Single cylinder engine idle speeds?

electronbee · Post by **electronbee** » Fri Aug 29, 2008 10:03 pm

Any ways, as I was looking through through the manual of my lowly 6HP Yanclone, I can not seem to find an actual idle speed. I know it was pretty much designed to run out at 3600 all the time.

The Yanmar manual points to 600RPM for their version of this engine.

Sound right?

Post by **Dan J** » Sat Aug 30, 2008 9:42 am

I honestly think the best thing you can aim for is whatever feels and sounds right on your bike.

I can wind my 10hp clone much lower down than it currently idles but then at idle the bike is virtually trying to pogo around my driveway - it also has an inclination to stall when the "throttle" is let go after a long run. So now it might sound a little high to some but no stalling and it idles very smoothly. I'd hazard a guess I'm higher than 600rpm.

Honestly - I wouldn't try and get it set at some arbitrary value in a manual, especially when a thousand little manufacturing differences can make such a different to the speeds the engine likes the most.

oldbmw · Post by **oldbmw** » Sat Aug 30, 2008 8:31 pm

Before you get too enthusiastic about lowering the idle rpm, you might want to check if the engine is running fast enough for teh fan and for sufficient oil pressure.

These industrial engines were never meant to idle.

Guess in the end it needs to be smooth enough for you to tolerate.

andrewaust · Post by **andrewaust** » Sun Aug 31, 2008 4:24 pm

I've seen somewhere that engine speeds for the yanclone needs to be around 1200rpm at the lower end of the scale, reason being include the points that oldbmw raised. If you run them to slow you'll glaze the bore, carbon up the cylinder from low temps and lower oil pressure to dangerous levels.

Keeping in mind this only includes single cylinder air cooled engines. I guess the Diahatsu's etc would idle around 700rpm, different engine all together though.

If I can find the information I'll paste up the link.

Cheers

Andrew

electronbee · Post by **electronbee** » Mon Sep 01, 2008 6:25 am

OK,

On the manual I have printed out I was reading the wrong block. There are different versions of the engine where the PTO can be either the crank or the camshaft.

For the PTO at the crank it is indeed 1200 RPM under a no-load condition.

Dan,

What is your engagement RPM? I was thinking going around 300RPM over idle for 1500 RPM or so engagement.

eb