whats the best oil mix for evo 250 i used to run my rev 3 at 90ml to 5 litres so should i stick to the same?

You can do, i run 80ml to 5 litres, hope this helps

Hi Bruces670

In all the Evo's i have had i run them all at 75mls of Castrol TTS to 5 litres of super unleaded.

I have never had any problems. I have now changed to castrol XR77.

Cheers

75mls seems very lean what ratio does that work out at?

75 ml is 66:1 if mixed with 5 litres of fuel,this is the same as 1.5%, make sure it is fully synthetic oil.This is the specification in the manual. 4% mixture is listed for mineral oil.

whats the calculation to work out the percentage to actual mls added?

Hi Bruces670

If you look here - http://www.betamotor.com/system/attachments/0000/2212/Evo_2T_250-290_uk.pdf

It shows what PRW has said above.

As long as you use a good oil Like i mentioned before (castrol TTS or XR77) you will be fine to run

75mls to 5 litres of super unleaded.

On another point if you are riding in this cold weather that we are having at the moment you could change your spark plug for a NGK BR6ES or even a BR5ES. (it all helps) The std plug from the factory is a BR7ES.

Cheers

Edited December 19, 201015 yr by mobbster

thanks guys one more thing what is the little thing on the throttle cable for is it to take up the slack?

Hi Bruces670

In all the Evo's i have had i run them all at 75mls of Castrol TTS to 5 litres of super unleaded.

I have never had any problems. I have now changed to castrol XR77.

Cheers

Your post prompted me to look up "XR77". It appears that this is not offered in the US, as a search of the Castrol USA website turns up no match. All Google searches, resulting in news or prices for sale, appear to be UK based. Interesting side note, from one of the sites, indicates that XR77 is designed to leave more residue, so that "visual tuning" such as plug color, carbon in the cylinder, etc. are more easily seen. Not sure that this buildup, or residue, is something we desire in a trials engine. Can you shed any more light on XR77?

Hi DGShannon

The XR77 premix oil is a more advanced fully synthetic oil than the castrol TTS oil hence it is a little more expensive.

It is on a par with castrol A747 which was designed for engines running leaded petrol /av gas etc

The XR77 is made for use with unleaded fuel. (however i know people who swear by using A747 with unleaded fuel and it still works perfectly)

There is no more residue build up than using any other fully synthetic oil.(not like the old castrol R30 etc)

The XR77 just leaves a better indication on the plug/piston crown if the engine is running lean or rich.

Cheers