Settings:

*New needle at fourth notch down.
*New main jet is 140
*Mixture screw is 3.5 turns out.

*Old needle was 4th notch down.
*Old main jet was 140
*Old mixture screw setting was 1.5 turns out, if even that much.

The main difference I think is the new needle. As for spending 50 bucks on it, yes it may be a bit much (I actually spent 100 because I have two Hawkeye's and I did it to both of them) but when you spend $4,500 each, and $9,000 total for two quads a measily 100 bucks for this performance increase is WELL worth it. Trust me!

@Mongrol - I live in Oregon. Winter temps are 25-40, Summer temps are 55-95. My elevation is 50 feet. However, I go riding a lot in the mountains which puts me at about 3000 feet. For this change in elevation I use a TPI valve =) (which I just purchased)

=)

 

Thanks for this info. It amazes me the difference performance levels we get from the Hawkeyes. Mine is totally stock and performs great. Base operating altitude is 1960 ft. and the bike pulls and performs great up to 6,000 ft. Then the sputtering starts but will go ok to about 6,700 ft.

Beats me what the difference is. Even with the tracks making it work hard, it will still go to 6,000 but at a walking speed.

Let us know what the tpi valve does for you. I disagree with how it does what they claim, but more air usually helps.

Good luck.

 

WHATS A TPI VALVE?

 

I thinks it like a trap door for the airbox lid that lets you open and close it as little or as much as you wish.

 

Its like sheepdog says. Its a partial cure for a machine that has not been correctly set up by the factory or dealer such as not installing updates.

 

Factory calls for a 147.5 main jet to 6000 ft. The 140 would appear to be very lean. You're at sea level and I can't imagine needing it much leaner. Fac. specs for 6000 - 12000 ft is for a 142.5. If Dynojet uses the same numbering system for the jets, That may be critically lean. The idle mixture at the old setting makes me curious. The change in that area might account for some of the off idle performance increase.

Keep a close eye on the spark plug for signs of a lean mixture because an engine produces max power at the critical point of going from ok to lean and also that is close to melt down (depending how you're riding).

Be really cautious till you see what is happening.

Good luck