WYo, I wonder how much of the difference you mention in speed is due to the 90 duro on the HCR compared to the 80 on your 1000?
Track speed gearing and clutching debate.
- Thread starter WyoBoy1000
- Start date
mynewuseddoo, If you mark your clutching you have to be very careful to get readings, ie if you pull a wheelie or cross a track you can wind up with a jump in speed. If you want to know your speed at a 1:1 you just as well mark them and run it on a jack stand. But as for track speed that has to be done on the hill.
JSCC, thanks for the info, But you say planetary then you say gears, I want to know the gear ratio, from the secondary to the drivers if the DD has 60/60 gears in it.
If you figure the mph by going from the center of the crank to 8" across the primary, (nothing else, just figured for reference) it would be like gearing up 2.4:1 Now I just want to know what speed you would be at hypothetically if everything was perfect with 60/60 gears and in a 1:1 ratio in the clutching.
JSCC, thanks for the info, But you say planetary then you say gears, I want to know the gear ratio, from the secondary to the drivers if the DD has 60/60 gears in it.
If you figure the mph by going from the center of the crank to 8" across the primary, (nothing else, just figured for reference) it would be like gearing up 2.4:1 Now I just want to know what speed you would be at hypothetically if everything was perfect with 60/60 gears and in a 1:1 ratio in the clutching.
My m1000 is lower than most also.
M
mynewuseddoo
Well-known member
Good call Wyo, thanks.
Good thread. Lots of interesting reading.
Here is my 2 cents about the gearing.
Clutching may need to be changed with gearing. You might change your belt height in your clutches at a particular point (such as that 40 MPH track speed in deep snow climbing a hill) and you may drop out of were you need to be. This is probably why you see mixed results when gearing down. Might pull the belt into the right spot with one spring setup and pull it out of the right spot with a different spring rate.
I would definitely think gearing would have a minimal effect on a turbo sled in comparison to naturally aspirated. I think taller gearing with boost would tend to load the motor harder and probably make more power.
This is similar to diesel trucks that usually make more power and boost in OD then in direct drive.
So I would think the stock M1000 gearing would probably work better with boost then M8 gearing because your carrying way more speed and pulling the belt closer to full shiftout then a naturally aspirated M8 ever will in deep snow.
Here is my 2 cents about the gearing.
Clutching may need to be changed with gearing. You might change your belt height in your clutches at a particular point (such as that 40 MPH track speed in deep snow climbing a hill) and you may drop out of were you need to be. This is probably why you see mixed results when gearing down. Might pull the belt into the right spot with one spring setup and pull it out of the right spot with a different spring rate.
I would definitely think gearing would have a minimal effect on a turbo sled in comparison to naturally aspirated. I think taller gearing with boost would tend to load the motor harder and probably make more power.
This is similar to diesel trucks that usually make more power and boost in OD then in direct drive.
So I would think the stock M1000 gearing would probably work better with boost then M8 gearing because your carrying way more speed and pulling the belt closer to full shiftout then a naturally aspirated M8 ever will in deep snow.
J
Jeff K
Well-known member
1 elevation 6-8000ft
2 lbs of boost 6lbs
3 what sled 09 M8 153
4 who's kit Cutler Stage 2
5 gearing 54/66
Speed around 55mph (deep heavy snow). For comparison, a stock 09 M1000 153 on the same hill was running 42mph track speed.
I lowered my gearing to 54/66 with a BDX diamond lite drive shortly after my turbo install last year and noticed a gain in track speed, as seen in the data above. I chose to lower the gearing for multiple reasons:
1. Lower gearing loads the engine more, which will help build boost. By lowering the geairng, the secondary is more sensitive to load which will make it shift out faster putting more load on the engine.
2. Lower gearing generally helps increase belt life
3. The M-Series sleds have always been geared too high IMO. If you ever see comparisons of the different sleds back to back, the M8 will lose the acceleration test every time, but always seems to win in top speed. For me, a mountain sled does not need to be geared to run 95mph+, unless I have the power to turn the track at 80mph in a climb.
4. The sled is WAY more fun to ride!
Clutches loose efficiency fast as they shift from a 1:1 ratio (belt has same diameter in both primary and secondary) into overdrive (belt has larger diameter in primary and smaller diameter in secondary) so the idea is to gear so that you are in the 1:1 range to ensure you are putting the maximum power to the track.
Here is a good book to read about clutching and gearing theory:
http://www.scribd.com/doc/30484148/Clutch-Tuning-Handbook
After reading the book, by my calculations the 1:1 ratio for 54/66 is 66mph, for 57/63 is 73mph and for 60/60 is 80mph (All assuming an M8 running 8000 rpm).
