I live in Co and always ride from 8 to 13,000 ft.
My 08 450 does a pretty good job if I don't come to a complete stop. The problem seems to be the clutches engage at too low of an RPM, just barely above idle. The engine does'nt have the power or torque at that RPM.
I looked at the Yamaha site and it seems they only offer 1 part # for the weights and springs.
The dealer I bought it from said they change the weights/ springs , for altitude on my wifes' Polaris 400 and even tho it has no low range, it does'nt need it. They only rejet the Yamaha.
The Yamaha definitly needs low range, and there's no low range for reverse.
Has any body else noticed this and if so, have you found a way to improve it?
Any after market companies make the weight/ springs, etc?
Any info will be appreciated

 

You should consider an EPI clutch kit or FPS clutch kit. They come with harder srings that gives you transmision engagement a few RPM's higher, just what you need.

 

Does'nt anyone sell just heavier springs or lighter weights?
I checked that EPI and they sell a clutch kit for the 450 for 3 to 6000' elevation for $189. 7000' is about the lowest elevation I ride except when I go to Moab.
I thought I could just buy weights and springs for 20 or $30.
I'm surprised more people have'nt noticed this bog , on a hill from a stand still.

 

The Fix Powersports (FPS) kit comes only with the inner clutch springs, but it cost me about US$100

 

Any one have a link for the FPS clutch. I can't find any where to buy one. I googled the EPI kit but googling FPS just brings up forum comments

 

Fix web site:

http://www.fixpowersports.com/


or the 450s clutch kit directly:

http://www.fixpowersports.com/...0-400-performance.aspx