leaded fuel residue?

9 replies to this topic
  • BRYNO426

Posted December 11, 2001 - 03:44 PM


whats up guys? i want to see if any of you have experienced a residue in the exhaust when using leaded fuel i am currently running VP MR2 fuel the scoot runs really crisp but i notice a greyish residue in the exhaust any ideas?

  • yzernie

Posted December 11, 2001 - 04:47 PM


What you are seeing is probably a slight carbon buildup which is normal. The reason it is gray is because of the lead in the race fuel. Unless the biuld up is really bad, no worries!!


  • Psycho426

Posted December 11, 2001 - 08:23 PM


I haven’t tried normal 93 leaded in my bike, I’ve been using unleaded ever since I got the bike.

Will the bike run better on leaded (normal not race gas)?
If so will I have to change my jetting if I want to try it?

  • jaybird67k

Posted December 12, 2001 - 02:35 AM


The grey build up is lead deposits, no big deal, just change your plug more often because it builds up on the plug really bad.
I just rebuilt mine after a year of running leaded race and was curious to see if the piston or combustion chamber had alot of build up, but it did not.

Later, Jason

  • yzernie

Posted December 12, 2001 - 09:35 AM


Originally posted by Psycho426:
I haven’t tried normal 93 leaded in my bike


You have 93 octane leaded??? I am jealous!! Leaded fuel is a good thing. The lead helps to lubricate/buffer the valve train. If the leaded gas is the same octane as the unleaded you are using you should not have to re-jet.


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  • Psycho426

Posted December 12, 2001 - 08:26 PM


Ernie - Yep, we are lucky aren't we(we don't have such strict pollution laws yet). We even have a fuel that is called 'Dual Fuel'(also 93), I'm not sure how it works but it's guaranteed for use in <font color="Navy">both leaded and unleaded petrol engines, neat isn't it :)

Thanx, I'll give the leaded a shot the weekendPosted Image

[ December 12, 2001: Message edited by: Psycho426 ]

  • Boit

Posted December 13, 2001 - 02:03 AM


I've also been using MR2 fuel with the slighty ashy grey residue. The throttle response with this fuel and proper jetting is phenomenal. C-12 worked well also but doesn't give the revability that MR2 does. At least that was my experience.

  • yzernie

Posted December 13, 2001 - 03:57 AM


Originally posted by Boit:
I've also been using MR2 fuel

What are they getting for a gallon of MR2 in La??? I can't find it for less than $9.00 a gallon here in So. Cal. :)


  • Boit

Posted December 14, 2001 - 12:49 PM


Ernie: $8 per gallon for MR2 in 5 gallon sealed pails. The pail makes a dandy pump gas container for the lawn mower once I've used the fuel up.

  • BRYNO426

Posted December 14, 2001 - 09:10 PM


Thanks for the input i just needed to easy my mind. and kudos to BK I did the mod a few nights ago and OH MY GOD!that has to be the best $.75 cents I have ever spent. :)

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