choie of cams RS 657 & T-man 650

[Skeeter]

Mike,</p>

What is the differecnce?between the cams RS 657 and the T-man 650?</p>

At 10:1 compression which do you like for the 107?</p>

Is the RS 657 to heavily laden towards torque for a light wieht weight bike like the Dyna FXDX and the set up we have been discussing?</p>

Is the T-man 650? a better blended cam? A better blance to torque?and HP. Is the T-man a narrow cam like the RS 657?</p>

Going to the T-man 650 &amp; bumping up the compression to 10:8 (10:8 I think it was where you said the cam works better) What does this do as far as making the motor?more diffcult?to start and the use to pump gas??</p>

I have a concern about bumping up the compression is this a valid concern for a hi way bike?</p>

[Mike]

Specs for each follows;
TM650 intake 26/52, 258 duration, exhaust 56/24, 260 dur, 104.5 LSA with corrected pressure @10.0=8.64
RS657 27/45, 252 , 53/27, 260 101 =8.98
The Red Shift looks better from a pressure stand point at 10.0:1 but would be better at 10.3-10.5. The TM cam likes about .3 more compression to achieve the same pressures (10.8) and has an LSA 3.5 degrees wider than the RS. The RS would produce more torque, all things equal. A lighter bike can normally stand a cam tending to HP. The 10.8 compr. will run hotter and could be an issue in very warm climes as yours and requires 91 oct fuel minimum. This additional heat can reduce engine life with increased risk of detonation. The lower comp. will start easier, less problem when good gas is unavailable, run cooler on long trips but make less torque and peak HP (it's alway a trade-off).
I would go with the RS 657, 10.0 with no worries. Regards, Mike

[Skeeter]

Mike,</p>

Thanks for the detailed answer.</p>

I think the 10.0 no worries aproach will be best.??Considering the hot summers and usually the grade of octane is only 90 in most places around here. Sure don`t want any detonation.</p>

Thanks, Skeeter?</p>