7 replies to this topic
  • 116CJ

Posted June 27, 2006 - 05:31 PM


i have read the jetting thread and i did a search. I have an 06 450 and when its idling and i wack the throttle it bogs or hesitates then hits. Is this common? it seems to get better as i move out the air screw but should it be out 3 1/4-1/2 turns out? I have tried the 170 main, 168 main and 165 and i have tried the 45 pilot with the 168 and 170. now i dont notice it much while ridding but if your sitting there idling and just wack it, it does it which leads me to think something needs an adjustment. or is this what the boysen quick shot fixes. I am new to 4 strokes so any help is apreciated.

  • WFOracer

Posted June 27, 2006 - 05:48 PM


I have the 06 as well and swapped out the stock jetting. I run about 800' elevation - 70-90 degrees

I went with a 48 pilot and run either a 170 or 165 main, depending on temp. My fuel screw is usually around 2 turns out, give or take a 1/4 turn.

  • grayracer513

Posted June 27, 2006 - 05:58 PM


First, the bike needs a bigger pilot. I run a 45. Go with a 45-48.

Second, what it does in neutral is meaningless. the timing and advance curve are different in neutral than once in gear.

Third, what everyone needs to understand about 4-strokes is that even with an accelerator pump and perfect jetting, they can be shut down by snapping the throttle open hard enough at the spec'd idle speed in most cases. Attempting to get rid of that requires going beyond the accel pump and jetting levels that are needed for good performance. You should, instead, learn to roll the throttle open rather than snap it.

This technique involves opening the throttle more slowly at first, and progressively faster as the engine responds. Once you learn it, anyone listening to the bike will think you're simply flipping the throttle. I can make any of mine sound as if they exploded off idle right to 7000 without giving it a thought, and the important thing to realize is that the "bog" never shows up when you're actually riding.

  • 116CJ

Posted June 27, 2006 - 06:04 PM


cool thanks guys, the warmer the tempertature the leaner the jet? like say 90 run the 165 and 70 run a 170? im going try out the 48 pilot. has anyone had to change the needle possition?

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted June 27, 2006 - 06:39 PM


Not me.

  • yamahacrazy_310

Posted June 27, 2006 - 07:36 PM


cool thanks guys, the warmer the tempertature the leaner the jet? like say 90 run the 165 and 70 run a 170? im going try out the 48 pilot. has anyone had to change the needle possition?

I run the 170 and it runs perfect in wormer temperatures.

  • SureBlue

Posted June 27, 2006 - 10:50 PM


Raise the needle one clip too, it took away the slight bog and surging on mine. And think of it: if you need a larger pilot and a larger main, why would you not need to give more fuel at midrange = raise the needle?

  • mankind810

Posted June 28, 2006 - 01:25 AM


Grayracer is on the money about bog.
This man is very good with his advice and his posts should always be consisdered. :excuseme:

Related Content


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

YZ450F 03 Sparks driving me crazy by SirAttard

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 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

Snake pit oct 30th by The Anvil

Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 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.