I just bought a 06 M7 153 completely stock with 1100 miles on it. Im at approx 2100 ft running a 44/40 helix, stock springs and 73g weight. Cant seem to pull full rpm. Can manage to squeeze 71-7200 rpm in deep snow, on hard packed I can get 7800. What can I do to smarten this thing up. Will a straight 36 helix do it? or combination of helix and springs? I also put a MBRP can on it and it developed a nasty bog at around 6000 rpm. I have heard that some of these 700s dont like MBRP, what other kind should I look at so I dont have to have a briefcase under the hood?
2006 M7 clutching
- Thread starter Mukker
- Start date
raise your r's
Try to take a little weight off your arms, try 1 gram first , more towards the tip , shoot for around 7800-7900 on a hard pull or over spin just little..8000 at the start. make sure your belt is in good shape-- bad belts will drop some r 's ( may want to try a new belt first) I ran a 06 M- 7 with bikeman pipe, reeds, mrbp can and open the box up alittle ( 72 grams / 44-40 helix. with rk-tech shift kit--worth the money too ) before going to a rk-tech big bore----well worth the money-- one strong 800 with a power claw track -- I ride from 3000-7500 ft -worked good except up towards the high end (7500 ft)!!! 7's like to spin freely so the sooner you get the r's up the better you will like it ---one of the best sleds out there
Try to take a little weight off your arms, try 1 gram first , more towards the tip , shoot for around 7800-7900 on a hard pull or over spin just little..8000 at the start. make sure your belt is in good shape-- bad belts will drop some r 's ( may want to try a new belt first) I ran a 06 M- 7 with bikeman pipe, reeds, mrbp can and open the box up alittle ( 72 grams / 44-40 helix. with rk-tech shift kit--worth the money too ) before going to a rk-tech big bore----well worth the money-- one strong 800 with a power claw track -- I ride from 3000-7500 ft -worked good except up towards the high end (7500 ft)!!! 7's like to spin freely so the sooner you get the r's up the better you will like it ---one of the best sleds out there
I have 06 m7 with super-Q can,Bdx intake,Stock spring in primary,Orange with shift asist in secondary,67 gram weights,36 helix,no preload on secondary spring.I pull 8040 rpm at 7500 elev. If i were you i would keep the 44/40 put 70 grams in primary and orange with shift asist and no preload in the secondary. Also throw a new belt on. I have no bog and it rips good. Hold rpms good.
I'm gonna disagree with both previous posters, my experience shows me less weight in an M7 kills track speed. With stock primary spring you should pull 75g. cat weights at that alt. With the stock white secondary spring, you will have no backshift if it has no extra preload (the reason you only pull 7100 in deep snow). The large white plastic donut inside the helix with 6 holes in it that the spring rides on...it should be at least 1/2" from the outer face of the aluminum cover, and with that helix, 3/4" is not too much. You will need a special wrench to adjust it.
For more fun, go with a straight 36 or 38 helix and cat orange spring with shift assist in the secondary...if you can't pull 75g. weights with either of these setups, start looking for why you are down on power.
For more fun, go with a straight 36 or 38 helix and cat orange spring with shift assist in the secondary...if you can't pull 75g. weights with either of these setups, start looking for why you are down on power.
If I were you, I would get your hands on a cat orange spring and shift assist, leave everything else alone at first, try that and see what your r's do. If you need more or less, make a primary spring or weight change to get spot on. I would keep the 44/40 at that elevation, going to a straight 36 will kill the bottom end. I'm running a 40/36 at 5000-8000... so a 44-40 down low should work great.
I'm guessing that white spring backed the adjuster out to the cap and that's why your not backshifting and pulling rpms when under load. Get the orange and shift assist, and leave the adjuster out, well worth the money.
I'm guessing that white spring backed the adjuster out to the cap and that's why your not backshifting and pulling rpms when under load. Get the orange and shift assist, and leave the adjuster out, well worth the money.
Will the 36 helix get me more power out of the hole? I like power in the bottom and mid range. If I only get 65-70 mph out of it Im ok with that. I want this thing to hold the skis off the ground!!! It has a ultimax belt on it, does that make a big difference?
Raise the R's
There alot of advice out there, when you change apart, only make one change at a time. try to increase your pressure on your driven, new belt, new springs, shift kits, add or take off weight. You can try any of them. What work for some else may not work you. As your ridding style may not be same. If you got a good Cat mech near ---go talk to him-- But you need to raise your R ' s --- 36 helix is used at a higher elve. normally so it lets the motor spin up quicker because of less hp. would not pull as hard as a 44/40 down lower. Cat push that helix for 6000-9000 ft on their high alt. kits. get the R' s where you want them the work on the shift pattern. as for the plastic spacer in driven, that why I went to RK tech kit could not keep it from backing off. Plus pickup good back shift and a lot of more spring choices. Hpoe this help!!
There alot of advice out there, when you change apart, only make one change at a time. try to increase your pressure on your driven, new belt, new springs, shift kits, add or take off weight. You can try any of them. What work for some else may not work you. As your ridding style may not be same. If you got a good Cat mech near ---go talk to him-- But you need to raise your R ' s --- 36 helix is used at a higher elve. normally so it lets the motor spin up quicker because of less hp. would not pull as hard as a 44/40 down lower. Cat push that helix for 6000-9000 ft on their high alt. kits. get the R' s where you want them the work on the shift pattern. as for the plastic spacer in driven, that why I went to RK tech kit could not keep it from backing off. Plus pickup good back shift and a lot of more spring choices. Hpoe this help!!
I think something else is wrong. With 73's you should be hitting better R's than that even with a stock setup. Check your valves, make sure they are not stuck and are working properly. They open @6700 rpm, check it on a stand.
And put your stock can back on and see if your problems go away.
And put your stock can back on and see if your problems go away.
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Yes the ulitmax belt makes a difference. That is a softer belt and will grip the clutches much better. You will have to drop 4-5 grams in weight just going to that belt vs the stock cat belt.
The problem is with your wieghts. Don't mess with your secondary until you have that fixed first. If you mostly trail ride, the stiff orange spring in the secondary will be ok, but will kill track speed in DEEP powder.
The problem is with your wieghts. Don't mess with your secondary until you have that fixed first. If you mostly trail ride, the stiff orange spring in the secondary will be ok, but will kill track speed in DEEP powder.
