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Kk gearing for more track speed?

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mattwiles

New member
Feb 24, 2009
20
0
1
44
columbia falls montana
I have a carb, kk with all the slp goodies including clutching plus a challenger ex track, anti ratchet/stab. The sled never bogs on power even in heavy snow, Seems as though it could pull more and I love lots of track speed. Would going one tooth larger upper gear be a bad idea?
 

KMMAC

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Feb 7, 2008
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Mount Vernon, WA
What is your rpm at wot? If it is revving more than 8000 or so then you might get away with it. I thought I read some where here that this engine lives well at 7800 or so.. Changing the top gear one tooth is like adding or subtracting 3 to the bottom..
 

KMMAC

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Make sure your clutches are shifting out. get the back of the sled off the ground and warm the engine and just start adding throttle.. Make sure the track clears the ground well because it will tend to droop in the middle of the skid . Also watch the clutches to see how evenly they work together.
I like the primary clutch to shift slightly faster than the secondary. If the rear spring is too stiff it will bind So this is where color and which hole the spring end is in on the cover come into play Some one chime in here and help with spring colors. Hope this helps some... 7900 is in the ball park so find out what secondary spring is in it if someone else did the work get the info on whose spring was used they very from one dealer to the next.. ONLY change one thing at a time it can get confusing, I like to start with gearing first using the cat recommended high altitude springs.. Just spit balling but they could be yellow green and yellow white if you have the air box they should be on it.. Trust me there are people who think they have it figured out but rule of thumb is start with what is recommended especially if the gear ratio was changed.. Go back to stock mountain springs and try that I may have said that already..
 
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diggerdown

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Apr 25, 2004
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Deer Park Wi.
The best way to check for proper clutcing is on the hill, not a track stand. Draw a couple lines on you clutch sheaves from the center to the outer edge, take a run or two up the hill and take a look at the wear marks on the sheaves. Primary should be within a 1/4" of the outside and secondary should be about the same off center. The secondary reacts to track load and running it on a stand does not give you a true picture. Once you see where you are topping off at, you should call slp and tell them what it is doing and ask them for their recommendation. It is their clutch kit so they would be the most logical choice to ask about changes. What kind of track speed are you thinking you should get? If it never ever bogs dow, it is not being loaded enough. They should backshift but that engine is made to be loaded and not just spinnig free.
 

Meatman

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Nov 26, 2007
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^^^^ what he said

trackstand tuning is great, on a trackstand....but there are a lot of other factors that come into play on the hill.....when you say slp "goodies" what are you all referring to? what are you running for a clutch set up?

before I went with the 975 I was getting 45-55mph trackspeed up the hill, 19/43 gearing, snopro spring in primary running a straight 53* helix, also running a button cover because the rollers tend to crack (unless you get the BDX hard rollers) and my sled seemed to backshift pretty hard. the button cover helped a lot with that.
 

KMMAC

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What I said about clutching on a stand has to do with how well the clutches are working together...
I don't care how good of a rider you are you can not watch the clutches work and using ink only works when you know that the run you make is absolutely smooth. what my point is get the clutches rolling and be able to stand and watch them work through their respective shift range to see if there is any coil bind.. A sled going up a hill that may or may not be smooth will tell you nothing more than the belt,, at some point rubbed the ink off of the sheaves.. Besides I absolutely hate wasting time on the hill tuning.. I've used this method for years if you want to load the engine
and clutches use the brake. Unless the setup I changed was real bad I would ride the day and make changes in the shop..
 
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mattwiles

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Feb 24, 2009
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columbia falls montana
Clutches function perfect, sled has over 170 hp and will currently out climb a Polaris pro. It just seemed like I could spin the track faster and still have plenty of Torque. However the mech at the ac dealer told me I would start blowing belts and my track was only rated for 80 mph, but I think I'll try it anyway thanks for the input.
 
R
Nov 21, 2009
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West Fargo, ND
I started to blow belts when trial rode at high speeds with my 1m, the AC mech is right. If you still want more top end you will need to weaken your secondary spring, but you will start walking your belt up out of your primary.
 

backcountryislife

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Clutches function perfect, sled has over 170 hp and will currently out climb a Polaris pro. It just seemed like I could spin the track faster and still have plenty of Torque. However the mech at the ac dealer told me I would start blowing belts and my track was only rated for 80 mph, but I think I'll try it anyway thanks for the input.

Are you looking for more track speed, or more top end speed? Two different things.
 

KMMAC

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Track

Clutches function perfect, sled has over 170 hp and will currently out climb a Polaris pro. It just seemed like I could spin the track faster and still have plenty of Torque. However the mech at the ac dealer told me I would start blowing belts and my track was only rated for 80 mph, but I think I'll try it anyway thanks for the input.

If you are running the challenger track you will get a lot of track spin it works better in powder but some say the camo extreme works well also I think more so because of how tall the lugs are.. I still suspect your secondary is not shifting right...
 

Rixster

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Oct 20, 2005
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My 900s really liked 20/46 gearing. Yeah it is gearing down just a bit but that allows the clutches to shift out further and actually gave me more track speed.
 
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