Hitchcocks Forum

Colleagues, I've noticed that the tickover on my new B5 isn't completely steady or reliable. When it is ticking over, if I listen carefully I can hear that the idle speed varies very slightly, and tends to get slower if it is left idling for a long-ish time (like at slow traffic lights). When I first got the bike I thought the idle speed was far too fast, but apparently the EFi engine is supposed to idle at 1050 rpm. I hate it that fast, so I've slowed it down to about 850 using the large brass screw on top of the throttle body. Much below that, though, and it is prone to stopping. I should emphasise that the engine only has 100 miles on it, although this particular characteristic hasn't changed over that 100 miles. What are your experiences?

I'm on my second EFI and they've both done it.

Thack, I have had my EFI since they were first released. They do that. Idle is NOT stable. You will find that if you set the idle too low, it WILL cut out when waiting at lights from time to time, and this will depend on the weather - it'll cut out more on cold and wet days. Set your idle where you want it, but then turn it up just a tad. Also, gentle progressive throttle on take off... the injection system is prone to flooding the engine when taking off from a long idle period if you hit the throttle too hard. I am talking about the first 0.5 seconds of throttle here though... the first 'blap' so to speak




Is yours lecky start? I noticed far better idle stability (and far less stalling) after I removed my sprag clutch - not suggesting you should do this at all!!!! BUT I reckon the sprag assembly drags very slightly, causing the starter motor to slightly load the engine on tickover.

IDLE???



mine doesn't idle!



when waiting at junctions, the engine does the 'two step'.



I had assumed that there was something sticking with the throttle cable as Thunderbolt is very consistent. He will run fast when I stop for about 10-12 seconds and then the engine tickover will slow suddenly, like a sticky cable just sprung back to 'off'. It never was the cable, the bike does it every time. If i wait for it to slow and then open the throttle to about 200 rpm for a few second, then let go, the fast-slow cycle repeats itself.



I have even wondered if there is something built into the ECU software to do this, hold the idle fast ready for you to move off, but after 10-12 seconds, then it slows the engine down.



OH, If I slowly open the throttle from tickover, quite often the engine just dies, but if I blip the throttle, then no problem???



An Enfield IS a unique ride!

Tornado, my old bullet only ever stalls on the very odd occasion that I do something wrong.

Thack, you may not like the fast tickover but it is set like that for a reason. I think, though I have no science behind this, it is better to keep the oil flowing round the thing. I can't see why else Eicher would have ste the tickover at that speed. As Jim and Michael have said the tick over is not perfectly reliable and my Continental GT does exactly what they say which is it slows down slightly from say 1150 to 1000 or 1050 rpm if you just shut the throttle and leave it shut at the lights. But should not you wait until it is run in before drawing any conclusions? They do take a while to bed down and mine was prone to occasional stalling when it was new, which is pretty well disappeared now.

Thanks for all those comments, guys.

Basically, this is terrible! There is no excuse, surely, for having an unreliable and unstable idle these days, especially when you've got an ECU with full control over the spark timing and mixture.

Interestingly, I don't think the ECU has any control over the actual throttle opening - I don't think there is any such actuator fitted, nor is there any mention of it in the official workshop manual. I think that must be why there is a fast-idle control on the left handlebar. Incidentally, the Bullet must surely be the only ECU-controlled, fuel-injected engine that has a manual fast idle control! I could hardly believe it when I saw it.

One day I want to wire up my Bullet to a full set of instrumentation and try to see just what it is that causes the idle speed to vary, to slow down, and to stop. Then maybe we could fix it.

EFI ignition runs on the same frequency as green traffic lights. notice how the engine will idle while the light is red but will stall as soon as the light changes to green. My Bullet will stall when 50 Hells Angles are behind me revving their Harleys, they must somehow suck the electricity away from my bike. Try telling this to young riders today and they wouldn`t believe you.

StephenR: yes, I they must have a reason for such a fast idle speed, especially when you think that virtually every motorcycle you can buy has an idle speed over 1000rpm. But most motorcycles have short stroke engines, which naturally rev higher. The EFi has the same bore/stroke as the old engines, which idled much more slowly, so I'm not convinced the any actual harm will come to the EFi. I'd love to know how the manufacturer decided on that idle speed. Oil films break down when the engine runs too slowly, as you suggest, but whether this is relevant here is anyone's guess.

Do we have any electronics guys amongst us? I want to get my hands on some kind of multi-channel data logger which will stream data to my PC for further analysis. There are professional solutions, but they can cost a fortune.

Mine (2010 EFI, 14500 miles) idles steady at 1000rpm. If it's a long wait at traffic lights, I give it just a little blip before take off just in case - it has stalled on me twice when taking off after a long wait with no blip. Bit embarrassing... But the idle is a lovely steady thump, no variation, a joy on the ear. I don't remember how it was after just 100 miles, but give it time, these engines get better and better over the first 1,000 miles - you'll really notice how it smooths out around 500 miles...

As i've said before my 2009 EFI Bullet de luxe with 9500 miles (not owned from new though)idles pretty well and if anything in my opinion is on the slow rather than the fast side but doesn't usually cut out.I'd rather have the idle a bit too fast than risk the engine stalling when turning right for example.I've had a 250 Superdream and GPZ900 stall on me in these circumstances which both times resulted in an embarrassing drop with a broken indicator and front brake lever.I also have a 2008 Kawasaki ER6 with EFI and i'd say out of the two the Enfield system amazingly seems to work better!