Please help!

15 replies to this topic
  • reed_YZ426

Posted October 29, 2001 - 11:52 AM


i just tried starting my bike again and i'll tell you. it took me 15mins to get it started. right befor it started when i hit the compresion release and kicked down it made a real loud popping noise out of my silencer. after that it started right up. when i went back out there where the pipe goes into the engine it looked like it was almost RED hot. i could have just been seing things but it looked like it was red hot to me. anyone know whats going on with my bike? its never done this befor it usualy starts in 2kicks. now its over 20!

  • jaybird67k

Posted October 29, 2001 - 12:34 PM


It sounds like to me that you had excess fuel build up if it backfired like that, sometimes if you accidently get too much fuel you can hold the decompression and kick over a bunch to clear it.
When you do this it will backfire real loud just like a gunshot.
This would explain it starting after the may have cleared itself.
As far as why it would be getting too much fuel on start up, this could be a few things causing this.
Mine did this when it was not to old and it was wet fouling the plug, turned out to be a carbon build up from running dirty gas in a humid enviroment.
The carbon on the piston and combustion chamber collected moisture causing the plug to short and the fuel could'nt be burned.
Once it started, after a new plug, it would run fine until start up again and it would do it I'd kick my eye's out holding the decompression and it would backfire until all the fuel in the intake throat and cylinder was burned.
My fix happened to be race fuel, yours may be something different.

As far as the red hot header, if this is while its running this is normal.

Later, Jason

  • jaybird67k

Posted October 29, 2001 - 12:36 PM


[ October 29, 2001: Message edited by: jaybird67k ]

  • reed_YZ426

Posted October 29, 2001 - 05:01 PM


Thanks for the help, anyone else has an idea of what it could be?

  • DaveJ

Posted October 29, 2001 - 05:09 PM

#5 sounds like a flooding problem.

The more important issue is what is causing the flooding problem.

Can you describe how it runs once you get it going?

Di you always have the issue with the red pipe?

What sort of fuel are you using?

Did you make any mods? (ummm....take the carb apart?)

Move the TPS?

Take it to the dealer for a tune up?

There's a host of possibilities with this one, so the more info you can provide the sooner we can get to the bottom of this.

  • Adam

Posted October 29, 2001 - 05:18 PM


Has it been getting cold? if yes use the cold starter before the first kick.

  • reed_YZ426

Posted October 29, 2001 - 06:25 PM


after i get it started it runs just fine. ive never noticed my header pipe getting red hot but maybe i was either just seeing things or have never noticed it. i use the highest grade pump gas i can get. i havent taken it to the shop for a tune up ive had my bike for 3months its run perfectly fine always started up on 2kicks. and its completely stock i havent done any modifications to it.

and adam yes it has gotton cold. when you said use the cold starter what does that mean? use hot start button or choke? *confused*

  • yzernie

Posted October 29, 2001 - 07:06 PM


Hot=Hot Start

If there has drastic change in weather you may want to turn the fuel screw in and out to see where it works best. Usually cooler temps mean denser air which means leaner jetting.

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  • DOC

Posted October 29, 2001 - 11:10 PM


make sure no one goes into your garage at night and plays motocross games with your throttle. This has happened to me and i wasn't happy.

  • DaveJ

Posted October 30, 2001 - 08:07 AM


Here's a quick list of things to do.

Check the float shutoff,

Check or replace the plug,

Make sure that's there noting in the carb bowl but fuel.

After this, it could be TPS or CDI stuff, but I doubt it.


  • Adam

Posted October 30, 2001 - 04:29 PM


well the cold starter is the black choke lets say and it is used when you first use your bike during the day after being still for a while and the red choke is for after your bike is warme wich works if you wipe out and flood your bike.
when your bike is cold you probably notice when you kick its a little harder to turnover so when you start your bike alwasy try to kick as hard as you can, the harder you kick the sooner it will start

  • reed_YZ426

Posted October 31, 2001 - 07:28 PM


i want to thank those of you who have responded to my post. i greatly appriceate it. I'm getting a new plug tomorrow. I Was wondering should i change my Jetting since its getting a little cold outside? if so what would you suggest. anything else i should do? im sure my bike is flooding im not sure why though because its NEVER done this befor. i hate when i have to kick and kick and kick until my face turns blue with no luck :)

  • DaveJ

Posted November 01, 2001 - 08:23 AM



A bike can flood when it either gets too much gas or cannot burn off the amount of gas coming in, (bad or weak spark, poor timing of spark, bad or obnoxious fuel).

A simple plug change may do it. You may also have some water or dirt in the fuel bowl, (it's a stretch, but it can cause things to get a bit goofy).

Beyond this, check and adjust the air-mixture screw. This is the primary circuit for starting, so a 1/2 turn in may do wonders.

Lastly, I forgot to mention that you should inspect the rubber boots and seals around the hot and cold start valves.

Should you re-jet? Not yet. Sounds like you have something wrong, and you may want to fix that before you begin your fine tuning stage.


  • dan_Rekito

Posted November 09, 2001 - 05:30 PM


Your carb has an accelerator pump in it, so every time you twist the throttle it spurts in some gas .When I start mine I put my right hand on the handlebar NOT the throttle to avoid any twist when kicking over the beast. 2001 YZ426F 1996 XR650L

  • rjohn

Posted November 10, 2001 - 02:36 PM


I went through this w/ my WR and know what to do w/ my YZ. Pull in the comp. release and kick it a few times to flush it out. If nothing happens - change the plug. When cold I get it ready to kick then a blip of the throttle and she fires up.
The pipe glows cherry red at night which is normal.

  • reed_YZ426

Posted November 10, 2001 - 02:42 PM


I Noticed in this months issue of Motocross action it said as it gets colder to turn the fuel screw to give it more gas. would that maybe fix my problem as far as starting. i replaced my spark plug. and then i took it down to the shop to get that dang oil bolt removed. he had previously started it. didnt ask him if it started right up. i noticed though because my Fuel was on when i got home. after that it took i think 8 kicks to get it going. ill try again soon to see if it works any better

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