raising engagement RPM

roudyroy1

roudyroy1

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ontario GTA
2001 sxr is clutched accordingly; stock weights, 4.5 in the tip and 3.6 in the heal, 51/43 dalton helix @ 60 degrees. stock springs all around. 21/39 gearing, peak rpm is 8350-8400ish

looking to raise my engagement RPM from stock 3500 to 4300 area. how do i go about doing this without throwing off my clutching? engagement shimes? im looking to have the sled launch a bit harder off the line.
 
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If your going to cut your own, cut one at 1/8, one at 1/16 and one at 3/32. Or something close to that. Then you can mix and match.
I think you'll need more than the 1/8" slice to get to the target RPMs.
 

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You can increase the primary spring preload and try to keep the rest the same. I believe you want your shift rpm to be 8400-8500RPM. For example:

Your spring is a y-gr-y preload of 40, spring rate of 2.5 total force of 123.
w-w-w spring, preload of 45. spring rate of 2.25, total force of 119. (decrease shift rpm)
y-w-y spring, preload of 45, spring rate of 2.5, total force of 128. (increase shift rpm)

Increase your preload should bring it up near 3800-3900RPM if I remember.

You will need a long cap spring, for your reference:
http://totallyamaha.com/snowmobiles/aaTECH/drivespecs/primary_springs.htm
 
how many rpm would, lets say the w-w-w spring bring down my shift rpm? i have heard alot of guys shift rpm should be around 8250-8300, always thought i was over revving. maybe not.
 
Hard to say but maybe 100RPM, to counter act that you would drop some weight from the tip of the weight. or Vise versa if you went y-w-y increase tip weight. Another option if you go with w-w-w is increase the tension in the secondary 10 degree's. That will increase the shift RPM, kind of a last resort if you don't want to play with the weights and it's easy enough to do.
 
ill give the Y-W-Y spring a try and report back once the snow fly's. looking to come out of the hole a bit harder as a 600 twin was getting me off the line. just seemed like it was taking long for me to spool up and get on the power (as i have no power valves). it was a poor traction day and the 600 did have a extra .5 in lug over mine.
 
What kind of track are you running and how is your suspension set up? Sounds like your not getting a whole lot of transfer. What kind of 600 twin are you running against. They can be equal power to the 700 redhead and a little lighter.
 
1 inch hacksaw (getting to the end of its life) , no studs. rebuild rear skid as to BETHEVIPER's write up. limiter straps are longer than stock settings, adjustable transfer rods @ 50/50 gap FRA set in the middle, slight preload on the center shock. sled is setup with stock weights, 3.6g tip and 4.5g heal. stock springs with 51/43 dalton helix in the rear wrapped @60 degrees, 21/39 gearing, reed spacers and drilled can. was running against an 03 600 rev and a 13 renegade 600 e-tec. can pull them on top, just get beat out of the hole bad.
 
Sounds like you got your suspension set up perfect for regular trail riding and playing around. Do the ski's come off the ground at all?
 
if i hook up well they will unload alot, maybe slightly come off the ground. it rides really nice on the trail and doesn't push much when getting on the gas out of a corner
 
roudyroy1 said:
if i hook up well they will unload alot, maybe slightly come off the ground. it rides really nice on the trail and doesn't push much when getting on the gas out of a corner
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you should be able to get those ski's off the ground no problem even if you don't hook up well. adjust your transfer rods for some more transfer and report back. sounds like your just not getting enough transfer. it's easy enough to do and if you don't like how it reacts you can always go back.
 
pete_man26 said:
you should be able to get those ski's off the ground no problem even if you don't hook up well. adjust your transfer rods for some more transfer and report back. sounds like your just not getting enough transfer. it's easy enough to do and if you don't like how it reacts you can always go back.
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ill try a higher pre-load spring as i want higher engagement and wouldnt mind a quicker back shift. ill back the transfer rods off some too.
 
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