yz125mm700
New member
i just had a quick question for you guys. i have a 2000 mm700 with some basic mods, headgasket mod, boost bottle, dyno port can, reed spacers, and i put a 144 on it. my problem (i think its a problem) is when we go out to west yellowstone and i am climbing or boondocking all the track speed i can get out of it is around 30-40mph! when im on the trail it works fine other than it over revs to about 9000. is this normal?
yz125mm700
New member
oh yeah im going to clean the clutchs to becuse i havent done that in a few years. all i did last year was spray them off with compressed air and then wipe them clean. i havent dissasembled them to clean them.
Based on your mods I don't think those speeds are out of the ordinary for climbing in pow on a steep hill. At 9000 you're over your peak power by 500 or so rpms (does it pull that rpm on the hill as well or just on the packed trail). A little more tip weight will pull the motor back down and may help increase your track speeds.
mod-it
Member
I would agree that those track speeds aren't completely unreasonable, but they could be better if your over turning your r's and haven't taken the clutches apart to clean for a few years. Both of these things are huge in keeping up performance.
rpm's: Like Ryan said, add some weight to the primary and try to get them closer to your peak rpm. I don't know what peak is on a MM, but from what Ryan said I would assume about 8500. I have my sled set up to over turn the r's about 200 rpm on the trail, when I head up a hill in powder the load pulls them right into the sweet spot.
Clutches: Take those suckers off and clean them more, you'll be amazed what a difference it makes. I only take the primary off and clean at the start of the season, but I blow it out and use a green scotch brite pad on the belt surface several times a season. The secondary I always take apart and clean, once at the start and then about every fifth ride. Clean, smooth clutches = less resistance. I also clean the belt and rough up the side of it a little bit. Use warm, soapy water on the clutches, don't want any residue left on them from any type of cleaner/solvent.
You put on a 144, what track did it have before? You may be able to get a really nice increase in track speed if you didn't change your gearing. Do a search on this site and see what others with MM & 144 are running.
rpm's: Like Ryan said, add some weight to the primary and try to get them closer to your peak rpm. I don't know what peak is on a MM, but from what Ryan said I would assume about 8500. I have my sled set up to over turn the r's about 200 rpm on the trail, when I head up a hill in powder the load pulls them right into the sweet spot.
Clutches: Take those suckers off and clean them more, you'll be amazed what a difference it makes. I only take the primary off and clean at the start of the season, but I blow it out and use a green scotch brite pad on the belt surface several times a season. The secondary I always take apart and clean, once at the start and then about every fifth ride. Clean, smooth clutches = less resistance. I also clean the belt and rough up the side of it a little bit. Use warm, soapy water on the clutches, don't want any residue left on them from any type of cleaner/solvent.
You put on a 144, what track did it have before? You may be able to get a really nice increase in track speed if you didn't change your gearing. Do a search on this site and see what others with MM & 144 are running.
yz125mm700
New member
ok thanks guys, i also have a different set of weights with a different profile on them. i was reading Mrvipers article, mabye if i get the numbers on them someone could tell me how this would change things. MM's start life as a 141, so i didnt change it much. i did'nt think thats enough of a change to require changing gears.
A K MtnViper
New member
Try changing the twist on your Secondary clutch to some where between 90 to 110, I bet your at about 70.
This should get your back shift to happen sooner and help you hold better track speed when climbing Imo.
This should get your back shift to happen sooner and help you hold better track speed when climbing Imo.
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yz125mm700
New member
yeah i am set at 70. my whole set up is this...8cr weights (AL .8 gram tip, steel 13.9 gram on the inside) yellow/white/yellow spring. secondary has a green spring set at 70% and a 38bv helix. so how much weight should i add to the tip? the next rivit up is 2.4 grams. would that be to much? i also have a set of 8df weights, silver primary and a green/white/green secondary. all of that came with the sled when i bought.