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m7 only hitting 72-7500 rpm ???

Vern

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Jun 14, 2004
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hyrum utah
m7 only hitting 72-7500 rpm ??? any suggestions

heres the dealio, ive been playin with clutching a bit lately and heres what i have currently cat gold pri. spring, stock 67 gr. weights(carb model), 42/36 progressive helix with orange m8 spring and shift assist. i ride between 6-9000 ft, and sled is currently all stock with a SLP can. i love the low engagement of gold spring and the pull it has off the line with the 42/36 helix but im topping out at around 7500 rpms and have seen it run as low as 7200 on some climbs. however even though it is only turning those low rpms it is still pulling between 35-40 mph track speed when climbing and still hits over 75 mph on the trail and the clutches are fairly cool. i guess my question is what would be the easiest way to get the extra rpms without effecting my setup in a bad way. lighter weights? how much lighter would i need to go? maybe a spring with a stiffer finishing rate? i ran it with the stock yel/whi spring and it pulled 75-7600 rpms pretty consistantly, just no sweet sweet low engagement which if need be i can do without. im pretty sure its the steeper helix thats loosing the rpms but i like the way it feels. oh well, thanks for any suggestions.

brandon
 
Last edited:
B
Nov 26, 2007
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wow. umm i have a 06 m7 162 with a slp can and i was hitting 8500 rpms today. Sounded like it was hitting off the rev limiter. I had this sled since it was brand new. no clutch work or nething. and i looked at another m7 the track engagement was at 4300 rpms. mine shifts in at 3900.... can anyone explain why my sled is acting so different. the plugs are fine. the belt is correct.. any input cat ppl?
 
S

Ski-Laxn

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Nov 26, 2007
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your setup is good just take some weight off. I went with cutler weights and they are much better then stock. mine are loaded from the heel side. There is a set in swap meet for sale.
 
F
Dec 5, 2001
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back country
It might be that progressive helix...more and more I think I wanna be at 38 deg. in the meat of the boondocking/climbing shift ratio, 35-45 MPH...that progressive, at that low ratio, is probably closer to 40/39 deg?

I've noticed what you have, though, with the M7...better to have "too much" weight than not enough...cause even under-reving, it will pull good track speed, with the weight in there.

John
 

iluv2fly

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Dec 3, 2007
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I noticed just the opposite with my weights. When my M7 was only hitting 7500rpm with 68 gram weights it was lacking bigtime and this last time out with my 64's was the best it has run all year. I was pulling 8000-8100 in a climb and what a difference it makes to stay in the powerband. Now I know mine was a little high but it is also trail ported by slp. Try the 65's and get to 7800-7900 and you will notice a big difference. These sleds are not like the M8's, they love to rev higher and make best power at 78-7900.
 
T
Nov 27, 2007
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more rs

More Rpm = Less Weights

Engagement = Spring

I Run 38 Helix Redwhi Sring Thou I Am Bout 155 Pounds Wet

66 Gram Weights And Stock Ti Spring - I Get 7900 Full Pull

At 10,000 - Am Happy Amd Engages Smooth
 

Vern

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Jun 14, 2004
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thanks for the suggestions, i think i might try lightening up on the weights a bit. maybe i'll give the cutlars a try due to there ease of adjustability, plus i have a set of pipes i might throw on so if i do i wont have to buy anymore weights. thanks again.
 
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