Hey Dave

when you have the fuel tested its important that it has a dye in it to test with . What you may find a problem is that in Australia under Govt regulation there is a chemical added to all methanol which is a reactant to heat and sun light exposiure which is a safety indicator. When you get safe methanol from a fresh batch it is a very slightly blue colour. this is the indicator. If you pour a fresh batch of methanol and its not blue then it may have been exposed to heat prior to you receving it. When its fresh it has more chance of reacting to dyes in fuel and can fade in colour when exposed.

The Indicator has a PH of about 7 or 8 . Now depending on the dye used in the RC Fuel it may also detriorate the colour dye of the fuel added when not stored correctly. Typically it can fade in sunlight or if it goes from extreme cold to heat .. like if you store it in a fridge then take it to the track and leave it in 40 deg sun light. These extremes can fade the colour of fuel. typically the colouring is less than .03 % of the make up of a fuel . Mind you the fuel can fade while being transported. Even if its in a van or car in the back or in the boot of a car. this can kick off the process.

Wether a fuel has a dye in it or not makes absolutely no difference to its performance except in top end. Some Dyno runs with fuels with no dye have returned between 300 to 500 more rpm in the top end. This is typically good for Drag Racing or Boat / Plane applications.

There are plenty of fuel dyes avail for fuel, . The more you use the more chance you have of leaving discolouration inside the engine.. some people dont like it happening but its not always the dyes fault. Gulf Western make an awesome colour dye for this application. It is PH balanced and alkaline in make up. yes alkaline can react in nitromethane but only in lage or equal ratios .. when used in small quantities makes no diff.

Hope this helps with your testing

Cheers Sandy

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