2015 YZ450F hard starting in the woods. FI tool to set C1 ?


8 replies to this topic
  • MidlifeCrisisGuy

Posted September 21, 2015 - 10:31 AM

#1

My friend has a 2015 YZ450F.  The engine is totally stock.   If he stalls it in the woods, it is very hard to start.  It almost can't be started in gear.  Once in a while it backfires when kicked.

 

I have a fuel injected 2012 WR450F.  It kick starts very well, even if stalled.  I have set the C1 parameter with the FI tool so that it is richer at idle.

 

Does the FI tool trick work on the FI YZ450Fs ?

 

What can be done to make my friends YZ450F start easier ?



  • grayracer513

Posted September 21, 2015 - 12:55 PM

#2

To start with, take it out of gear.  Sorry, but they'll only start in gear during that brief period while the clutch is completely perfect.  For the other 95% of the bike's life, it's basically a waste of time to try it.

 

Secondly, the YZ seems to like either having the throttle cracked open slightly while starting, or using the "cold start" knob instead.  All that does on a warm engine is to raise the idle speed during the start by letting in more air.  It only makes it richer when the engine is cold. 

 

Raising the idle speed helps as well in some cases.

 

Richening the idle mixture (increasing CO) might help the YZ as it did the WR also.  Don't know for certain.



  • MidlifeCrisisGuy

Posted September 22, 2015 - 08:12 AM

#3

To start with, take it out of gear.  Sorry, but they'll only start in gear during that brief period while the clutch is completely perfect.  For the other 95% of the bike's life, it's basically a waste of time to try it.

 

Why is this ?  My WR easily kick starts in gear.  I'm using a Magura hydraulic clutch lever.  If you stall the bike in a bad situation, it is not practical to take it out of gear.  And it's a pain to do.

 

 

Secondly, the YZ seems to like either having the throttle cracked open slightly while starting, or using the "cold start" knob instead.  All that does on a warm engine is to raise the idle speed during the start by letting in more air.  It only makes it richer when the engine is cold.

 

Ditto with my WR.   But even doing this on the YZ doesn't make it start. 

 


 


 

Raising the idle speed helps as well in some cases.

 

Richening the idle mixture (increasing CO) might help the YZ as it did the WR also.  Don't know for certain.

 

We did raise the idle speed and it did help.  Not sure if it slipped down again or just needs to be higher.

 

Does the FI tool work on the YZ450F ?  Is C1 the idle mixture parameter ?

 

Thanks for your reply.



  • MidlifeCrisisGuy

Posted September 25, 2015 - 11:06 AM

#4

Anyone else have ideas or tips ?



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  • Krannie McKranface

Posted September 25, 2015 - 07:23 PM

#5

There is an FI analyzer that the WR guys use to alter CO level at idle.

 

Look in the WR450 forum



  • MidlifeCrisisGuy

Posted September 28, 2015 - 08:16 AM

#6

There is an FI analyzer that the WR guys use to alter CO level at idle.

 

Look in the WR450 forum

 

I've got one.



  • WouldsAssassin

Posted September 28, 2015 - 04:17 PM

#7

My 11 can be difficult to start or it is a one kick affair. I never know which way it's going to be when I stall it or shut it down. When I stop, I try to do so on the top of a hill or a descent.

Absolutely needs to be in neutral. Raising the idle may have made the biggest improvement in starting. Adding the GYTR offroad flywheel made it easier to start too.

Also, there is a video from Yamaha about starting the FI bikes. Watch it and take notes. Of particular importance is not kicking the bike too hard. If you kick too hard the engine speed will be too high and will override the decompression springs and make it harder to start. I'm 6'4 and squat 300+# weekly and really feel like I'm resting my foot on the kicker when I start it. It still starts inconsistently but it is better than before when I used to kick it like it cheated at poker.

I'd like to try making changes electronically. If you do, please let us know what you did.

  • Gaz929

Posted October 01, 2015 - 05:12 AM

#8

There's too much drag on the clutch for it to start in gear so your wasting your time, now and then you might be lucky and it fires up but 99% of the time it will not fire up in gear.

Edited by Gaz929, October 01, 2015 - 05:13 AM.


  • torkd14

Posted October 01, 2015 - 06:38 PM

#9

To be honest your buddy just has to learn how the bike likes to be started. My '14 likes two fast kicks and she's purring. My 2011 likes the throttle cracked with about 4 quick kicks. They have a mind of their own, I'm tellin ya!!





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