Looking at different sled options and had a question. I've spend the past 7 years on a 600 121, and that has been fine for me in terms of power, but now I'm also looking at sleds with 136/137 tracks. How much difference does it make in terms of engine performance having to spin a longer track? The only 136 I've driven is a Vector, so not apples to apples compared to 2S 600.
Difference in power for a 121 vs 136
- Thread starter Hoosier
- Start date
snobuilder
Well-known member
your engine is powerful enough to spin the heck out of a 121 on newer powered sleds that are a min of 60hp anyways....power is not on issue these days...most sleds are 100+HP.....think of it this way ...a studded 121 will hook way better than ANY length longer track in any trail conditions other than 2 feet a powder..
srt20
Active member
Many many different variables in comparing this. Traction, attack angle, how tight the bends are in the track, etc. Many 136s are faster acceleration AND top speed. Attack angle and radius of bends sucks up more hp than weight.
From a pure weight standpoint, I doubt you will notice a difference.
From a pure weight standpoint, I doubt you will notice a difference.
I have 3 Doo 600 etec's; 2012 121, 15 137 Renegade X, and 16 129 MXZX, all studded. Lucky to be able to compare all 3, and the difference of the power to the track is not that noticeable. In fact I think (just my opinion) that the 137 spins less and grabs better, where the others tend to spin more. Ride quality is where the 137 works better, although it takes a little more work to throw it around and through the corners. 129 works well, and could be an option. Seems like the 121's are fading away. As for a 2 vs a 4, not going to go there, as everybody has a difference of opinion. I ride a ton of miles, like to ride hard, and like the lightweight feel so a 2 stroke is my choice.
Thanks. I figured it's kind of obvious but most people don't get to ride very similar sleds but with slightly different tracks back to back, so I thought I'd ask. I'm set on getting another 2 stroke for the next sled, just getting opinions on track length. Hoping to do some demo rides in March.
goofy600
Well-known member
In doo's case they change the gearing a little to compensate for longer track so your only losing a little on top end compared to a 121. Yes you will notice 121is a little more nimble than 137 but not worth the trade off of better ride and 137 way better if you get into fresh snow. Smaller people are about the only ones that i hear complain about the 137's pushing but still not bad. My wife really likes the 129 over her old 120 and better than my 137, I would think about switching to a 129 but I always lead our group and like the longer wider 137 if we are on fresh snow cover trails or on forest roads with some powder the longer track just handles it better.
Son has an 08 Vector (121) and until this year I rode an 07 Rage (136). The chassis are slightly different but have the same F/R suspensions, same HP, etc. I believe the Rage has slightly shorter gearing than the Vector. You really don't notice any difference in power or acceleration between the two. The Rage will usually pull the Vector on hardpack from a standing start as it has a little more track on the ground. If you accelerate from 30 or 40 they run neck and neck right up to the top end. The Rage does handle bumps a little better due to the longer track, and of course does not rotate as well as the Vector in tight corners.
The Vector is the last sled in our fleet with a 121 and the replacement will be a 136 or greater....mainly due to the better ride when it gets rough.
The Vector is the last sled in our fleet with a 121 and the replacement will be a 136 or greater....mainly due to the better ride when it gets rough.
I think any of the modern sleds handle the bumps just fine, so I'm not too worried about that. We kind of avoid the beaten path anyway. I was thinking more if a longer track would feel like a dog in the twisties - if it's harder to turn and if you need more engine to turn the track.
Hoosier: Maybe throw a leg over 121 & 128 & 136-7 see for youself. As others have said not many 121s left prolly never phase out for fans but 128 becoming shortie standard. Longer tracks don't seem doggie to me but left 121 behind in 2007 went to 136 & now on 144 an never will go back to less than 136. I had the same questions back in 2003 renegade or mxz bought the shortie then 2007 made the transition to 136 and not going back even to 128. Try it see if you have objections but don't think you will. 
G
G
Guest
I went back. 121s are lighter, they turn better and they are usually faster. However I don't ride 6 inch plus powder or rough trails. For the last two years there hasn't been such a thing as 6 inch powder where I ride so it hasn't been much of a problem. If the trails get rough screw it - off to the firelanes. Don't try to tell me that rough trails are great on a long tracker. Been there done that. Rough trails suck period.
C
Cirrus_Driver
Guest
Don't even bother with a long track unless you're into "off trail" deep snow. All that prattle about "better bridging" is pretty much overstated. For trail riding you will get tired of the handling on a 136. Tried it - I'll never ride anything but the shortest track available.
arctic600cat
New member
I have a f-7 ext 144 and love it!! I can run with new ski-poo 800. I will never go back to a short track. We ride mainly UP and when you jump off trail all of our 121 friends get stuck. You can run circles around them!!
Hoosier: Maybe throw a leg over 121 & 128 & 136-7 see for youself. As others have said not many 121s left prolly never phase out for fans but 128 becoming shortie standard. Longer tracks don't seem doggie to me but left 121 behind in 2007 went to 136 & now on 144 an never will go back to less than 136. I had the same questions back in 2003 renegade or mxz bought the shortie then 2007 made the transition to 136 and not going back even to 128. Try it see if you have objections but don't think you will.
That's a good idea - when we go up in March I'm going to try to find some demos to ride.
it is all in what u want.
are longer tracks faster? well how many drag sleds do u see with a 121?
u will loose a few mph on top end . but U will always get the hole shot and less slippage up to top speed. by the time a equal 121 catches up u are well past 1000ft and he will still not be much ahead in 1/2 mi prob ski tip to snow flap.
a 136 will push a bit more but I have never had a shorty pull away on any tight twist trail.
as far as 128 well racing results are what they are and most snow x and CC teams have converted
are longer tracks faster? well how many drag sleds do u see with a 121?
u will loose a few mph on top end . but U will always get the hole shot and less slippage up to top speed. by the time a equal 121 catches up u are well past 1000ft and he will still not be much ahead in 1/2 mi prob ski tip to snow flap.
a 136 will push a bit more but I have never had a shorty pull away on any tight twist trail.
as far as 128 well racing results are what they are and most snow x and CC teams have converted