AC 900's - what's your track speed

[2005 1m]

Trying to get some comparisons here for my own knowledge as I tinker with my clutching...

What tracks speeds & RPM's are you guys seeing in a long, steep & deep hill climb?

Please provide some info with your answer as well... track length, elevation, snow conditions (I'm most interested in feedback when it's REALLY light and deep). If you've gone to a big bore from the stock 900, please specify.

 

[diggerdown]

Stock 900 will get you 35mph on steep and deep. Anybody tells you they get 45 either weight 100 lbs. or don't know what steep and deep is. I've been down to 25 in heavy stuff and mine runs good. Oh, I go 260+, geared up start of the day.

 

[AdrenalineAddict]

It should pull 42MPH if your set-up properly.

 

[diggerdown]

It should pull 42MPH if your set-up properly.

So whats your secret to get that kind of track speed in steep heavy snow pulls? I've tried a lot of clutching combs and I can get my rpms to hold but not that kind of track speed unless I'm on less hill and snow.

 

[2005 1m]

my setup

Well I feel a little better about my setup now... I'm playing with it now and have a couple more tweaks that I think will help for the next time I'm out.

Right now I'm pulling 39-41 @ 7,400 to 7,500 RPM (held at that range) in true steep and deep at 10,000+ ft. 20/46 hyvo gears, straight 53 helix with steel red/white in secondary, titanium yellow/green in primary - trying some weight experiments, 0627-020 belt. I really think that there is more to be had though.

I go about 200lbs ready to ride and I've spent some time & money lightening up my sled - some hp mods as well.

 

[AdrenalineAddict]

For 10,000' spinning 40MPH in light snow is real decent. I had a friend with a 1M we played with a couple years ago, at 8,000' we could pull a steady 42MPH, can't remember the set-up it, forgot it a long time ago. We were seeing 42MPH with a 151".

 

[ak crash]

03 900 151, SLP pipe, can, and intake, Vforce 3's. The lowest I've seen is about 45 at about 7650(ish) rpm at around 2000'. Need to get this turd running right

 

[diggerdown]

Spinning a 151" track at 2000' elevation is a lot different than a 16 wide 162 at 10,000. Att20 tracks spin real fast no matter what elevation you're at but they don't hook up either. Lots of variables.

 

[2005 1m]

Well I feel a little better about my setup now... I'm playing with it now and have a couple more tweaks that I think will help for the next time I'm out.

Right now I'm pulling 39-41 @ 7,400 to 7,500 RPM (held at that range) in true steep and deep at 10,000+ ft. 20/46 hyvo gears, straight 53 helix with steel red/white in secondary, titanium yellow/green in primary - trying some weight experiments, 0627-020 belt. I really think that there is more to be had though.

I go about 200lbs ready to ride and I've spent some time & money lightening up my sled - some hp mods as well.

I just realized that I left out one major detail - my track is a 162" powerclaw. I really think that 44-45 mph is achievable. Engine mods are Vforce 3's, RKT mono high compression head, speedwerx Y & single, SLP can

Although these pictures were taken in flat areas, these came from the last two weekends when I was doing my testing... deep

 

[ccpowder]

I am running similar, except I run a 47* with a red/white in the 2nd softest hole. No idea on track speed cause I don't run a speedo, but I can tell you I give any normally aspirated sleds I ride with fits!! I run a Polaris Series IV 159" x 2.4" track.

The key to these sleds is to run a clutch setup that keeps the clutches and especially the belt cool. Vent the **** out of it as well. The performance drop is significant when they start to get hot.

 

[diggerdown]

I just realized that I left out one major detail - my track is a 162" powerclaw. I really think that 44-45 mph is achievable. Engine mods are Vforce 3's, RKT mono high compression head, speedwerx Y & single, SLP can

Although these pictures were taken in flat areas, these came from the last two weekends when I was doing my testing... deep

With the powerclaw you may be able to get that, they turn pretty easy. With the speedwerx pipe weren't you supposed to shoot for 76 -7700 rpm? Maybe drop a gram on the weights. I detoed my head and went back to factory until I can find a dome, definatly lost performance.

 

[Going West]

162 16 wide maverick. 5500 feet. Slp pipe, v force reeds, rkt head. 70 gram weights 49 helix with red white in middle hole. Rider weight 290 pounds with gear. About 42 mph falling to around 37 at the top just before turn out. Rpm 7600-7800. Sled runs extremely strong in deep fluffy snow, and alright on set up conditions.

 

[Joeschmoe]

162 16 wide maverick. 5500 feet. Slp pipe, v force reeds, rkt head. 70 gram weights 49 helix with red white in middle hole. Rider weight 290 pounds with gear. About 42 mph falling to around 37 at the top just before turn out. Rpm 7600-7800. Sled runs extremely strong in deep fluffy snow, and alright on set up conditions.

so what primary spring are you using in your setup?