Dear friends, Sorry for my poor Englisch (í'm a Dutch BSA and Triumph rider) but i have a question; my speedtwin loses oilpresurre when hot. If i start her the presurre rises up to 60/70 psi before the relaese valve start working. When hot during driving the presurre is about 15-20 psi. At idling speed it almost drops till 0 psi. The engine sounds well and runs beautifull; a first kick starter. I have fitted a new plunjerpump and a releasevalve from SRM engineering. I use SEA 40 in the summer. Is this normal?? Kind regards, Jacques Ruijssenaars

Hi...I have the same problem with a 1969 bsa. I changed from
40 to 50 wt oil with some reduced oil loss. I am getting a
small oil leak around my head gasket. I am comfident the
gasket was installed correctly.
Any ideas about stopping my leak.
Thanks

Have you retorqued your cylinder head recently, Might help the oil leak. When a copper gasket is used, I torque the head at least 3 times. 1. On installation 2. Warm the engine up well, maybe with a drive around the block,let the engine completely cool, retorque. 3. After about 50-100 miles and at least 3 or 4 warm-up and cool-down cycles, retorque 4. 500-600 miles, retorque

Good news and bad news. What you are experiencing is normal. Cold oil is much thicker and more resistant to flow than hot oil. When cold, oil pressure will normally be at or near the relief valve blow-off pressure. As the engine warms, oil pressure will reduce to some nominal value at operating speeds. At idle, the oil volume through the pump will be low and the pressure will be at its lowest value. The bad news is that oil pressure is directly related to the amount of wear in the plain bearings, connecting rods in your case. As wear occurs, the clearances increase and there is less resistance to oil flow with a subsequent reduction of pressure. Your info indicates that your rod bearing shells have significant wear and should be replaced. Ride gently and stay out of the mountains. The good news is that you have no rude noises and you have some measureable pressure at idle. You can probably count on several thousand more km out of this engine if you use a heavy oil such as SAE 50 and cheat with a viscosity enhancer such as STP or??? Keep the revs up (over 3000 RPM to ensure adequate oil flow) I would probably ride the machine gently until the oil pressure gets down to a consistant 15PSI The proper solution would be to replace the Rod shells and have the crankshaft journals reground to the next undersize. Keep the revs up though. If you ride at low engine RPM