Clutching and gearing go hand in hand. Just changing the gearing on a sled may not always work out if the clutching is not setup to work with the new gears. By lowering the gearing, you need a quality secondary clutching setup. In my case, Cutler supplied their torsional conversion setup with the turbo kit which works fantastic.
Mynewuseddoo, I have a spare DD with 60/60 gears in it from a buddy's sled I can bring out in march if you want to that gearing as well
2 lbs of boost 6lbs
3 what sled 09 M8 153
4 who's kit Cutler Stage 2
5 gearing 54/66
Speed around 55mph (deep heavy snow). For comparison, a stock 09 M1000 153 on the same hill was running 42mph track speed.
I lowered my gearing to 54/66 with a BDX diamond lite drive shortly after my turbo install last year and noticed a gain in track speed, as seen in the data above. I chose to lower the gearing for multiple reasons:
1. Lower gearing loads the engine more, which will help build boost. By lowering the geairng, the secondary is more sensitive to load which will make it shift out faster putting more load on the engine.
2. Lower gearing generally helps increase belt life
3. The M-Series sleds have always been geared too high IMO. If you ever see comparisons of the different sleds back to back, the M8 will lose the acceleration test every time, but always seems to win in top speed. For me, a mountain sled does not need to be geared to run 95mph+, unless I have the power to turn the track at 80mph in a climb.
4. The sled is WAY more fun to ride!
Clutches loose efficiency fast as they shift from a 1:1 ratio (belt has same diameter in both primary and secondary) into overdrive (belt has larger diameter in primary and smaller diameter in secondary) so the idea is to gear so that you are in the 1:1 range to ensure you are putting the maximum power to the track.
Here is a good book to read about clutching and gearing theory:
http://www.scribd.com/doc/30484148/Clutch-Tuning-Handbook
After reading the book, by my calculations the 1:1 ratio for 54/66 is 66mph, for 57/63 is 73mph and for 60/60 is 80mph (All assuming an M8 running 8000 rpm).
Clutching and gearing go hand in hand. Just changing the gearing on a sled may not always work out if the clutching is not setup to work with the new gears. By lowering the gearing, you need a quality secondary clutching setup. In my case, Cutler supplied their torsional conversion setup with the turbo kit which works fantastic.
Mynewuseddoo, I have a spare DD with 60/60 gears in it from a buddy's sled I can bring out in march if you want to that gearing as well
M
mynewuseddoo
Well-known member
Ha ha, no I'm good on the 60/60 gears but thanks anyway. My belts will thank you for leaving it at home lol.
That's a good write up and it makes sense to me. Why run taller gears if the sled will never see those speeds in a climb? It makes more sense to lower the gearing to closer match the speeds in which the sled operates. Like you said, if 1:1 will have the track spinning at 73mph with 57/63 gears then I must be way off the 1:1 ratio if I'm only seeing 48 mph. The 54/66 will bring me closer to this ratio.
The Cutler torsional secondary should be a snap to tune to the new gear set. I think I'm running 4 or 5 right now with the green spring. I think that if I do need to change the secondary setting, it will only be by one hole.
Are you still running the powerclaw track Jeff?
That's a good write up and it makes sense to me. Why run taller gears if the sled will never see those speeds in a climb? It makes more sense to lower the gearing to closer match the speeds in which the sled operates. Like you said, if 1:1 will have the track spinning at 73mph with 57/63 gears then I must be way off the 1:1 ratio if I'm only seeing 48 mph. The 54/66 will bring me closer to this ratio.
The Cutler torsional secondary should be a snap to tune to the new gear set. I think I'm running 4 or 5 right now with the green spring. I think that if I do need to change the secondary setting, it will only be by one hole.
Are you still running the powerclaw track Jeff?
First off no one has verified what a 1:1 is, we have to know every gear ratio throughout the drive train. then factor the gears in. What I have stated was hypothetical. JeffK you say on 6lbs your getting 55mph, everyone else in that range says 40-50, thats to big of increase to compare so either conditions where different or something. Please explain. Do you pack extra weight like gas or what ever and what is your weight.
1:1 ratio is the point at which the belt is going around at the same diameter in the front clutch and the back clutch. Shooting for maximum percentage transfer of power from engine to the track , if the belt is not slipping, is at the 1: 1 ratio, and clutch efficiency drops off either side of the 1:1.
If you can adjust gearing to have 1:1 ratio in that range of maximum track speed on the course you are climbing, then you're going to have a pretty good running sled.
Track racers play gearing change sometimes hourly as track conditions change, most guys recreational riding just don't bother.
Higher gearing loads/increases the torque resistance that your secondary clutch senses.
