09 M8 clutching help

[iluv2fly]

That was me with the different spring from racinstation. Out of all the setups I would install the 70's with the slp blue/yellow 140/310 if you have a 162. I have since installed the slp pipe on mine and run 70's with a 150/330 spring and get 7850-7900 in a climb, works very well. Mine with the 162 just wont turn the proper rpm in the really deep snow with the 73's and I talked to eric about this today and the powerclaw hooks up much better and loads the engine harder. I went up to 8 mile with my buddy on his 07 M8 and boy what a difference the track makes. His would spin like crazy and trench where my powerclaw would stay on top and just hook up like crazy. Install the 70's and change the primary spring and I would bet it's much better. If you want to try the heavy spring route with the 73's than order a slp 140/340 and that will help hold rpm much better.

 

[dunatyk]

Cleaned clutches changed belt with the one off of my 07 M8. No change really other than the marks i made in my primary with a sharpie showed that it is shifting out a little farther. so my question is doesnt a stiffer primary spring keep it from shifting out farther? Also if i remember my reading from cutlers clutching handbook that you should always adjust your peak rpms with your weights? I have seen it done with a spring before but do not know if this is the correct way. Also are there any shims behind anybody elses secondarys. Mine has none at all. Going to pull the clutch off of my 07 and see if they are present there. One more question does less weight equal less top end pull because there isnt enough weight to overcome the primary spring?

 

[jeffro]

SledJunkys!

After reading this whole thread, it seems like you guys are chasin' your tails a bit. I know clutching can be a real mofo to solve sometimes. Have any of you tried SledJunkys kit? Ron really knows his Cats and Clutching. Coxy- give him a ring and ask him what he recommends.

You've covered the basics- Alignment, offset, CLEAN, well-maintained clutches etc...

OR, you can always purchase a copy of Olav Aaen's "Clutch Tuning Handbook" It is the Bible of clutch set-up. It made my '01 800 RMK the sled to beat with just and SLP single & intake. (Nitrous, Turbos & BIG-bores excluded)

Good Luck!

-Jeff

 

[Coxy]

Thanks Jeffro, i actually used ron's kit on my old M7, and ill give him that, it made the sled a whole different animal. I am just hoping to find a relativly easy/not too pricey solution to this thing. I need to get up and try this 120/340 spring with everything else as it came, just to see if it reacts any better. Engagement is about 300rpm lower, i already know that, so hopefully boxing day will be my chance to test. I really appreciate everyone chiming in in this thread though, theres alot of good idea's, suggestions, and info so far, looks like it'll be one of those threads that can help a brother in need out. The cool part is me and a buddy have identical sleds, down to the boss seat and MBRP cans, other then the fact i out weigh him by i would guess 50 pounds, so it will make for a really good comparison with any changes.

 

[Coxy]

Oh, and Merry Christmas boys!!1

 

[iluv2fly]

Cleaned clutches changed belt with the one off of my 07 M8. No change really other than the marks i made in my primary with a sharpie showed that it is shifting out a little farther. so my question is doesnt a stiffer primary spring keep it from shifting out farther? Also if i remember my reading from cutlers clutching handbook that you should always adjust your peak rpms with your weights? I have seen it done with a spring before but do not know if this is the correct way. Also are there any shims behind anybody elses secondarys. Mine has none at all. Going to pull the clutch off of my 07 and see if they are present there. One more question does less weight equal less top end pull because there isnt enough weight to overcome the primary spring?

Less weight does not mean less topend performance. Less weight will help the engine reach peak rpm and stay there so the engine is making the most power. If your worried about a stiffer spring than try the 70's with the stock spring or cat orange/white. Mine with 70's pulls unreal.

 

[Bounty Hunter]

Rpm,s

Took my new M8 out ,rode8/10000ft. Had 73grms in it, didnot get more than 7500. Put 68wts in it now get7840. I have a D&D shim kit And a shift kit in it. Works very well now.

 

[Bacon]

yesterday rode at 10,000 feet all day with the 70g and could only pull 7650... snow was still at least 3 feet deep but setting up.

Have yet to put on the SLP single, but i am hoping i can stick with the 70s though i feel i might have to drop to the 65-75 adjustable weights...

Phatty, just an FYI, I ran my M8 with slp pipe and slp 71g weights and it was nuts on at 9-10,000 feet.

 

[GlennRMK]

Any updates guys?

I installed the D&D torsional kit and BDX 42/36 progressive helix

Only had a chance to tool around the yard, so I can't comment on RPMs

Trying to get get out this week

 

[Coxy]

I went out boxing day. Found some decent snow, probably about 3' untouched, with granite as a base haha. Sled seemed to turn alot of RPM with that 120/340 spring at 6500 feet. It was hard to say if it was stable or not, as the hill we were playing on was pretty steep, and bad news if you went down too far. As far as i could see the odd time i got a chance to look, it was pulling 77-7800 rpm, some more, some less, with 38-40mph track speed. Like i say, wasnt ideal for testing, as it was fairly bumpy, and sidehill madness. Belt/clutches got hot as hell, but i cant blame them, as my first pull up/through that bench was probably 2 minutes of being taped to the bars. Cords still poping from the belt, and a very slight rubber mark on the primary at mid shift. The sled seemed to work pretty good, but still am not impressed with the M7 track speed. Wondering if i might be wise to split the difference on the finish rate of the primary spring, and cut the weights to get the RPM range right? On the trail the sled feels like an animal, but almost seems to have that feeling that its not shifting/pulling as steady as it should be. Anyone else have any more playing with this thing yet?
Brian

 

[iluv2fly]

Best thing to do is install some 70's with the stock yellow/white or orange/white cat spring and compare clutch heat and track speed to see how they compare.

