Just bough a Sherco 290. Dealer from Wales recommends 80:1 mix. By my maths and that of a search on google, that translates to 62.5ml per 5L. The 250ml mixing tube that came with the bike was marked at 80ml which he said was the mark he would recommend. This sounds a bit iffy to me. Surely the 62.5ml (5000ml/80 = 62.5ml) is they way to go?

Yours... confused!

You're correct in thinking that 80:1 is 62.5ml per 5l, I normally run 65ml per 5l as it's easier to work measure out- works out to be around 77:1

Don't get too hung up the exact ratio as long as it ends up being between 70-80:1

Thanks Tony27. I thought I was being daft. 65ml sounds 'safer as well as easier'. Cheers for reassuring.

Or just buy 4L of fuel, then the mix is a convenient 50ml for 80:1

Thanks Geodet. Even simpler!

I like that idea, hardly ever have to top up the tank during a trial

I printed out this and keep one on my shed wall and one in my toolbox:

I usually put about 70ml per 5 litres which is closer to 70:1 although there are blokes in my club which say they run 100:1 in their new Sherco's, but i would say that's not enough.

Cheers