Forum bmwbike.com

I am driving a 1966 BMW R27. Normally I use leaded super, but next year they will stop selling l
leaded petrol in Switzerland.
Does anybody have experience with unleaded fuel?

We have been using unleaded gas for many years in the USA. If you ride your R27 only a little, and gently, the old valves should last a long time. If you put a lot of miles on your R27 and run it hard, valve seat recession may occur. When you begin using unleaded gas, you should check the valve adjustment more frequently.

For awhile, lead additives were sold in the US to mix with the gas, but they could be absorbed through the skin, and are now illegal. There are also lead substitutes, but it is doubtful whether they work. And all additives are a problem to carry.

When I restored my 1966 R27 recently, I used valves, seats and guides designed for use with lead-free gas.

You can buy valves for unleaded gasoline (for example from Mark) and install them. You also have to change the valve guides and seats, but the whole job should not cost you more then about 200 SFR.

I had the operation done on my R25/3 here in Manila, and it's running beatifully now on unleaded. Here they are also talking about phasing out leaded gas next year- right now both leaded and unleaded is available as in most other countries, but I find it hard to believe that they will stop selling it next year because there are so many old clunkers on Manila's streets which would not run on unleaded.

Christian

In Germany,in the 50", nearly no petrol was leaded.ARAL had only unleaded petrol until (about)62.There are so many opinions about that theme, I think it was only a kind of faith. I used,since it was available(about1980) only unleaded fuel for my R67/2sidecar+25/2.
I driving 20000km every year to work + holidays with them.Driving slowly isn"t possible in our days, it"s more a race (especially for that 12 hp cycle). I check my valveseats every year,no,really no, problems.
If you check your valveclearance every 1500 km,you will see early enough if the clearance(inspite of my words) disappeared and so you have time enough to spent your money for unleaded valves etc.. Rolf Gehrke Hamburg

Use super-plus and additive