Forum bmwbike.com

I have just removed my R27 from a 2 year stint in storage. The bike was stored with an empty tank (rules).

Question: What maintenance should I perform prior to starting her up again? Oil change, flush the tank? Stupid question, what oil should I use with this bike?

Also, a general question. The engine was bult for leaded gas. Am I doing it any harm by using unleaded?

Thank you all in advance for any advice.

- Andrew

mine is about to get out after 20 years, did you get any good replies?

First I would make sure the piston is not stuck with rust. Very gently, use either the kickstarter or the rear wheel to revolve the crankshaft. If the crankshaft is stuck, or if there is a little resistance at first followed by snapping free, that might indicate that rust had formed on the cylinder walls. If so, starting the engine immediately could further damage the cylinders and rings and bearings, and contribute to the filling up of the oil slinger. If there is rust, I would remove the cylinder and have it honed clean.

Replace the battery. A battery that has been stored for two years will be no good. It might take a charge, but might not hold it for long.

Fill the tank with a gallon of gas and open the petcock to fill the carb, then close the petcock. It may take days for the gas to swell the dried seals of the petcock and carb, and they may leak until then.

Change all the fluids. Remove the valve covers and squirt some oil into the rocker shafts. Remove the spark plug and squirt some oil into the combustion chamber. Leave the spark plug out and use the kickstarter to spin the engine for a couple of minutes to get some oil pumped into the passages. This is a good time to check the valve adjustment.

Then replace valve covers and spark plug, and try to start the engine. Change the oil in the engine again after 100 miles.

over a long term running an engine on unleaded fuel that was meant for leaded fuel can cause upper cylinder damage. Leaded fuel helps keep the valves and piston cool because of the addatives in the fuel. If you intend to run the engine on unleaded fuel you may need to change your valves. Make more inquiries regarding this