Update on 2010 Starting Problems when HOT


7 replies to this topic
  • MXR176

Posted September 14, 2010 - 05:53 PM

#1

Ok I posted awhile back about my 2010 450 having problems starting after it was hot. Like there was times it would take 10-20 kicks to get it started. It also had a little blurber on the bottom. Long story short I was mixing Sunoco 110 and 91 Octand pump gas. I drained the tank out and started over with fresh 91 octane, started like always on 2nd kick when cold. First thing I noticed was the little blurble was gone and it was rediculous responsive again. Went and rode it and power felt a little better then it had. Rode for 20 mins came in from riding sat for 10 seconds and kicked it. It started on the 3rd kick. It had never done this with the mixed gas and I was getting frustrated. Anyways these new FI BIKES DON'T NEED RACE GAS. Im old school and it was always in my head for the longest time that you need race gas. Yes you do on a 2 stroke, the new EFI bikes DONT!!!! Just passing on what I found out with a little testing. Also the thing runs cooler to not running the race gas also. :ride:

  • grayracer513

Posted September 14, 2010 - 06:27 PM

#2

The Sunoco you were running was a pump gas, right? That means it was blended for old school muscle cars with high compression V8's, carburetors, and long intake paths from the carb to the combustion chamber. Nothing at all like a four stroke motorcycle. It wasn't the octane, it was the vapor rate.

Racing fuels blended by people like VP expressly for modern four-strokes do offer power advantages through better fuel chemistry, but they are also blended to match the way the engine is made.

  • brentn

Posted September 14, 2010 - 07:00 PM

#3

Mine won't start hot unless you crack the throttle just a little bit, sometimes 1/4 then she goes. Otherwise you can kick all you want, nothin is going to happen.

  • MXR176

Posted September 15, 2010 - 03:23 AM

#4

The Sunoco you were running was a pump gas, right? That means it was blended for old school muscle cars with high compression V8's, carburetors, and long intake paths from the carb to the combustion chamber. Nothing at all like a four stroke motorcycle. It wasn't the octane, it was the vapor rate.

Racing fuels blended by people like VP expressly for modern four-strokes do offer power advantages through better fuel chemistry, but they are also blended to match the way the engine is made.


Nope have the barrel sitting here, its equivlant to VP C12 and I got it for cheaper. Its going in the smoker now. On all my 250fs I ran U4, U4.2, and MRPRO4.1. I know what your talking on specialty fuels and yes they do work. But I quit using them when I quit trying to make the nationals and supercrosses. Brent N I dont even have to crack my anymore since switching back either.

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  • brentn

Posted September 15, 2010 - 08:10 AM

#5

I'm using 91 octane pump gas, nothing special at all here. I have to crack my throttle but you don't... :ride:

  • MXR176

Posted September 15, 2010 - 01:12 PM

#6

No I dont! I have the less hit map in it to, I have my idle turned up a little from stock though to. Which might be why I dont have to crack it.

  • nickeenoo

Posted September 16, 2010 - 07:31 AM

#7

Not really sure why you think you can't use pump gas in a two stroke? Of every two stroke rider I know, not one uses pump gas and not one has any problems.

  • grayracer513

Posted September 16, 2010 - 08:19 AM

#8

Not really sure why you think you can't use pump gas in a two stroke? Of every two stroke rider I know, not one uses pump gas and not one has any problems.

Contradictory.

(also off topic)





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