Anyone running VP MR1 fuel.

3 replies to this topic
  • doubledee

Posted June 15, 2005 - 07:24 PM


I do not want to start a useless race gas thread.

I'm wondering if anyone is having good results specifically with VP MR1 without re-jetting? :) :) If you are you already know the properties of this race fuel. I want to leave my current jetting alone for a few reasons and it's already jetted perfectly for my mods. I've run other fuels etc. I'm familiar with running different race fuels in my GSX-R and understand for max perf you need to tune it etc. I ran a search on MR1 but most of the info was 2+ years old.


  • gonzo

Posted June 16, 2005 - 08:36 AM


It's probably old because of Ultimate 4. It's pretty much the same thing as MR1 but cheaper and everyone has been running that. Both are oxygenated so you'll have to rejet. I've tried running U4 without rejetting and it sucked. Just record what your jetting settings are and when your not running race fuel just go back to the settings. I wouldnt bother with MR1 unless you can get it cheaper. The U4 is the way to go. Just bump all your jetting up 1. Pilot needle main and your good for U4.

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  • doubledee

Posted June 16, 2005 - 01:28 PM


I was "told" and the specs on the MR1 fuel seem to make sense that because MR1 has a lower oxy and oct levels than U4 you do not need to alter jetting. I guess it's like 90 mon so the octane is relatively low for race gas. I've heard that it really does make a huge difference. I had a trusted source tell me he runs it in his race bike and feels a big increase at the throttle/ wheel. I guess it's also is not as harsh on rubber componets.

Someone else said the increased cost over U4 is worth the fact that you can leave it in the bikes but really how hard is it to flush w/ pump. I guess U4 can "crystallize" in the carb. I'm no chemist but know that my dirt bike hates the RTEC ProV1 fuel I run in my roadrace bike so I need to experiment here.

I'm just wanting to be lazy when I ride dirt. I ride trails all over. Soooo most times I'm content with pump but on occasions I'd like to have a "boost" when riding fast trails with faster riders on faster bikes than mine. :)

  • DigilubeJay

Posted June 19, 2005 - 11:00 AM


To say that your bike is jetted perfectly for your mods is a mis-statement. Unless of course your weather never changes...which it does.
The need for jetting changes comes with the simple change of atmosperic conditions, like temp, humidity, and altitude.
This changes ever single day, in every single location, and in most cases can change from morning to evening.
If you aren't willing to change jetting , then you have no business worrying about exotic fuels.

Many think they can simply go to the local gas station and fill er up with Turbo Blue and have a fire breathing beast...but they don't, and they are only fooling themsleves.
However, they will swear to it.

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