Speed Perception....

[NOS-PRO]

I'm glad the speedo is correct on the Vipers. My RX1's and Apex had to cut 2 teeth on the speedo gear to make it correct at 115mph.

But as mentioned....if a 600 flys past you or like TD mentioned.....slow is slow no matter how you look at it.

"Just need more power captain!"

 

[Zampinator]

If you want a fast & great riding Viper, go buy a 800rr Cat! Lol
I know, I used own one, & it's not even close on mid to top end. D&D can, clutch weights =120mph (165hp & 40lbs. lighter)

 

[fasteddie15x]

Just like everyone else I was disappointed last year with the top speed on my 2014 Viper LTX 137 track. So over the summer I decided I would do some mods on my sled. I went with the Ulmer trail package #4 and I also thought that this sled needed a gear change so now I have a 21 top 38 bottom for a 1.81 ratio. First trip of the year I could only see top speed of 96mph but my RPM seemed low, so I started adjusting the weights. With a few PM'S to NOS PRO about clutching, with his help I have seen 106 mph in perfect conditions and more consistent 95+mph on the trails. I do think the gearing change made about a 5mph difference I am even kicking around the idea of changing gears again to a 22 top 37 bottom for a 1.68 ratio to see if I can get even more top speed, but I also wonder if the sled has the HP to pull that gearing. I also tried ordering the COTC from pioneer about 4 weeks ago to try that, but they didn't have some of the parts in stock, so I never did get it. After seeing MR Sleds clutch testing I think I will just stick with what I have instead of spending the extra money.

Has anyone else besides me actually changed there gears, and if so what were your results?

 

[fasteddie15x]

Update on gearing. I just ordered a 37 bottom gear so 21 top 37 bottom for a 1.76 ratio. I will install it this weekend, but next trip won't be until Feb 23.

 

[tapex_07]

Update on gearing. I just ordered a 37 bottom gear so 21 top 37 bottom for a 1.76 ratio. I will install it this weekend, but next trip won't be until Feb 23.

Keep us posted.

 

[RTX]

Mr Sled.
I understand your logic and what you are getting at.
To be honest i dont need to go 100 mph i just need my sled to be competitive in the group i ride with.
When i purchased it new, it was not keeping up with the 2010 doo 1200 or the 2009 nytro i ride with. Both of these sleds are bone stock.
After 60-70 mph they would loose me on the trails.
After some clutch work and loosening the track it is running much better but i have not had a chance to really run it with my friends to see the difference.

Theres something wrong when so many guys cant break 85 mph stock but others are going 97-100 stock

 

[cannondale27]

RTX I dont believe they are. It does not count to do it one day on a perfect stretch like I did absolutely stock except for clutching. That does not make a 100mph sled. I want to see people looking for 110mph those people have 100mph sleds already. They are the ones that would be willing to put $100 on table saying they would do a hundred. Is no way I would do that even modded as I am now.

 

[SRXracer]

Remember this is the internet, and your mileage (or mph) may vary, literally. If someone is claiming a 100mph sled, you need to be wary of the conditions it was run in. Mine ran 103, on a plowed road, and the next day on a lake with a few inches of fresh snow it could hardly break 80 mph. It's all conditions. There is only so much power in these sleds, and they are setup to use it all from 0 to about 60 mph. I'm sure you could set it up to run higher speeds (gear up), but then you wouldn't have the snap and pull down low.

 

[MrSled]

Remember this is the internet, and your mileage (or mph) may vary, literally. If someone is claiming a 100mph sled, you need to be wary of the conditions it was run in. Mine ran 103, on a plowed road, and the next day on a lake with a few inches of fresh snow it could hardly break 80 mph. It's all conditions. There is only so much power in these sleds, and they are setup to use it all from 0 to about 60 mph. I'm sure you could set it up to run higher speeds (gear up), but then you wouldn't have the snap and pull down low.

Exactly.

 

[cannondale27]

Yes. So we need to find the MISSING power!

 

[Nytros rule]

If my sled is going to be a 150 KPH sled Im ok with that. What Im not ok with is 155 today 135 tomorrow 160 the next day in conditions that aren't that much different.
Im not ok with 20 or 30 KPH swings from day to day just because the temperature changed 5 deg. or a cloud blocked the sun or or or.

 

[Yamadog]

I can verify the speedometer is accurate. At teh Minocqua drags last weekend I ran 103 on the speedometer vs 101.83 on radar in 660 ft.

 

[DoktorC]

Yes. So we need to find the MISSING power!

Pipe, ecu or chassis...that's what is different from the Nytro (no one seems to complain about Nytro top end so..).

 

[kviper]

A couple thoughts! The same questions came up SOME when the 11 Apex came out. Pre 11 Apex was many times off by 15%, new Apex only a couple %. The difference with the Apex though is we have both Apex's to compare and found out the new ones are not slower. Conditions are HUGE! I have seen situation's running side by side with a friend with an identical sled, one pull the other then it would switch just because one sled picked up a stretch where the snow was set up from the night before and no sled's had run on it yet that day.
It is in stock form a 130ish HP sled with an accurate speedo!
The Turbo cat at 177 HP (in stock form) in same chasis doesn't MPH any better than a stock Apex at 150hp.

Many many many variables in snomobiling!!!!!!!

Also it takes HP to pull mph so with less HP in a chasis that's known to be not the most efficient condition variation will be more pronounced.

 

[Turtle]

Yes. So we need to find the MISSING power!

call arctic cat ... I'm sure they have it stashed away somewhere in a closet