is streetable. It has great low end torque as well with my setup.

He said it should solve my power issues. My bike was dyno'd at 106/106 when it was tuned. Kinda low for all the upgrades.

If you look on Tman's facebook page this cam pulls these 100/110 numbers with a stock engine, tuner, and exhaust. All I could say is wow when I talked to him.

 

If Your heads and valve springs can handle the lift you should also look at the tman 625 cam. Its the same cam as the tman 555 with more lift and it works great at 10.5 to 1

 

Yes I saw this cam and would love to have it. Unfortunately the HD Heads I have would definitely need work to accept this cam.

I had the HD 255 cam in my previous bike and it pulled like a freight train. I can only imagine how well the 625s pull.

 

You should just go with Tman's recommendation on the 577 cam because of your limited lift.

 

259e fine cam, you're exhaust is the problem, but it's you're money,you're bike.Lots running that stage 4 115/115 all day long with a 2/1/2 or 2/1 setup.

 

Go with what Tman recommends. He won't steer you wrong.