Just bought a new 2012 YZ450F (pics)



23 replies to this topic
  • JakeNorthrupYZ450F

Posted June 03, 2015 - 09:42 PM

#21

What's the starting technique you guys were talking about? I've always just kept my hand off the throttle and kicked it like normal. The manual says it's bad to touch the throttle (not true?).

My bike usually starts in 3-4 kicks but would like to know any tricks for starting it before races.

Edited by JakeNorthrupYZ450F, June 03, 2015 - 11:14 PM.


  • grayracer513

Posted June 05, 2015 - 06:59 AM

#22

Push the kick starter up against compression, run the lever back to the top, and kick.  No throttle in most cases, but the EFI bikes may start slightly better if the throttle is opened very slightly.  Open it too far and it may kick back with a force you'd rather not experience.  BTW, opening the throttle beyond about 3/4 while starting puts the fuel injection in the "clear flood mode", shutting off fuel delivery so the incoming air can clear the excess fuel from the cylinders if it becomes gas fouled/flooded.  Another thing to remember is that there is no accelerator pump in EFI, so twisting the throttle with a dead engine will neither prime a cold engine nor flood a warm one.

 

Another trick, believe it or not, is to use the cold start knob, even while it's warm.  It's not a choke or any sort of enrichment device, only an air passage, much like the hot start on an FCR carb, and simply allows more air in, same as cracking the throttle a little bit.



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  • JakeNorthrupYZ450F

Posted June 05, 2015 - 07:17 PM

#23

Push the kick starter up against compression, run the lever back to the top, and kick. No throttle in most cases, but the EFI bikes may start slightly better if the throttle is opened very slightly. Open it too far and it may kick back with a force you'd rather not experience. BTW, opening the throttle beyond about 3/4 while starting puts the fuel injection in the "clear flood mode", shutting off fuel delivery so the incoming air can clear the excess fuel from the cylinders if it becomes gas fouled/flooded. Another thing to remember is that there is no accelerator pump in EFI, so twisting the throttle with a dead engine will neither prime a cold engine nor flood a warm one.

Another trick, believe it or not, is to use the cold start knob, even while it's warm. It's not a choke or any sort of enrichment device, only an air passage, much like the hot start on an FCR carb, and simply allows more air in, same as cracking the throttle a little bit.


Do you try to have your bike cold or warm for better starting?

  • grayracer513

Posted June 06, 2015 - 06:57 AM

#24

Always warmed up well.  Not "hot", just up to normal.







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