 

[Bounty Hunter]

clutch set up

I ride 09 M8 at 8/10000 ft. Have a can and D&D shim kit. Had to go to 68wts with to get 7740rpms. Track speed is not good. Going to try stiffer spring The 78wts are to heavy for me. I rode over the weekend sled goes thru power and climbs very good. I need 78/7900rpms to get my max hp. Also I have a D&D shift kit which I believe cuts down 1/2 hundred rpms.

 

[Icedog]

I ground my 73's down to 71.5, running the stock spring, and RKT 38/36 secondary. Seems to work really well in all conditions. I let off in a pull a bunch of times while testing and got back into it to see how the clutches would react. She snapped right back to 7800 and held RPM everytime. Clutches were both still totally clear of any signs of belt slippage at the end of the day as well. With the 73g weights; when I let off in a pull I couldn't regain full RPM. This was an '08 M8 at 6500-8000'; stock pipe/engine; D&D Y-pipe, Firebreather, and can.

 

[Coxy]

Thats next luv2fly, think ill try it another time on a better testing hill, and see what and how it pulls with just the heavy primary spring. Then see if i can score some 70/71's and go with the stock spring. Ahhh the joys

 

[Gvrunyn]

I too ground down my stock 73s to 71g and it helped alot with the upshift. mine has a slp pipe kit on it and i expected it to pull the 73s but it wouldnt. Changed the primary spring to a team green and that also helped but i still can not hold the rpms on the hill or in the deep I would like to try a driven spring with about the same pretension as the stock orange but more shift rate Does anyone know of a spring like this that will fit the 08 M8 . Oh yeah i also put the shift assist in and did not notice any diff. Any input would be great! Great post by the way

 

[CATSLEDMAN1]

M8 clutching

I ride an 07 M8 153.

last year I ran cat 72 gram weights cut from 75's gold cat primary, orange spring secondary / shift assist with 05 spring adjust 42/36 helix and adjuster in about 2 turns stock track. Sled pulls hardest at 7700 with orignial old fat box.

This year.......... powerclaw track, went back to 36 helix, 2 plus turns in on adjuster, dropped about 2-3 mph track speed, picked up about 4mph ground speed maybe more. Any clutching hard and fast numbers comparison between powerclaw and other tracks is likely not too relevant.

I have set up three sleds this fall with 55/65 gearing, sure irons out a lot of inconsistency and way way better at getting back to rpm when in a steep hill.

Will set my own sled up with lower gearing next week depending upon what's shipped and backordered, will be a good comparison on clutch changes.

For guys fighting with M8 RPM fluctuations, using the stock no spring adjust "bald head" helix makes tuning real tough and looks like it leads to some big hits on the wallet with poor results. These cheapo helix's were built so you couldn't fool with them or your sled, but your are? Aluminum scrap!

Also noticed stock to dalton to BDX helix's same numbers don't all respond the same. 2 gram weight difference sled to sled is not unusual and shouldn't be alarming.

And it snowing like heck again.........all good.

 

[Bounty Hunter]

M8 2009 clutch set up

I ride at 9/10500ft 190pounds. I went to 68 wts, D&D tan spring 150/330 and ti runs7800/7900. I also have a D&D shim kit, shift assist. When I used stricty stock set up I only turned 7500prm. Hope that helps. Buy the way most of the 800 sleds around here we found clutch align wrong. HAPPY HOLIDAYS

 

[phatty]

iluv2fly,
so your pulling 70 weights on the SLP single? that is what i want to hear! SLP said to pull 8000-8100 on the pipe, if im ball park 8000rpms at 9500 feet i will be happy!

Im off to new orleans for the weekend wed night, but i think tonight i will put the SLP pipe on and the 130/320 titanium spring with my 70 weights and do a little ride tomorrow morning and see what i can pull.

I have a great situation to compare with. Dan G has an 09 m8 with SLP single and has 73's with the stock springs/helix. So far my stock HCR on 70 g weights has gone neck and neck with his (keep in mind im 60lbs heavier than he is). He only pulls 7400 though.. His sled feels so much stronger through the mid range but not on top end. Im hoping that the drive spring and lighter weights with the SLP pipe will own his sled. Nice that i have a baseline to test against!!!

 

[GlennRMK]

Keep us posted on your results phatty

I am interested to see what the torsional setup does

I also bought a set of 70 gram weights in case the RPM is down, which it seems it might be from riding around the yard. Hard to compare though as the elevation is lower, but the pipe is definitely not as hot.

 

[dunatyk]

Ran mine last Saturday same riding area as the week before. i pulled better Rpms 7500-7600 with the occasional 7700 when climbing. Snow was about the same depth but not quite as heavy. Dealer told me to wait until atleast 150 miles before I strt messing with any weight changes. I think after the 150 miles if I am still not hittting peak RPM i will drop down to 70's and see what she does