Question about 2003 Yamaha YZ 250

3 Answers

Yamaha blaster runs but wont rev

Yamaha blaster runs at idle but wont rev or excellerate

Posted by on

  • lcjjcrouch Jun 21, 2009

    Ive already tried cleaning the carb, making sure the exhaust is clear twice, the motor also only runs if the throttle is all open, but won't rev. Idles with throttle all open. I'm stuck. Thanks for your comments.



3 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Master
  • 3,567 Answers

ALWAYS have a fire extinguisher on hand when working on carburetors.
Remove the water trap bowl at the bottom of the petcock, (gas valve). Is there any water or trash in the bowl? Drain a cup of gas from the tank. Is there any water or trash in the cup? Dump it, clean it and re-mount it, ( not all bikes have a water trap bowl ).

Drain the carburetor. There should be a screw on the lower side of the carb float bowl. Remove the screw then replace it after the fuel drains. Turn the gas back on and wait a minute for the carb to fill with gas. Install a new stock NGK spark plug and try to start the engine. If the bike doesn't start and run properly then shut off the gas and remove the carburetor from the engine.

Remove the float bowl and clean the entire carb with a spray carb cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the carb.
Before putting the slide back in the throat of the carb, move the clip on the jet needle one notch lower. Put the rest of the carb back together, clean the air filter and install the carb. Let the float bowl fill then start the engine. This process should get you back on the road.

yamaha blaster runs but wont rev - 849880b.gif Please rate this solution. Thanks!

Posted on Jun 21, 2009

  • 1 more comment 
  • tombones Jun 21, 2009

    The new information sort of changes what the answer would be. If the throttle is wide open and the bike just continues to idle, Then the slide is not moving upward or the main jet is plugged ( is the clip on the end of the jet needle? With the air cleaner removed, looking at the slide, what do you see when the throttle is turned?

  • tombones Jun 22, 2009

    Have you checked the float level? The adjusting tang may be out of position such that the fuel level is too low to reach the main jet.

  • luke lavoie
    luke lavoie Aug 30, 2014

    i have the same isue how do i jump the thoraddle over ride senser


  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 4 Answers

Did you possibly put throttle valve body on carb in backwards? if put in wrong it will idle but no excelleration. uncsrew and turn 180* then try again. it should go in and screw on easy with no forcing it down.

Posted on Nov 22, 2014

  • Level 1:

    An expert who has achieved level 1.

    New Friend:

    An expert that has 1 follower.

  • Contributor
  • 3 Answers

Yamaha dt200r starts for a second then dies what could cause this

Posted on May 20, 2014

1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Wont stay running/just rebuilt,,67mm all new

Hi there . These brothers know what to do. Trust me i feel your pain.


Oct 30, 2017 | Yamaha IR Blaster

1 Answer

Yamaha yzf r1 idles won't rev

Hi, Anonymous and the usual suspects are:
1. Throttle cables misaligned or misrouted.
2. Damaged or restricted fuel tank venting system.
3. Intake system air leak.
4. Vacuum piston malfunction.
5. Pinholes or torn diaphragm.
6. Accelerator pump leaking or no output.
7. Plugged bowl vent or overflow.
8. Fuel level in bowl too low.
9. Restricted fuel supply passages.
10. Plugged jets or passages.
11. Worn or damaged needle or needle jet.
12. The enrichner valve not seated or leaking.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
03 r1 idles rough wont rev
YZF600R Idle Problem Rev Problem
OEM parts for Yamaha

Btw, I’m available to help over the phone in case u need at

Dec 14, 2013 | Yamaha YZF-R1 Motorcycles

2 Answers

Yamaha blaster running problems

I have a blaster and if the parking brake is set it will do that

Mar 10, 2010 | Sport & Outdoor - Others

1 Answer

I can not get my yamaha blaster to idle have

Make sure you have no vacuum leaks and the idle screw is turn up. Then adjust the a/f ratio screw to highest idle, turn down the idle screw and repeat until a/f screw makes no change. At that point you set your idle speed.

Nov 12, 2009 | 2008 Yamaha YZF-R125

1 Answer

Trouble with 2004 blaster 200 idle

simple just turn the idle screw in 1/4 of a turn mate and its done 74197ac.jpg

Sep 10, 2009 | 2004 Yamaha YZ 250 F

1 Answer

Blaster idles but wont rev up

will it rev after taking air filter off?

May 23, 2009 | 2002 Yamaha Road Star Warrior

2 Answers

Yamaha yfs 200 blaster manual

You might find a free pdf service manual on this site, they have a ton of them.

or try your local library. Often guys will donate manuals to the library.

Please rate this solution. Thanks wikusnagel!

Apr 06, 2009 | 2003 Yamaha YZ 250

2 Answers

I have a 2004 yamaha blaster 200 i need a diagram or advice on the best way to take my carb. off, throttle cable from top of carb...

i can't seem to figure out why my 2004 blaster 200 won't idle properly. i cleaned the carb and replaced the spark plug. it revs fine but when it goes down to idle it just dies. any help?

Mar 01, 2009 | 2004 Yamaha YZ 125

2 Answers

1993 blaster wont stay running

try cleaning carb and see if the choke is hung up also make sure it has the right plug ngk b8es

Feb 22, 2009 | 2003 Yamaha YZ 250

Not finding what you are looking for?
2003 Yamaha YZ 250 Logo

6,753 people viewed this question

Ask a Question

Usually answered in minutes!

Top Yamaha Experts


Level 2 Expert

314 Answers


Level 3 Expert

1216 Answers

Steve Sweetleaf
Steve Sweetleaf

Level 3 Expert

1165 Answers

Are you a Yamaha Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides