Petrol Mix

[samo]

Hello, I just read on Betatrialuk that we should use Semi Synthtetic oil for Petrol mix.

I use TTS and have every year a lot of Carbon on piston and Cylinder head..maybe Semy Sint. is beter in this direction?

Samo

[tonybroad]

ask different people you'll get different answers, you'll always get carbon build up cos trials engines are pretty under stressed and well fuelled which is why we can get away with mixes down to 80:1, you may just be running rich so it wouldn't matter what oil you used

speaking to a guy at work who is a lecturer in tribology, fully synthetics are generally superior to semi synthetics for burn and lubrication but then a good semi synthetic can match a poor fully synthetic, castor based oils burn worst and vary because they use a natural crop

he compared fully synthetics to the best whisky, semis to best whisky with a splash of water and castor oils to some good ol' moonshine, they all do the job but are brewed slightly differently

but that doesn't make any of them necessarily inferior, they all work

i use putolene MX5 fully synthetic for my trials bike and also in a yamaha 250 race engine i've run for years and i see no reason to change

just my opinion

[kasob1964]

Hi,

I use Castrol TTS at 80:1 on a Beta Rev 3 250, so far so good. I was running it at 50:1 like my enduro bike to keep refueling simple but I was running low on fuel while practicing and borrowed some at 80:1 and noticed an obvious difference in power/response. I guess that if you run more oil than recommended you should change the jetting. Good luck!

[samo]

Thanks guys for the answers;) What about Semy-Sintetic, Beta recomended...?