YZ444F kit?
- Thread starter mxmatt426
- Start date
It's the best bang for the buck you can get on the YZF. Here's some dyno runs from SFO's YZF444 :http://www.four-stroke.com/Dyno_runs/SFO_index.htm
Tony Williams
LIFETIME SPONSOR
- Mar 23, 2000
- 592
- 0
What's the costs involved?
Does it matter if its a 400 vice 426?
Durability compared to the 450?
Does it matter if its a 400 vice 426?
Durability compared to the 450?
It seems like on those dyno charts, the MTBE is practically doing nothing. I thought that it would provide more significant gains than that.
The reason I ask is that recently I experimented with the VP Ultimate 2 (Which I assume's main oxy. adding ingredient is MTBE) and couldn't tell any real gains racing at the sand dunes.
I ran back to back with VP C12 and Ult. 2 and the C12 might of been faster. I raised 1 main jet size with the ultimate 2.
Is there something else I need to do to take advantage of this fuel? Or was I just expecting too much out of the $9 a gallon fuel? All that I really got out of it was a lighter wallet, and a really strong smelling bike.
You can't hide the fact that you're running something different with that fuel.
The reason I ask is that recently I experimented with the VP Ultimate 2 (Which I assume's main oxy. adding ingredient is MTBE) and couldn't tell any real gains racing at the sand dunes.
I ran back to back with VP C12 and Ult. 2 and the C12 might of been faster. I raised 1 main jet size with the ultimate 2.
Is there something else I need to do to take advantage of this fuel? Or was I just expecting too much out of the $9 a gallon fuel? All that I really got out of it was a lighter wallet, and a really strong smelling bike.
You can't hide the fact that you're running something different with that fuel.
Last edited:
SFO
LIFETIME SPONSOR
- Feb 16, 2001
- 2,001
- 1
My dyno tuner guru speculated that all the 02 did was mask rich jetting.
There was a lengthy thread at one time covering said issue.
The high compression piston is fine with pump.
I ran pemex in mine with no detonation.
We ran nutec on the racebike all last year and the jetting was unchanged for every location.
It is nice to have one less thing to do before a national...
The 400 actually has a closer gearset the the 426 and might be considered more desireable if you factor out needing to upgrade the rod to 426 specs to use the 97mm piston due to the wrist pin size variation.
There was a lengthy thread at one time covering said issue.
The high compression piston is fine with pump.
I ran pemex in mine with no detonation.
We ran nutec on the racebike all last year and the jetting was unchanged for every location.
It is nice to have one less thing to do before a national...
The 400 actually has a closer gearset the the 426 and might be considered more desireable if you factor out needing to upgrade the rod to 426 specs to use the 97mm piston due to the wrist pin size variation.
