[Arizoni]

My new fuel injected G5's idle speed is higher than I think it should be.

I'm not sure if this was intentionally done by the factory because the engine needed to go thru its break in or not but now that it has over 500 miles on it I would like to slow it down a bit.

The Service Manual says the speed should be 1050 +/- 200 RPM and the adjustment is made by turning the large slotted brass screw on top of the throttle body clockwise to slow the engine down.

At the moment I really don't know what the idle speed is but it seems to be about the same as the engine speed in 5th gear at 30 MPH.  According to my calculations that is a little less than 1600 RPM.  Of course this is just going by ear and that is no  way to really know what the true speed is.

From my days before computers took over the control of automobiles engines I have a Tach/Dwell meter which was made to be used with the old fashioned points ignition system.

Is it possible to hook this Tach/Dwell meter  to my G5's coil without toasting the computer?  If not, is there some sort of dedicated connection where it could be used?

About the only other way I know of to determine the actual RPM is to use a tachometer with a inductive coil pickup and at the moment, I don't have one.

What do you guys use to set your idle speed on these EFI machines?  Any suggestions at all will be appreciated.

Jim

[singhg5]

Jim:

Have a look at this video, - one of the first ones I had made long time ago. You can hear the sound and see the RPM reading on the tach.  Just by listening, you may be able to match your bike's idle to it - if you don't have a tach.

http://www.youtube.com/watch?v=w51XKoubABI

[Ducati Scotty]

You should be able to use your old tach/dwell meter by clipping to the low voltage lines of the ignition coil.  Whether it's points or electronics making and breaking the circuit shouldn't matter.

I just checked my bike the other day and it's running around 1500, spec is 1000 +-100RPM.  I'm leaving it where is is for now.  It doesn't seem too fast and helps me not to stall when it's going through the first 20 minutes or so of warmup when the idle tends to vary more.

Scott

[Arizoni]

singhg5:  Thanks for the video.  Based on the sound you recorded I would guess my idle speed was similar to Ducati Scotty's, a bit fast.

Because I live in Phoenix where it often gets into the 105-110*F temperatures and quite a bit of my riding is in the city with all of its traffic lights I really don't want a real fast idle speed.

What I would really like is a nice Thump Thump Thump sound like the singles with the old style compression release lever can run at but with the auto decompression device in the EFI engines I know that can't be done.
Anyway, based on the video's sound I reduced the speed a bit. 
I'll post if it increases the tendency to die at the traffic lights but for now it is putting away with a nice steady beat.

Thanks again
Jim

[Ducati Scotty]

We should mention that several people have noted the idle seems to go up a bit as the engine breaks in.  I guess it has a little less friction once it settles in.

Scott

[barenekd]

When I had my bike dynoed, my buddy who did the dyno test, reset the mixture to the proper ratio, but it still idled quite fast when i pulled up to a light. It would slow down after a time to something more reasonable after a time, or I would slip the clutch a little to get it to slow down. I put the NGK BPR6es as mentioned on some of these posts and that took care of the idle problem. I don't know exactly how fast it's idling as I haven't hooked the tach to it yet, but it is acceptable now.
Bare

[Okie Enfield]

My bike was suffering from cold-start-itus since I first purchased it. When starting up it would die a few times, sometimes as many as 5 or 6 before settling in. Once warmed the idle seem more or less fine and only died a few times at stops. With 1500 miles now the bikes idle has increased slightly and no longer ever dies at stops but still had the OEM plug and the cold-start-itus had not gotten any better. During my last service I had the NGK NGK BPR6es installed and the oil changed. The cold-start-itus has now disappeared completely. My C5 fires and stays running with the first kick of the electric foot button  and does not seem to mind at all that it is cold. However, now the idle does feel a bit higher. I may decrease the idle later if it continues to get faster but right now seem more or less Okie Dokie! 

[Marrtyn]

After a good run the other day, I noticed that when I pulled up, and stood the bike on the centre stand, (still with engine running), that the idle speed tendered to be variable.

The revs for about 3-4 secs increased then they slowed down for about the same time, This cycle continued for a good while,- untill I switched the engine off.

I dont know wether or not this is due to the Ecu sorting itself out, from a hot engine (from the run), to an engine which is now cooling, (be it slowly)!!

[barenekd]

Have you changed the plug? Best $3.50 you can spend!
Bare

[Ducati Scotty]

Martyn, it's normal.  With the way our EFI works if the engine is at a steady speed it's constantly cycling back and forth from lean to rich and back again.  You might be able to feel/hear it if you stay at a steady cruise speed.  Mine is hardly noticeable when dead cold, very pronounced during the first 20-30 minutes of riding while it gets to normal operating temperature, and then subtle once it's fully warm.

Scott

[Maturin]

Generally it's better to set the idle a little too fast, rather than too low. The main bearings of a single like that a lot better.