8-10,000 clutching

[AdrenalineAddict]

Track,
It's normal for a little guy to require lighter weights than a big guy, less load, less resistance, more upshift. Over the years I've seen a 100-200 RPM difference between a 200 pounder and a 160 pound rider.

 

[phatty]

if you are over 200lbs i would run the 10-58s at 9-12k feet.
lighter weight guys can get away with 10-60s at that elevation.

i run the 58's my self with stock springs (i weigh in at 200lb) tacks out at 8200 all day long. ride 8-11,000 feet here in utah.

buddy weighs 140 soaking wet, runs the 60s and tacks out at 8250 all day long. same elevation.

 

[goforbroke]

Interesting? One built on a Monday and the other on a Friday?

Same rider weight, gearing, ethanol plug setting, track length, and cylinder compression?

didn't check compression, but yes on the rest. I even tried 10-60's in mine and lost rpm and performance, not worried as they perform the same with the right wieght in. Maybe my spider is a bit heavier?

 

[Old Scud-doo]

I would buy an allen wrench and regular wrench to fit your weights. Sorry, but 400 rpm in loss can result in as much as 4 to 6 mph loss in track speed. That's huge when trying to get out of some place ugly...or into some place ugly. Super easy to do.

 

[Snowbird11]

I would buy an allen wrench and regular wrench to fit your weights.

if you're running factory hardware, that'll be an 1/8" allen wrench and a 3/8" midget wrench.

 

[03 980g2]

I ran the 10-60s on mine at Tog last year with stock springs and ran about 8100.I brought the black purple with but was too lazy to put it in.

 

[rotax]

I was running stock primary spring, 10-62, Black/Purple, 3 delrins at 6500-9500 ft.
I weigh ~175# geared and ready to ride.
If you're any heavier and want to stick to stock weights/springs, I'd prob go 10-60 for ~7-10k.

My only regret is I didn't go to MDS weights sooner.
They pull harder, back shift better, noticeably better belt 'clamp', and best of all are ADJUSTABLE.
Sounds like a pitch, yeah... but so far a solid upgrade, that is highly adaptable for later [HP] mods.

 

[benschroeder222]

what is everyone running in their pro in Cooke? i'm about 165 lbs all geared up. its an '11 163"

 

[clamlake600]

I use the black/purple or whatever the stiffer spring is in my 2ndary, and prefer it.
But, I use it every ride @ 7-10k.

In your case, I wouldn't bother.

With the 13's added drivetrain efficiency it'll probably matter less.

i have a 2013 prormk800 and will be in jackson, wy and bridgerforest area next week. i believe its roughly 7-10k? i just installed black/purple in secondary also. may i ask what weights you are running. i weight 160 (if that matters) i have 10-62,60,58 at my disposal... thank you!