M
09 M8 P/G pushing 7.5 lbs, around 9000 ft last weekend in moderately heavy powder was turning 43 to 48 constantly, hit 50 to 51 occaisionaly.
Track speed gearing and clutching debate.
- Thread starter WyoBoy1000
- Start date
stock gearing for a M8 with a 162 is 74mph
I geared my CPC to 104mph works excellent
I geared my CPC to 104mph works excellent
Track Speed is King
As far as I can tell the track speed determines how much snow the machine moves and the more snow that is moved the better for climbing, sidehilling, deep powder and all the rest.
Also observed is that most all stock machines do not have enough clearance between the tunnel and the track which slows down the track because the snow is not able to pass through the limited space.
The turbo motors should have plenty of power to generate huge track speeds but based on the reported track speeds it this thread the sleds will need to have more clearance between the tunnel and the track to achieve outstanding track speed in the neighborhood of 70 to 100 mph.
Just my $.02
As far as I can tell the track speed determines how much snow the machine moves and the more snow that is moved the better for climbing, sidehilling, deep powder and all the rest.
Also observed is that most all stock machines do not have enough clearance between the tunnel and the track which slows down the track because the snow is not able to pass through the limited space.
The turbo motors should have plenty of power to generate huge track speeds but based on the reported track speeds it this thread the sleds will need to have more clearance between the tunnel and the track to achieve outstanding track speed in the neighborhood of 70 to 100 mph.
Just my $.02
I'm glad that opinion is yours, it makes no sense. How is the track going to pick up more snow than the lugs can handle. Also the PC is design specifically to no pull the snow through but pack it under the track. This thread has nothing to do with how far we go or whos got the most track speed, its just talk and food for thought as there are way to many variables. If track speed was king my piped m1000 would rock the TM8, and the TM8 stomps the m1000.
Last edited:
M
I agree. Too much track speed and not enough traction can result in less ground speed. Camo extreme time!
Yep, Just shootin the chit.:beer;:beer;:beer;
elevation 9000 (cooke city) 12 to 14 pounds of boost, 09 M-8 153 power claw, Cutler stage III burning 110 race fuel. track speed of 60 to 65 in dry pow, in wet heavy snow 50 to 55. i have found at times with a short track high track speed will work aginst you.
C
Did some playing today. Right on 6psi, tuned decent, new primary clutch due to spider rollers ****ting the bed, some rear suspension tweaks to work on the wheelie situation, was getting 48 most of the day, some spots 50. Pretty setup powder, but slow ground speed, letting it dig. Not sure what to attribute the mph gain, but I'm guessing a good working primary? Either way the sled was rippin today, sun was shining, and I was smiling!
It seems harder snow makes more speed
C
Definitely could be the case, I do make sure ground speed is slow when I'm checking. But there are so many variables that it's hard to know for sure.
looked this weekend, forgot to check before turning it up a bit, but..
11psi,
10,500-11,500 feet
3 gal AVgas 7-8 gal 91.
CF800 with 141PC
cutler stage II
I looked twice on small pulls in rather loose snow, first time down lower was 68 second time was 65 about 1000 feet higher. I didn't get a long look, so I may not be seeing some fluctuation, but two speeds that are pretty close I guess are worth reporting.
I'll have it as 13-14 psi next weekend, we'll see how that compares.
Keep in mind, it's a 141, I would HOPE I'd have way more track speed... I need it to keep up with a longer sled!
11psi,
10,500-11,500 feet
3 gal AVgas 7-8 gal 91.
CF800 with 141PC
cutler stage II
I looked twice on small pulls in rather loose snow, first time down lower was 68 second time was 65 about 1000 feet higher. I didn't get a long look, so I may not be seeing some fluctuation, but two speeds that are pretty close I guess are worth reporting.
I'll have it as 13-14 psi next weekend, we'll see how that compares.
Keep in mind, it's a 141, I would HOPE I'd have way more track speed... I need it to keep up with a longer sled!
S
I respectfully disagree. While there are MANY variables such as weight, approach angle, track length, suspension etc., track speed does make a BIG difference. Take identical M8 153s. Put a turbo on one. What makes this sled climb higher or stay on top of the snow better???? Track speed. More track speed results in the displacement of snow in the opposite direction in which the sled will travel. The inertia caused by the said displacement of snow is what propells the sled. Same as a mud buggy in the mud pit.
