MCX 180 clutching help.

[snowspud117]

Im blowing to many belts.
I have MCX setup in the sled now. engages ok, top end ok, but to much belt heat. i think its slipping in the secondary.

any set ups that are working would be much appreciated.

 

[Thistledoo]

18 or 19/40 gearing

What helix?

 

[summitboy]

You need to give the following:

Primary-
Spring
Weights and rivets
Rollers

Secondary-
Spring (include hole numbers)
Helix

Gearing

Also has the offset been checked ? What year of Nytro ? Any vents or stock venting ? Altitude you ride at ?

Then we can dial in the setup.

 

[SNAFU]

I messed around with my set-up a bit last year trying different secondary springs and shock-wave helix. What seemed to work best for me is:

Primary:
8BU weights loaded
14.5mm rollers
BWB spring

Secondary:
Stock 39 deg helix - wound to 70 deg
White Yamaha spring

19/40 gearing

 

[RMG]

I have the same problem with blowing belts. Running MCXs recommended setup (whatever that is). It appears that my belts are coming apart due to heat. MCX recomended 90 on my secondary and I have backed that off to 70 which cut my belt usage way down. I was previously blowing a belt about every other ride. I would still like to buy less of them though.

 

[summitboy]

U guys need to get more specific on the clutch setup. Hard to help with guesses. If your running the stock secondary spring it most likely is too soft. Most turbo setups run a Cat green or a EPI purple wound to 10ish degrees. Most turbo secondary clutches ive seen run a 47-51 helix. My experience with the 180 kits is limited but the above secondary helix and spring have been used on 230-300hp machines. The 8BU weights with the heaviest rivets may be a tad to heavy imo for 180Hp. If it was mine i would start with the following:


Primary:
8BU weights (lightly loaded LOL)
14.5mm rollers
BWB or BPB (softer engagement) spring

Secondary:
47 deg helix - wound to 10 deg
Cat green
20/40 gearing for lightweight rider with a 162
19/40 gearing for heavy rider with 162
18/40 gearing for heavy rider with 174

Its what i would try. You see MCX and guys running more wind because the stock spring is kinda light i believe. The stock spring is made for a 100hp sled at altitude. Winding it an extra 20% will do nothing for the secondary with an extra 80HP. Opinions ?

 

[SNAFU]

Sorry, I miss typed. No such thing as a BYB spring. I meant BWB and changed it in my post above.

I tried the Cat green spring wound to 10 and my shock wave set between 43 and 45 deg. Even with the much higher spring pre-tension of the cat spring, the secondary seemed to shift out too soon and the sled wouldn't seem to run above 8200 rpm on climbs. It may have been the shock wave, I do not recommend these by the way, but I changed out to a 39 deg helix and white secondary spring and I was running about 8600 -8700 rpm with better backshifts.

162" CE track by the way.

 

[summitboy]

It may have been the 8BU loaded that wouldn't let your sled rev. Were you using the heavy 4.5 gram rivets ? I used to run those in a 260 Apex. They were a little light. Prob perfect for a 240-250 sled.

Your right the old shockwaves were junk. I think the newer style is better but i don't use it anymore. Its on a spare secondary in my trailer used for a rescue if need be.

I was told to try a 47 helix after running a 51. It worked very well imo. His sleds all run the 47.