A bigger longer track does the same thing.
Heavy wet snow does the same thing.
Tigher spring tension does the same thing.l
Riding your brake or a tight track can do the same thing.
So more resistance in the secondary makes your primary work harder to pull the belt down into the secondary, the primary clutch has to increase more RPM so the weights can push harder. So higher gearing more rpm in the primary.
A ligher low hp sled can handle higher gearing. A heavy sled with more hp needs lower gearing. Why, because of the limitations of the abliltiy of the same clutch's and belts to efficienctly transfer hp by rubber sticking to aluminum.
That does not always happen when the garage mechanic changes gearing because if the clutching before gearing change is a poor combination of clutching components or defective or dirty or testing takes place in unsimilar snow conditons, the observed results could be any thing.
When testing clutching components on the same hill the past 25 years, a gps recording ground speed is the best test gauge I have found.
Track speed is a valid performance gauge when all other variables are a constant.
If you can adjust gearing to have 1:1 ratio in that range of maximum track speed on the course you are climbing, then you're going to have a pretty good running sled.
Track racers play gearing change sometimes hourly as track conditions change, most guys recreational riding just don't bother.
Higher gearing loads/increases the torque resistance that your secondary clutch senses.
A bigger longer track does the same thing.
Heavy wet snow does the same thing.
Tigher spring tension does the same thing.l
Riding your brake or a tight track can do the same thing.
So more resistance in the secondary makes your primary work harder to pull the belt down into the secondary, the primary clutch has to increase more RPM so the weights can push harder. So higher gearing more rpm in the primary.
A ligher low hp sled can handle higher gearing. A heavy sled with more hp needs lower gearing. Why, because of the limitations of the abliltiy of the same clutch's and belts to efficienctly transfer hp by rubber sticking to aluminum.
That does not always happen when the garage mechanic changes gearing because if the clutching before gearing change is a poor combination of clutching components or defective or dirty or testing takes place in unsimilar snow conditons, the observed results could be any thing.
When testing clutching components on the same hill the past 25 years, a gps recording ground speed is the best test gauge I have found.
Track speed is a valid performance gauge when all other variables are a constant.
J
Jeff K
Well-known member
I weigh 220lbs and have the track rack gas cans always full. Like I stated above, when I was checking my track speed I was riding with a buddy that had a stock 2009 M1000 153 who was getting 42mph on the same hill, same conditions. We are pretty close in size. IMO, the difference can be directly attributed to lower gearing and a quality clutching setup.
From the book I referenced in my other post above, there is a calculation that can be quite useful:
MPH = [RPM x Driver Diameter] / [Drive Ratio x Gear Ratio X 336]
Driver Diameter = [# of Teeth x Pitch] / [3.14]
In our case, Driver Diameter = 8 x 3.0 / 3.14 = 7.64"
Drive Ratio = typically 0.75 - 4, but for this example: 1
Gear Ratio (Diamond Drive) = [Output Gear / Input Gear] x 2.24
The planetary gear had a built in gear reduction of 2.24
54/66 = 2.74
55/65 = 2.65 (Stock 2010+ M8)
57/63 = 2.48 (Stock 2007-09 M8)
60/60 = 2.24 (Stock 2007+ M1000)
In our case, Driver Diameter = 8 x 3.0 / 3.14 = 7.64"
Drive Ratio = typically 0.75 - 4, but for this example: 1
Gear Ratio (Diamond Drive) = [Output Gear / Input Gear] x 2.24
The planetary gear had a built in gear reduction of 2.24
54/66 = 2.74
55/65 = 2.65 (Stock 2010+ M8)
57/63 = 2.48 (Stock 2007-09 M8)
60/60 = 2.24 (Stock 2007+ M1000)
By looking at the calculation, it doesn't matter what 1:1 really is, it all works itself out. All we need to know is that we want to find the desired MPH for the ratio 1:1.
A
aktreekiller
Well-known member
hey
09 Hcr
Slp kit
48/36 helix
shift assist
rock rollers
75 cat weights
Keep Belt deflection spot on
0-5000 elevation
Track Speed= Butt Dyno verified track speed of, damn this thing pulls hard.
09 Hcr
Slp kit
48/36 helix
shift assist
rock rollers
75 cat weights
Keep Belt deflection spot on
0-5000 elevation
Track Speed= Butt Dyno verified track speed of, damn this thing pulls hard.
