hard starting cold or hot

I bought a 2014 wr 450  brand new , starts like crap , I had all the mods done , the air box , the comp ecu , re - mapped , and new spark plug , I start it by the book , its still starts like crap.....  help ??

I had the same problem. Check your valves. I found that my exhaust valves were on the tight side. Have you changed the jetting on the bike?

Edited by woody678

I had the same problem. Check your valves. I found that my exhaust valves were on the tight side. Have you changed the jetting on the bike?

No jetting on FI bikes.

2014 WRR-Totalled

2012 WR450F-Stolen

2012 WR450F-Third bikes the charm.

Oh yea forgot about that.

Valve adjustment for sure, but it could be several things.

 

Are you pulling out on the enrichment knob when starting?

Have you turned the knob counterclockwise a couple of clicks yet?

Do you crack the throttle for a moment while pressing the starter?

 

Now, does the bike have a fuel filter inside the tank? If not, then the PO has been pouring dirt into the FI system, which you need to stop from occuring.

 

Visually inspect the tank with a flashlight for debris, and even better, pour out the gas from the top through a filter so you can see if the tank is messed up or not.

 

Then, you need to pull the pump and filter and inspect them. The fliter can be cleaned/replaced

 

Now you need to get an in-tank filter to keep this from happening again.

 

...and the plug. It could need replacing.

I just reread you post; you are the PO!

 

The motor will be ocassionally hard starting for the first 5 hours or so

My starting issues were related to the stock ECU. But you've already replaced yours.

When you say starts like crap are we talking kick start, electric start, idling , w/throttle, w/o throttle?

In the past I've had to crank the engine over 4-5 times wide open throttle, then release the throttle and it fired right up first hit.

2014 WRR-Totalled

2012 WR450F-Stolen

2012 WR450F-Third bikes the charm.

guys thanks for getting back , snake river Yamaha is working on it , they said when they put in the new ecu chip  they probably richened it up to much . you guys know the drill from those folks, they hem and haw really not giving you a direct answer , as soon as they REALLY fix the problem , I will post the specifics , and I will bring up the issues does the tank have a filter ect , hey maybe its bad gas !!!!!!!!!

I just reread you post; you are the PO!

 

The motor will be ocassionally hard starting for the first 5 hours or so

Can you explain the first 5 hours part.  I have 4.6 hours on a yz450 and starting sucks 

guys thanks for getting back , snake river Yamaha is working on it , they said when they put in the new ecu chip they probably richened it up to much . you guys know the drill from those folks, they hem and haw really not giving you a direct answer , as soon as they REALLY fix the problem , I will post the specifics , and I will bring up the issues does the tank have a filter ect , hey maybe its bad gas !!!!!!!!!

The ECU tuning can't affect idle starting if I'm not mistaken.

2014 WRR-Totalled

2012 WR450F-Stolen

2012 WR450F-Third bikes the charm.

Can you explain the first 5 hours part. I have 4.6 hours on a yz450 and starting sucks

I would assume its because clearances for the rotating assembly are still tight. Once everything has a chance to wear a little things loosen up allowing easier starts.

2014 WRR-Totalled

2012 WR450F-Stolen

2012 WR450F-Third bikes the charm.

When mines cold I kick it twice, and any other time during that ride it will start on the button. However it will not start in gear only neutral!

When mines cold I kick it twice, and any other time during that ride it will start on the button. However it will not start in gear only neutral!

Mine did that too when I got it, its a 06 model. When I took the headlight of to change the bulb I found a connector that wasn't plugged in, it was the clutch-lever-connector-switch-thingy, i plugged that in and now i can start it with the clutch disengaged in every gear.

It's really handy cause i hate searching neutral with my big riding boots... Feel = zero in those things

There is a very long winded post for these FI cycles, and their penchant for hard starting. It's a recent thread too, you can search for it.

 

Krannie's right, hang in there and wait for the motor to break in just a little.

 

You're gonna want to set the CO level. For that, you'll need the Diagnostic tool (it's a one-time setup), and again, wait a few more op hours before doing this.

