i know the cam isnt designed for high compression but does it hurt to run it with 9.8 to 10.0 compression?

 

No, But a se 211 is very good for high comp.

 

It might. Your real goal is to keep the dynamic compression (AKA - effective cylinder pressure or cold cranking presure) less than 200. Preferably closer to 190. The three major factors in that equation are static compression, intake valve closing, and altitude. The 204 cam closes pretty quick, almost the same as stock. At, or near, sea level would place your pressures a bit on the high side for a street machine.

I live at 6,400' ASL, and often ride to 11,000' ASL. I rarely ride below 4,800' ASL. I used the 204 cam with 10.2 static compression. Most of the time I run on the low octane fuel; here in CO that means 85. When it's hot or under a big load I'll go up to mid grade; 87 octane. Engine runs great. But I expect if I ride to near sea level I'll be using premium.

There's very little performance to be gained by bumping yourpressure up over 200. Some, but not as much as you might think. And almost no low end torque. IMO, the trade off isn't worth it for a daily rider.

But, that's just my opinion. I could be wrong.

check the RBR racing web site for a dynamic compression calculater.

 

I ran the 203's in my 113" build ( was doing build in stages, already had the 203's installed because I had originally was going to do a 95" build.) It ran great and I had stock heads with work done the heads to get the proper compression-10.2 to 1. With this build I got 95 hp and 115 tq. Have since gone with HeadQuarters 575 cams, headwork and CP dishtop pistons, don't know what the dyno is, but sure is fun. Planning on doing my 03 wide glide next.

 

had the 204 cams in my 95ci with 9 4 to 1 comp. and had problems with pinging and starting. had the se ignition module. stock heads and vh big shots long . i didnt like that set up very well. dont do like me and do your engine build twice in one year. go on and get the good stuff first and you wont be dissapointed like i was .

 

I run this exact combo, except I use a SERT and my dealer did the heads.
My bike runs excellent, right from down low all the way up to 5K RPM. Plenty of torque everywhere and never any pre-ignition..
I think 99.9% will agree the 204 is probably the best all around cam in the SE line up. It's basically the exact same grind as the Andrews 37B with a 4 degree advance.

 

We have done several 96 inch engines with the 204 cams and ported heads along with 9.6-9.8 compression and have no issues. Head porting and tune are going to play a part. A local customer has this set up with 9.7 and his bike starts easy, no issues with ping at all.

To say no is blanket answer to say yes is the same. If you use it with a set of good ported heads, and have the bike tuned you will be fine. The bikes that we have provided parts for are at many different levels of elevation from sea level to 6000 feet. No issues on any of them. I posted the dyno sheet way back when we did the bike out of NY. 87 or 88 hp and 106 tq. No other mods than. Not bad for just swapping in heads and a cam. It is in the class of 26, 37 etc.

It would not be my first choice of cams but many times it is not up to us on cam choice. Tq wise the cam does ok hp wise well you could do better. The power is very usable and works well for a mild upgrade.

 

I've got to agree with dragosbikeworks. I left my EGC at 88" and added SE 9.5:1 pistons and the 211 cam. Dyno #'s are 82 HP and 85 lbs-ft. The 211 cam (with SERT) pulls very nicely through the mid range rpm's.

 

I just upgradded my 2006 Dyna Street Bob with the Screamn Eagle 95"
big bore kit and SE 204 cam. I am using the Power Commander III and
originally increased the percentages of the fuel mix. On the test
drive it seemed to be sluggish when giving it gas, and somewhere in
that ride the engine light came on. Although everything sounds good
(no pings / knocks) and both cylinders are firing nice. So I do not
think it is mechanical. Questions I have (1) why is it sluggish - I
though maybe flooding so I decreased the percentages and that seemed
to help a little (2) any idea why the engine light would come on
(running rich with 02 sensors???) (3) do I have to do anything to
reset the engine light or will it automatically go out when the
problem is resolved? Thanks for any help - ride safe
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I think a 204 and 9.5/1 compression would be just right. I run an Andrew TW21G with 9.3 compression with ported heads and larger valves. The intake closes at 30 degrees where the 204 closes at 34. Mine has over 100 ft.lbs. of torque down low where I ride. No pinging and smooth constant acceleration.