Not to start an argument, and no bash intended, but track speed IS paramount in keeping a sled on top and up over.:face-icon-small-hap
Sam
Y
I'd almost have to disagree with you. There seems to be something that doesn't make sense. I suppose it only common sense that your T1200 with 95 mph track speeed will beat something with 55 mph. But with the TM8 it doesn't make sense. More than once I've had someone agrue with me when they ask what the turbo makes for track speed. Mine pull 49-55 when working hard. I hear "my stock sled makes that". As everyone turboed knows, theres no comparison to a NA sled to the turbo.
I wish someone could explain why a stock M1000 with 50 mph track speed will get blown out by a TM8 with 50 mph track speed.
Maybe you should re read the thread, My piped m1000 makes more track speed (47mph) but my T-HCR (42mph) stomps the piss out of it. If the snow is shoved out to fast you will have nothing left get traction on, the design of the power claw is to pack the snow under the track and grab traction. Now if a track hooks up harder than another track it will also drop track speed. The only way you can judge track speed is to use the same sled, same day, everything the same and change something and get a different result, then you have something to speak of, But even if someone had a sled setup identical to mine you still could not say it was a perfect judge, maybe close but not comparable, there are just to many variable.
Now one more time, This thread is not about performance, or comparison, or what ever, its just out of curiosity to maybe understand different aspects of how these turbo'd sleds work. Don't argue with it just listen and think (don't over think it either).
Now one more time, This thread is not about performance, or comparison, or what ever, its just out of curiosity to maybe understand different aspects of how these turbo'd sleds work. Don't argue with it just listen and think (don't over think it either).
S
No overthinking. It's physics gents. What do you think is the force that propels the sled?? Now obviously this does not apply to a sled on hard pack. Only deep snow. The velocity of the snow that is "moved" in one direction, ie track speed, results in higher momentum the other direction. I have 2 M8s. Only difference, one has an OVS tial turbo. The other is NA. What causes the turboed sled with higher track speed to attain a high mark, or enable it to go much farther on a DEEP day? Track speed. The inertia created by snow that is propelled by the track is much higher, in turn creating a forward speed that is greater. This allows the sled to get on top of the snow instead of plowing through it. I HAVE done these comparisons. Same day. Same results. More track speed equates to a more effecient end result, HIGH MARK.:face-icon-small-hap
BTW, comparing the M1000 and the M8 is like comparing apples and oranges. I see your point, and I believe we may just be looking at things from a different perspective, possibly just arguing semantics. But bottom line, track speed IS very relevant when discussing a sleds performance ability.
Sam
BTW, comparing the M1000 and the M8 is like comparing apples and oranges. I see your point, and I believe we may just be looking at things from a different perspective, possibly just arguing semantics. But bottom line, track speed IS very relevant when discussing a sleds performance ability.
Sam
Last edited:
J
This is true given you are using the same length, height and design of tracks. Give me a 1" paddle and I will show you more track speed than you can shake a fist at but, it is not going to get me far.
As for my track speeds.
TM1000
9lbs boost on Av at 9000' in bottomless pow this weekend was turning low 60's.
J
A lot of this is true however if gearing was a fallacy we would be running no chain case or diamond drives.
The clutching you are referring to is in the clutching but, there are many more aspects to making those clutches even work. Mainly GEARING!
For fun pick the weakest sled you can find and stick the tallest gearing in it and see how it runs. Now change just the gearing one tooth lower and see how it runs. Keep trying and you will find what everyone that has ever tried really tuning clutches has found.....gearing has a huge impact on clutches. Wither it be by a gear reduction system(chain case, diamond drive, etc..) or size of drivers(7,8,9,10 tooth), they all have an impact on clutches.
Do you have a turbo sled or just arguing to learn something. The only reason for a gear case on big power sleds is to get the clutching off the ground. any sled running 1:1 gears you could eliminate the Gear case and attach it straight to the drive shaft (wouldn't that be cool, drop a bunch of weight and less rotating mass) that is If the drive shaft was high enough. I have seen people drop gears on m1000 and they think its the chit, but then I pull right with them or farther, but there belts might last longer. Your not going to pull overdrive gears in a M5 though, but trying to hit the perfect gear can only be done with perfect clutching and clutching has a far greater effect than gearing in these sleds. If you notice the AC sleds are all geared to hit the same speeds, the higher rpm sleds have lower gears and visa versa. To add the DD setup works on a load base performance, if you free it up with low gears to much it wont respond the same and you can loose performance of the shift.
Similar threads
