M8 Low Altitude Setup - What works?

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WIrider

New member
Ok guys I need some advice on what works on your M8's for low altitude. I picked up a 2009 HCR last spring on way out to TOG (letting the Switchback go)and now need to get it set up for the Keewenaw. Only modification on the sled is a BMP Y-Pipe. I am going to leave balance of engine stock. So I am thinking basically clutching work. What combo's are working for you guys that are still basically stock in power department? Was looking at some of BMP's kits.?

Thanks.
 
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Firecatguy

New member
Bill,
i ran the stock clutch setup untill i got the slp kit now i run there set up!!!I will get you the helix and weights numbers today!!!!!the new setup is smooth!!!with your ypipe you may need to change weights out as it might rev higher........
 
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cuzzinolaf

Well-known member
Firecatguy said:
Bill,
i ran the stock clutch setup untill i got the slp kit now i run there set up!!!I will get you the helix and weights numbers today!!!!!the new setup is smooth!!!with your ypipe you may need to change weights out as it might rev higher........
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I didn't need any change my weights on my 2008 with a Y-pipe. I think all sleds are different because my 2010 runs 8450 RPMs at WOT. I need to get slightly heavier weights. As long as his RPMs are 8200 or below he should be fine.
 
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Firecatguy

New member
8400 WOW!!!!I was told 8200 is loosing power 8100 at max!!!!as far as ypipe yep i had speedwerks ypipe before i did SLP kit but no change in clutch!!!!I did notice that it had build up of wet oil in ypipe so it needed something but not necessarily clutch change...
 
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Skylar

Super Moderator
Staff member
I will check my brothers 08 M8 clutching today. I know he is running the 800 crossfire helix, and I am pretty sure he is running heavier weights. He has an aftermarket y-pipe, and is running a Skinz silencer on it.
 
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cuzzinolaf

Well-known member
Firecatguy said:
8400 WOW!!!!I was told 8200 is loosing power 8100 at max!!!!as far as ypipe yep i had speedwerks ypipe before i did SLP kit but no change in clutch!!!!I did notice that it had build up of wet oil in ypipe so it needed something but not necessarily clutch change...
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Yea, I think it was actually 8450 RPMs on the tach. I know the 2010 800 max RPM raised a little but I'm still way high. Hopefully I got a factory freak and can tame it down with some heavier weights. I still need to change my primary spring so we'll see what happens after my first run.
 
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stealthv

New member
The '07-09s respond to heavier weights in the primary. That generation 800 engine was built for down-low torque, not high rpm screaming like the newer 800 HO. Weight the snot out of it and make 'er grunt for da UP eh.

My '08 has in the primary - Dalton HD/QACA-2W adjustable weights (78.3g @ 1-1.5k' in the UP) and (75.0g @ 6-9k' out West) along with AC gold spring for the primary P/N 0646-376
Stock helix
Stock secondary spring (no shift assist)

The gold spring has nice low just-off-idle engagement making it great for boondocking. Couple that with a gear change (mine's at the more extreme 53/67) for even better UP performance.<!-- / message -->
 
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WIrider

New member
Thanks guys for your input...

Pat, shoot me the numbers when you got'im.

Can't wait to see what the green machine can do in the trees. I just need to stay ahead of baby bro techsledder.
 
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thebreeze

Member
I had good success with a Rk-Tek torsional conversion in the secondary, and 77 gr. weights in the primary, but this is with the SLP pipe setup which likes slightly higher RPM's (8150). I did run for a season with the stock 36 degree helix, and spring, and the proper cat primary weights, and it was a decent setup. The torsional secondary really made a difference in both up-shift and downshift speeds. The secondary does not like to shift out in stock form.
 
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scottd

New member
I've got 42/36 helix, AC 77g weights, shift assist, SLP pipe, 55/65 gears and mine pulls really nice. Could use a tad more RPM I think but happy enough this year it isn't getting touched (other than fixing the mangled up plastic from last season which needs to still get done one of these weekends when I am in the Yoop before the snow falls).
 
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likinit2

New member
I used 77g weights and left the helix alone. It seemed to work just fine and pull hard in the powder. Could use the other helix on the hard packed trails but it really wasn't at home on the trails anyway.
 
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ezra

Well-known member
I have been using the Dalton adjustable weights going on 4 yrs and really like them verry quick to change weight or move weight from toe to heal and if you add a pipe or a head what ever you don't need to buy more weights just change the weight of the ones you have.
 
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WIrider

New member
ezra said:
I have been using the Dalton adjustable weights going on 4 yrs and really like them verry quick to change weight or move weight from toe to heal and if you add a pipe or a head what ever you don't need to buy more weights just change the weight of the ones you have.
Click to expand...

Thanks Ezra. Where did you pick these weights up? Did you stick with the stock helix?
 
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mfire8

New member
Not sure if's it's only high elevation but i heard that the adjustable weren't as good as the stock weights not worth the money? Anyone heard this? I think i read it on SW.
 
favoritos

favoritos

Well-known member
How about just picking up a secondary off a Crossfire and changing the weights based upon where you are riding? It would be a quick change scenario.
 
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thebreeze

Member
Adjustable weights can be very sensitive to weight placement (heel vs. toe) and as you add and remove weight, the center of gravity changes. This does affect shift performance. You can buy 3 sets of cat weights to 1 set of adjustable. I ran adjustable weights for 3 seasons. I have since switched back the cat light tip weights. The benefits were immediately noticeable. I am not saying they never work, but the stock weights are much more consistent. Also, you can change out weights in about 15 minutes, and when you loose a primary roller(s), you are only tearing up a $60 set of weights, vs $150-$200.

My RPM's would constantly hunt back and forth with adjustable weights. Cat light tip's would hold RPM's in a climb all day.

The set screw style adjustable weights only allow for appx. 9 grams of adjustment, which is typically not enough when traveling to 10000 ft. from the mid-west, so you end up buying two sets anyways.
 
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