SX600abuser
Member
Hey, I recently made a small change to my primary clutch which was add the 4.5 gram rivets to the bottom of the weights. This was on Turks recommendations and it greatly improved my overrevving problem. I have been playing with my sled and found that if I pull the trigger from a dead stop I overrev to about 9000 rpm but very quickly pulls down to 8500-8700 rpm, that doesn't concern me, what does concern me is that if I keep on it, around 70mph it starts to overrev to about 9100-9200 RPM. This only lasts until about 80mph or so then it comes back down to around 8500-8700rpm. I am pretty sure it has to do with the secondary. Now my question is, should I mess with it? I don't really like overrevving if I can help it. I have been on different surfaces while riding it to check this, hardpack, fresh powder, lake, everything. This shifting is pretty consistent. Temp was around 15-20*F. Belt was in spec last week, and have no reason to assume it would be out now. I have read all the technical literature on this site and read a bunch of related posts. What do you guys think?

bluemonster1
LIFE MEMBER ONLY ONCE!!!
got my SXR at 4.5 inner and 4.5 outer.But it was a little under reving,so I drilled .5g out of the outer rivets.I am about that 8500ish mark now.Stock springs and red 2ndary.
SX600abuser
Member
bluemonster1 said:got my SXR at 4.5 inner and 4.5 outer.But it was a little under reving,so I drilled .5g out of the outer rivets.I am about that 8500ish mark now.Stock springs and red 2ndary.
Thanks blue. Yeah I have actually read a lot of your posts about your sxr. I have a 99 and I think it is a little hp less than yours stock. I am not 100% sure. I was thinking about adding a little more weight to the tip to see what it does (.8 grams right now), but the way it ran out, made me think secondary is opening just a tad too slow.

bluemonster1
LIFE MEMBER ONLY ONCE!!!
what spring is in the secondary and what is the wrap at...Should be Red spring at 80 stock. Go to 70 is over reving a bit.
SX600abuser
Member
Hey Fellas. Food for thought. I really dived to into playing with the clutches this fall just to see what changed what and I ended on the 8AB weights empty, with stock y/g/y spring primary and red sec. with 80* wrap. also worth mentioning i have a 51/43 helix. I have a under revving issue which makes me still believe the secondary is dropping a little quickly. Pull the trigger and the thing takes off like a rocket sitting right on 8500rpm then after 60-65mph the rpms tapper off badly to around 7800-8000rpm. I am considering purchasing a green spring and setting the wrap to 60* to see what it does. Is it worth my time?
mopar1rules
Active member
i would say you need green spring on that machine w/8ab's. try it at 60deg and see what happens. see if the overshifting problem is cured, w/the stiffer green spring. don't go more than 80 wrap. what brand 51/43 helix you have? might need a shallower finish angle on the helix, or just simply change the primary spring to like a g/g/g or a y/w/y. both have higher end forces, thus wanting to hold the primary from shifting so hard. still my gut feeling is too much finish angle of helix, or that red is just way too soft.
SX600abuser
Member
mopar1rules said:i would say you need green spring on that machine w/8ab's. try it at 60deg and see what happens. see if the overshifting problem is cured, w/the stiffer green spring. don't go more than 80 wrap. what brand 51/43 helix you have? might need a shallower finish angle on the helix, or just simply change the primary spring to like a g/g/g or a y/w/y. both have higher end forces, thus wanting to hold the primary from shifting so hard. still my gut feeling is too much finish angle of helix, or that red is just way too soft.
the helix is a yamaha oem from an rx1. I was thinking the 60* too, to start off with the green spring. I have one and I will probably throw it in tomorrow night or this weekend. If that doesn't solve it I will probably use your suggestion about thowing a more of an end force spring into the primary. Can we get another opinion on the matter to make sure mopar and I are on the right track? Thanks mopar.
primary ywy, sec. raise bottom angle to 45 or 47, wrap spring at 60-70, have you ever tried a straight 47, the only reason you need to use a multi angle helix is if you want a better take off, but unless you are racing, I see no need for a muti. I use both in my race sleds depending on if I radar run or drag race.

bluemonster1
LIFE MEMBER ONLY ONCE!!!
got my 600 running good today..clutching is right on,fixed th track racheting issue and runs good in 2 to 3 feet of snow..keeps the rpm's.Have stock weights with 4.5 in both holes.WOT is 84-8500...only thing I used a single layer head gasket after the rebuild and seems the gaskets are letting coolant thru.Takeing apart tomorrow and putting stock gaskets back on..I am running red spring at 80 wrap with 47 helix(stock).I could try the 51/43 I have,but don't want to touch the primary any more.I wander what the 51/43 will be like...hmmm??