2011 Yamaha 450 WONT START! HELP!

28 replies to this topic
  • Coffey68

Posted June 05, 2011 - 12:54 PM


So after a hard crash yesterday at the track my bike wont start. I got up and picked the bike and it wouldnt start. So I let it cool down took it back home and still wouldnt start, we tried bump starting it and still wouldnt even kick over. So we checked the spark plug and it had plenty of spark. We even used starting fluid down the air box and it still wouldnt start. So we think it has to be something with the fuel pump and fuel delivery. Any IDEAS?

  • Chazmagnum

Posted June 05, 2011 - 01:03 PM


Use your tuner. It will tell you what's going on. If you don't have one, get one. It's about as important as your manual with this bike IMO.

  • Coffey68

Posted June 05, 2011 - 01:24 PM


ok i plugged in my gytr tuner and it didnt help like i said the bike wont start and my tuner only tells me the degrees of the motor and the runtime and idle speed so i dont know how that helps?

  • yz450fcranker

Posted June 05, 2011 - 01:33 PM


fill it up put it in gear try to pull it backwards a bit to free up the engine and when its free try kicking it over

  • RiverReaper

Posted June 05, 2011 - 02:59 PM


Check to see if the ecu mount is broken if it's tilted too much the bike will not run.

  • motoman808

Posted June 05, 2011 - 06:48 PM


ecu has a tilt sensor in it so the bike wont keep running if its on its side .yours is probably tweaked.

  • brentn

Posted June 05, 2011 - 08:14 PM


The tilt sensor in the ECU will show a code in the tuner when activated. Did you check the codes in the tuner?

I ask because you said you just plugged the tuner in and it didn't help. Sounds like you didn't even check for codes, you just literally plugged it in and said a hail mary, pulled it out and expected the bike to run? lol :ride:

  • Coffey68

Posted June 05, 2011 - 11:07 PM


no codes popped up or anything i searched the whole tuner but it sounds like im missing something here. we think its the tilt sensor to actually called lean angle sensor and if it is that a new ecu costs 400 bucks fml

  • RiverReaper

Posted June 05, 2011 - 11:33 PM


The sensor probably isn't broken but the mount or bolt broke so the ecu is just tilted, therefore thinking the bike is laid over.

  • Schpenxel

Posted June 06, 2011 - 06:28 AM


Does the tilt sensor cut spark or fuel or both? He said it had spark.. and was using starting fluid and it still didn't fire.

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  • Coffey68

Posted June 06, 2011 - 11:12 AM


the ecu wasnt tilted but we think the sensor inside is broke or something and theres no way of getting in there and fixing it. we might have to buy a whole new ecu which is expensive. if its not that we think it also could be something with fuel delivery. were gonna get my buddys 2010 yam 450 ecu and plug it in mine since there the same and see if thats the problem or not

  • rickallen124

Posted June 06, 2011 - 05:41 PM


So, you went into monitor and s/d on the tuner and no codes came up? If it's the angle sensor it should throw a code. My friends '10 is having issues as it will run anywhere from seconds to a minute and then shut off. No codes came up on the tuner so we think it might be a fuel filter/pump issue. It ran fine all day at the track saturday untill he came off the track and was putting around the pits. It died, he restarted rode a little further, it died again, he restarted again and it ran for about 5 seconds before it died again. Then it wouldn't start at all. After waiting 45 minutes it fired up and ran for a minute or so before dying again.

  • Coffey68

Posted June 06, 2011 - 07:47 PM


dang that sucks and yea no codes came up....i plugged my buddies ecu in and it started then quit right away and no it wont start again i put my ecu on and it started and quit so i have no clue im getting so frustrated

  • grayracer513

Posted June 06, 2011 - 08:42 PM


The diagnostic tool (not the tuner) will tell you very quickly where the trouble is. Either buy one or spend for a hour's shop time and get the answer.

But you might try loosening the gas cap once it first quits to see if it will stay running after that. If there's a way to connect a fuel pressure gauge, that would very likely tell you something too.

  • rickallen124

Posted June 12, 2011 - 03:33 PM


Have you unplugged the kill switch? My friends tiedowns moved on the kill switch side and damaged the cable although not visibly apparent. He unplugged it and the bike would run and as soon as he plugged it back in it would die.

  • powers450f

Posted June 12, 2011 - 08:52 PM


Where is the ecu located on the bike??? Thanks

  • Crawford43

Posted June 12, 2011 - 09:30 PM


If the bike is getting spark, and has decent compression and fuel, it will fire. Unplugging the kill swicth will usually fix a "no spark" condition after a wreck, but it has spark. Sounds like it isnt getting fuel, check your connections on your Injector then work back from there. It does sound like a ECU problem unfortunately.

  • Blake 888

Posted June 12, 2011 - 11:59 PM


maybe try checkin the condition of the fuel pump too?

  • grayracer513

Posted June 13, 2011 - 06:50 AM


Where is the ecu located on the bike??? Thanks

The manual tells you all of that. It's behind the number plate.

  • honda907

Posted June 13, 2011 - 06:02 PM


After a hard hit, the fuel pump inside the tank breaks. It can have a small crack in the plastic and pump gas, but once connected it will not pump with any pressure to the injector. A guy on here borrowed my tuner last year and this is what he found out after the tuner said everything was OK. Just a thought.

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