Cams

[Syer]

I was just wondering if there was any dyno graphs where they tested all the different cams for the 450r.

duncan X11,X22 stage I, II hotcams and the HRC cam

Ive surfed the web and the forums and couldnt find any where all the test bikes were equal. Just wanted to find out what was wat before I started to build my motor

prolly looking at X22 or stage I, want low/mid

[WhiteZee]

you can get on www.trx450r.org and go to the performance faq and click on the cam thread, there is a lot of good info there.

[Syer]

Thanks from what they said it looks like I want a stage II

[WhiteZee]

np.

[dn1911]

stage 2 is an awsome cam for the everyday rider/racer. i love mine for the woods. you shouldn't be disapointed.

[DirtDevilBT]

Stage II or sparks cam. I bought my cam used so I didn't pay the "sparks" price. Damn good cam tho, barks and wants to go.

[Syer]

Alright so ive decided on the stage II and been reading about other mods.

So is it true you can run 92 pump gas with a 12.5:1 piston and stage II. How does this effect reliability, and is it a noticable difference over the 11.5 :1.

[Martin Blair]

I now GTT is runing 13.5:1 on 93 so i see no problem with it, just if your racing i would run mix as temps increase

[Syer]

Thanks alot.
This is my first attempt at building a motor. Im looking for a way to keep it 450cc and still whomp my buddies DS650. I do mostly trail rides and a few outlaw races (DNR, run boys run). I dont run balls out most of the time but if I do put it in the kitchen I dont really keep it there for long. Best way to evade is to keep it on all fours.
How is the reliability of a 12:1 and is it that much of an advantage over a 11.5:1?

[WhiteZee]

Originally posted by HN400exracer
I now GTT is runing 13.5:1 on 93 so i see no problem with it, just if your racing i would run mix as temps increase
hey, hold on there. just because a very experienced engine builder is running that combo does not mean the average person can. the camshaft plays a large part on which compression/fuel combo you can safely run. as far as i know, 12.5:1 and the stage 2 cam should be fine, but do not take my word for it. you should make a post on www.trx450r.org in the engine forum, you will get correct answers there.

[DirtDevilBT]

Originally posted by WhiteZee
hey, hold on there. just because a very experienced engine builder is running that combo does not mean the average person can. the camshaft plays a large part on which compression/fuel combo you can safely run. as far as i know, 12.5:1 and the stage 2 cam should be fine, but do not take my word for it. you should make a post on www.trx450r.org in the engine forum, you will get correct answers there.

Yeah I had always thought a 12:1 compression was as high as you ot to go safely on 91 octane. Like Zee said, it does have to do with cam overlap, duration, and compression bleed off as to what compression you really end up running on. I think I said that right? Correct me if I'm wrong.:p