In our case, Driver Diameter = 8 x 3.0 / 3.14 = 7.64"
That doesn't make any sense
The best I can come up with is the sled is geared up in the clutches by 2.4 then dropped in the planitary 2.24 so there is still a gear up of .16 , with 60/60 gears. Thus 8000 rpm in a 1:1 with 60/60 = 92.8mph. 57/63 = 84.4mph. Now that just doesn't seem right. Thinking its going to be easier to put on a stand, mark the clutches and check for a 1:1 and see what the speedo says??? Personally I think gears can effect backshift but overall track speed can be accomplished with clutching no matter the gears.
That doesn't make any sense
The best I can come up with is the sled is geared up in the clutches by 2.4 then dropped in the planitary 2.24 so there is still a gear up of .16 , with 60/60 gears. Thus 8000 rpm in a 1:1 with 60/60 = 92.8mph. 57/63 = 84.4mph. Now that just doesn't seem right. Thinking its going to be easier to put on a stand, mark the clutches and check for a 1:1 and see what the speedo says??? Personally I think gears can effect backshift but overall track speed can be accomplished with clutching no matter the gears.
J
Jeff K
Well-known member
Then measure the driver diameter for us. That is the formula to calculate it, but I am nowhere near me sled to measure mine to back it up.
1:1 means that the belt in the primary and the secondary are running at the exact same diameter in both clutches. This means that both the engine and secondary are spinning at the same RPM. From there, the gear reduction of the Diamond Drive and the diameter of the drivers determine the track speed. When the clutches are in a 1:1 ratio, they are turning at the same speed.(Think of a truck driving in a 1:1 transmission gear. The Engine and Transmission are spinning at the same speed, but the gear reduction in the rear end and tire size determines the vehicle speed.)
Also remember that we are talking about an M8 in this case running at ~8000rpm. If you are going to calculate the speed of an M1000, you would use ~7400rpm.
Dam, could someone explain what a 1:1 is again.
Jeff you seem to know something and I am not calling you a fool, but chit who many times do I have to say it.
WTF is the actual speed when the clutching is in a 1:1. NOT PLEASE EXPLAIN A 1:1 again. Then again don't bother. I doubt I will believe it if someone tells me after all this bs. Kinda why I said track speed really doesn't mean anything when its not done in a controlled test.
Thanks for some of the info, some of it is good to know
started another thread hoping to stay out of this
http://www.snowestonline.com/forum/showthread.php?p=2614659#post2614659
Jeff you seem to know something and I am not calling you a fool, but chit who many times do I have to say it.
WTF is the actual speed when the clutching is in a 1:1. NOT PLEASE EXPLAIN A 1:1 again. Then again don't bother. I doubt I will believe it if someone tells me after all this bs. Kinda why I said track speed really doesn't mean anything when its not done in a controlled test.
Thanks for some of the info, some of it is good to know
started another thread hoping to stay out of this
http://www.snowestonline.com/forum/showthread.php?p=2614659#post2614659
Thats what everyone assumes, but I think it is off. Like I was saying weather you factor the gear up in the clutch or the driver it goes up 2.4 then down 2.24 in the planetary.
Jeff you ever come up to cooke, I would like to see that sled run. It sound impressive.
Jeff you ever come up to cooke, I would like to see that sled run. It sound impressive.
J
Jeff K
Well-known member
I've never been to Cooke, but hope to one day. If I do, I will let you know
Please explain this 2.4 number you keep mentioning. You have lost me there.
go 8" across the clutch where you would get the 1:1, if you take 8" and multiply it by 3.14 you get 25.12". So if you stuck a 8" wheel and turned it one revolution it would travel 25.12" then multiply that by 8000 =200960" a min. divide it by 12 to convert to feet =16746.666666 divided by 5280' =3.171717 multiply by 60 to get from min. to hrs = 190.303mph. Then take a 1:1 of 80mph divide 190.303mph divided by 80mph = 2.378788 for a ratio.
But this is a ratio if you have 8" drivers, if you factor in the height of the track then the height of the lug it can really change. this is a ratio if you only count the driver size. So if you take the 2.378788 gear up then the 2.24 gear down at 8000 rpm and 60/60 gears in a 1:1, then subtract the two and you get = .138788 then multiply it by 80 =11.10 and because its a gear up you add it to 80 to get 91.10mph 57/63 gears 82.42mph 55/65 = 77.08mph
I could be way off on this but its making sense to me.
But this is a ratio if you have 8" drivers, if you factor in the height of the track then the height of the lug it can really change. this is a ratio if you only count the driver size. So if you take the 2.378788 gear up then the 2.24 gear down at 8000 rpm and 60/60 gears in a 1:1, then subtract the two and you get = .138788 then multiply it by 80 =11.10 and because its a gear up you add it to 80 to get 91.10mph 57/63 gears 82.42mph 55/65 = 77.08mph
I could be way off on this but its making sense to me.
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