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Cams.....

3017 Views 14 Replies 3 Participants Last post by  BBIII
lets talk cams.... I will be spraying my Vforce very soon. It is a 11.5 to one comp motor with ported heads and 36mm carbs. When I bought the bike, it had Fundy trail cams. They are great cams, not a huge lift, but decent duration....It's best pass in that set up was 4.6 something.... maybe 4.7. This was run by a friend at a race I was not at. Anyway, this past weekend I got a chance to try the local track with new Fundy race cams. These are high lift, not a lot of duration.... and I also added a drag pipe and a +10 swinger. Before I had a heck of a time launching with it's +4 swinger. Anyway, this is the 4rth or 5th time out and all it does is blow the tires off at the line, and not pull worth a darn down the track. it ran a few 5.teens.... at 59/60 mph with a best 60 foot of 1.88. Keep in mind this is with 25x12x9 16 paddle staggered extremes at 2 psi...

All that being said, I put my old trail cams back in to try them again this weekend. After talking to a few folks... it would seem that the race cams aren't ment for sand at all. I talked to another builder who agreed with me that it seems a nitrous cam needs to made with a bit more duration for the exhaust as opposed to the intake.. Any one else have any epxerience with this? I sure hope everyone isn't running just drop in stuff. I am comparing this to the stuff I went through with my cars...
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hey z nice to see you over hear too.

i would personally think the race cams would be fine but would need to be clutched and paddled different. normally when porting gets more aggresive and offers up less low end torque on my 2 smokes i lighten weights.

I am too wanting a nitrous cam thats why i hinted to glenn about that, any word from him?

maybe k&m will come along and shed some light on clutching big belt drives in a situation like this.
I tried a bunch of different weights. Started out with stock weights and a VFJ stage 4 clutch... and a lightened secondary. Went to a stock clutch, stock weights, stock secondary... no difference....added 56 grams weights... no change...

And yes, Glen is on the nitrous cam. Should have some results very soon.

Here is a vid of my bike on a dirt track with the race cams. It hauls rear off the line.... and falls right on its face...

http://s295.photobucket.com/albums/mm122/z...nt=HPIM4157.flv

here is an old vid with the trail cams... Sure looks a lot faster to me..

http://www.youtube.com/watch?v=Aoyc3uaOvWE&NR=1

http://www.youtube.com/watch?v=jd89jlartas...feature=related

I put the trail cams back in yesterday. Hope to have some results this weekend.
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here is a pic of my trail cams vs race cams....

http://www.kawieriders.com/forums/index.ph...st&id=24055
Which Cam is which?

the one on the right has alot less duration than the one on the left.
right is the race cams.... you saw how well they worked this weekend...
It didnt run to bad with the little thing on it.

the weights ok in the clutch pack?
tried all different weights, clutchs, been fooling with it since the last time you were in town... I would just sit there and blow the tires off with no top end.... that was never a problem before. My only issue before was keeping the front end down when launching....
Set it back to the way it was and start over.
I did, other than the weights... might mess with them tommorrow... if I need too... Don't want to spend to much time tuning as I plan on trying some other cams out in a few weeks...
Cool well let me know how it goes for ya.
so much better........
Blew a belt after about 4 passes.. broke the cvt cover.. and ripped a bolt out of the case... put my spare belt and clutch in... and rode the rest of the day.... Was holeshotting pretty much everything. A couple of my buddies 4 mill chettah supercub tiger paw shees would pull me top end by 4 to 5 bikes.... but they both run low 4's so.. that is about where I should be no juice and with a stock clutch in my bike... my god, , cams and a ride height change... what a difference.
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