I have an 05 Mtn Viper with SLP pipes, 144 x 1 1/2" track - 23/40 gearing and 9 tooth drivers. It will pull to 9000 rpm then back down to 8800 (close as you can tell with factory tack.) It feels really good power wise but will not pull much for top end - about 80mph. The secondary is stock the primary has a W-W-W with 17.2 in and out. Should I see more top end or is this about all I will get - with that much weight should I gear to 21/40.
The plugs look good at 1/4, 1/2 and full runs but the DCS will flash randomly at 1/4 throttle long runs. I have 45 pilots, clips at 3.5 and 165 mains still vented to the air box. Should I go up one size on the pilots and try again or would octane boost be something to try - I only have access to regular 89 octane on most sled trips.
Sorry for the long post but I would appreciate some advice.
Thanks
The plugs look good at 1/4, 1/2 and full runs but the DCS will flash randomly at 1/4 throttle long runs. I have 45 pilots, clips at 3.5 and 165 mains still vented to the air box. Should I go up one size on the pilots and try again or would octane boost be something to try - I only have access to regular 89 octane on most sled trips.
Sorry for the long post but I would appreciate some advice.
Thanks
mod-it
Member
My '03 Mnt. Viper has a 144" x 2" track, gearing is stock. You must have changed the track to a 1-1/2 and put in the 9 tooth drivers? Or long tracked it from a short track? Mine has 8 tooth drivers (stock), can't find my gearing ratio (it is stock also). Anyway, I can only get 85 mph out of mine. I have thought about gearing mine down, as I think 85 is still a little to fast for a mnt. sled, all depends on what type of riding your wanting to do. For mnt. riding, most will tell you that anything over 80 is a waste. By gearing it down there is better track speed when hill climbing, assuming clutching is on.
Speaking of clutching, sounds like your rpm's are pretty close. Mine is reving to about 9100, than drops to 8900 when in deep powder or pointed up hill. Mine is set up exactly like SLP recommends, and I think it is working pretty good. I have all the SLP tuning paperwork if you need/want anything looked up.
Speaking of clutching, sounds like your rpm's are pretty close. Mine is reving to about 9100, than drops to 8900 when in deep powder or pointed up hill. Mine is set up exactly like SLP recommends, and I think it is working pretty good. I have all the SLP tuning paperwork if you need/want anything looked up.
I have changed the track and drivers - I don't ride much in the hills - would like a bit more top end for the trails.
Can anyone comment on the fuel/octane boost - will that help or should I put bigger pilots in.
you will need better gas then that no matter what jets you run, so I would add whatever you can to raise up the octane 89 is way to low for a sled.
mod-it
Member
mrviper700 said:
Definitely want higher octane. SLP suggests 91 minimum...
As far as gearing for more top end speed, Mrviper will have to help you there, he's forgotten more than I'll every know, lol.
Last edited:
Powder Trax
New member
Buy a bottle of octane boost if you only have 89 octane- (farm fuel-sorry couldnt resist it). Try Maxima Hi-Test Octane Boost - its what my Yamaha dealer sells and I use it in my quad and sled if my supreme fuel has been sitting for a bit.
My 2004MNT Viper has Simmons Pipes, Peak Heads, reeds and some motor mods. I'm overreving right now @ home but will put in heavier weights so I'll be bang on. My rpm should be 9100-9200. Jets are @ 160.0's across but I have an ATTAK installed. I only have rode the sled once as I just bought it in September. Running 156"x2" with 8t extroverts and 21/42 gearing. My buddy is the dealer here and said just a bit more tweaking and she will be dialed in. I am also using a Polaris primary with a Shockwave Secondary setup.
My 2004MNT Viper has Simmons Pipes, Peak Heads, reeds and some motor mods. I'm overreving right now @ home but will put in heavier weights so I'll be bang on. My rpm should be 9100-9200. Jets are @ 160.0's across but I have an ATTAK installed. I only have rode the sled once as I just bought it in September. Running 156"x2" with 8t extroverts and 21/42 gearing. My buddy is the dealer here and said just a bit more tweaking and she will be dialed in. I am also using a Polaris primary with a Shockwave Secondary setup.
I will try octane boost with regular fuel first - most of the time supreme is not avail in the small towns up North. (Your right the fuel in it now is right from the bulk station.)
..SNAKEBIT..
VIP Member
something is not right?
9000 RPM 23 top gear 40 bottom gear 9 tooth drivers = @112 mph
I have run 9000 19 41 9t = @ 88 mph
9000 RPM 23 top gear 40 bottom gear 9 tooth drivers = @112 mph
I have run 9000 19 41 9t = @ 88 mph
Sorry - Gearing in it now is 21/40 and I was wondering if I should go back to 23/40 - it holds the 9000 but seems to level out at 80mph - I was thinking lower gearing could free it up a bit and help with top end.
..SNAKEBIT..
VIP Member
THEN SHOULD BE 100-105
I would black marker the clutches to see if you are getting full shift?
I would black marker the clutches to see if you are getting full shift?
I thought a smaller top gear would give more top end. The sled would do 80 ish stock - I have changed gears to 21/40 from 23/40 and changed drivers from 8 tooth to 9 tooth. I have checked the primary but not the secondary - the belt is getting to within 1/4 inch of top on primary. I have the stock helix and spring (BLK/GRN) in the secondary for now but do have a new helix on order from Hartman. I will wait for that to come in and try it - if that does not work I will try changing the gearing back.
..SNAKEBIT..
VIP Member
Bigger Gear On Top - Bigger Top End
Crap - I think someone must have slipped me something. Original post was correct - I had 21/40 stock and went to 23/40 for more top end -