 

I dont know what kind of riding you do (fast 'n rip, or slow woods crawler), but you might have to think about what kind of FI map to use, to prevent boil-over or "red header" conditions.  There's threads for this, too.  Get resolved to begin a bit of reading here.

 

There's a fuel filter in the gas tank, but it's embedded in the fuel pump and not separately replaceable.  That is, to replace  the filter, you replace the pump.  So far, no one has thought of a way to replace just the filter portion, or how to install an after-market filter into the system without causing other problems (on the high pressure side output of the pump, exiting the tank).

they did it !!!! I got my bike out of the shop .  they did a complete leak down test , checked the valves , the mapping , this was done by the corporate guys at the factory , he rides a wr . the problem WAS found in the efi .....  they adjusted the sensor for starting , it puts the right or wrong amount of gas into the chamber .... there was no internal problems .    it was simply an electronic tweak ..  I went riding with my daughter yesterday ,  I put my bike to the test ,  hills , sand , jumps , hardpack ect ,,   its a rocket with tires .  remember I live in Idaho , its starting to get cold ,  I left it in my garage all night , the true test came when I got up for work at 6.30 am ,,   I went to my garage jumped on ,,,,,,,,,  AND 2 kicks later my wr came to life  ,,,,,,, it brought tears to my eyes ,,,     till we talk again     eat some dirt for me  .......................

That was the CO adjustment that fixed your problem. Most of us here have had it done it's a must do for the WR's to work right.

There's a fuel filter in the gas tank, but it's embedded in the fuel pump and not separately replaceable.  That is, to replace  the filter, you replace the pump.  So far, no one has thought of a way to replace just the filter portion, or how to install an after-market filter into the system without causing other problems (on the high pressure side output of the pump, exiting the tank).

 

 

The WRs use the same fuel pump as the FI YZs.  Several YZ owners have pulled their fuel pumps, disassembled them and cleaned the filter.  You can find details in the YZ forum.

 

The Yamaha fuel injection system is similar to the KTM FI system.  Same throttle body and injector, similar pressures.    Some KTM bikes use an external filter.  I suspect it could be incorporated into the WR FI system.

Edited by MidlifeCrisisGuy

The WRs use the same fuel pump as the FI YZs.  Several YZ owners have pulled their fuel pumps, disassembled them and cleaned the filter.  You can find details in the YZ forum.

 

The Yamaha fuel injection system is similar to the KTM FI system.  Same throttle body and injector, similar pressures.    Some KTM bikes use an external filter.  I suspect it could be incorporated into the WR FI system.

 

OK that's great!

 

I don't inhabit that land... Would you please provide a thread pointer where they describe what they do / how they do it?

 

I've been on a lot of different forums that discussed this issue (I own many different models of FI cycles).  The hard part about what you suggest is, getting the fuel pump reassembled and whole while still providing a *safe* pump.  I don't mess with fuel components if I cant sort out the safety factors to my satisfaction.

 

It's the reassembly adhesive that is the sticking point (oh jeez) for me.  How to get that pump resealed to a safe spec again with absolutely no possibility of leaking?

 

Tell me how, please, I would *love* to save $100's in not buying new fuel pumps.

Don't they use o-rings for that assembly?

OK that's great!

 

I don't inhabit that land... Would you please provide a thread pointer where they describe what they do / how they do it?

 

I've been on a lot of different forums that discussed this issue (I own many different models of FI cycles).  The hard part about what you suggest is, getting the fuel pump reassembled and whole while still providing a *safe* pump.  I don't mess with fuel components if I cant sort out the safety factors to my satisfaction.

 

It's the reassembly adhesive that is the sticking point (oh jeez) for me.  How to get that pump resealed to a safe spec again with absolutely no possibility of leaking?

 

Tell me how, please, I would *love* to save $100's in not buying new fuel pumps.

 

http://www.thumpertalk.com/topic/1017998-2010-yz450-bogs-after-15-minutes/#entry10702600

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