Unleaded fuel set up

[Shades]

Hello all,
I have recently bought a late TZ125, year is '09 as far as I know.
I have always run my 250's (a 1990 and 1992) on Avgas without any problems,now my questions.....
I assume the 125 would be intended to run unleaded race fuel,which should not be a problem obtaining.
What are the techniques for 'reading' if the mixture etc is correct,I have been told that the unleaded fuel does not colour the plug and piston on the same way as Avgas?
What 'squish' clearance is best do you run similar to Avgas (which I run at 0.7mm)
Any other tips or advice much appreciated,thankyou
Ade

[Neiltziom]

Hi Adrian

What settings was the previous owner running? You don't get the same colour plug or piston crown but you can still use the same techniques by looking at electrode burn on the plug and the carbon build up on the piston. If the piston is dripping wet and clean its rich, completely dry its too lean , dry on the outside and black burn pattern covering appx 60/70% of the crown then its not too far away. However, the ignition, type of race fuel, oil etc will all introduce variables. It took me a while to get used to it without using a det counter but its fairly straightforward once you have a base set up to work from.

Neil

[Shades]

Hi Adrian

What settings was the previous owner running? You don't get the same colour plug or piston crown but you can still use the same techniques by looking at electrode burn on the plug and the carbon build up on the piston. If the piston is dripping wet and clean its rich, completely dry its too lean , dry on the outside and black burn pattern covering appx 60/70% of the crown then its not too far away. However, the ignition, type of race fuel, oil etc will all introduce variables. It took me a while to get used to it without using a det counter but its fairly straightforward once you have a base set up to work from.

Neil

Hi Neil,thankyou for the reply,the guy I bought it off did not give me any set up data,he was not racing it and I think he ran it as it arrived from Japan for a few trackdays.
What fuel would you recommend? I was told he ran it on 102 octane fuel he got from Germany.

[Neiltziom]

I have always used Hiperflo 250/300 , its not too pricey for a race fuel. Its around 102 octane.

[Shades]

Thankyou Neil.