so im a jetting newb - little rant

6 replies to this topic
  • RoughR1der

Posted May 12, 2006 - 01:32 PM


Rode the beast today in the desert. 78 degrees. maybe 4k' alt. 168/48 JDjetting blue needle 3rd clip position.

The old boy was running kinda sh1tty, so I guess i gotta break open that carb again :banana:

as some of you have mentioned with the heat, the 170/48 seems to be too rich now. I'm guessing with my settings I'm also rich with this new heat.

I know it's easy to change, but damnit man I'm LAZY!!!! :busted:

ahhhh oh well :ride:

  • NYMXer

Posted May 12, 2006 - 02:38 PM


I am running the same jetting w/ no issues at all. Did you try adjusting the fuel screw?

  • probracing1

Posted May 12, 2006 - 02:39 PM



I am similar situation altitude and temperature wise here in Utah...rode last weekend in the dez @ about 75 degrees and bike wasnt runnin very well.
I am going to throw in a 45 pilot (48 now)jet tonight for 2moro's ride.
I believe some other TT'ers have (or will) be downsizing their pilot jets too....

anybody else believe with the warmer temps we should try a smaller pilot?

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • l8r

Posted May 12, 2006 - 03:06 PM


I would say yes. Had a 48 in at one point, 90' temp, and it was too rich. I am running a 45 pilot, 165 main, 50 leakjet and a Boyesen QuickShot AP with great success.

I will say everybody needs to pay attention to the gas tank temp when it gets warmer (90's and up). I had fuel just about boil. Since that time, our weather has cooled off to around the 70' range and it has not been an issue. The Yams do not have the twin spar like the Suz and Honda and the aluminum frame seems to transfer heat much more efficiently than the others.

I have purchased heat Shields from for the carb and airbox along with insulation for the bottom of the tank from moose racing. I will update everyone as the temperature rise to the 90; mark.

  • RoughR1der

Posted May 12, 2006 - 06:15 PM


i just need to find a 45's a crap shoot at the dealers

  • xcape

Posted May 12, 2006 - 09:43 PM


I think the 48/170 myth is busted LOL 45/165 seems to work fine for most....trial and error I suppose

  • DPW

Posted May 13, 2006 - 06:43 AM


There is not one perfect jetting for every situation and bike. I have not rode for about a month, but the last time I rode is was around 85 degrees and the 48/170 ran fine for me.

I don't think it's too uncommon to have to re-jet for the summer and winter temperatures.

Related Content


Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

yz250x vs 450 4t comparisons (preferably desert riding) needed by JakeNorthrupYZ450F

Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 9 replies

Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride

Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies

Thinking about Yamaha 250... by Arctic Pride

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  491 replies

2016 YZ450 by CaptainKnobby

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.