F1 Sport Engine Cuts out

[barney]

Hi all,It's been a while since I posted and I'm pleased to say I had a couple of thousand trouble free miles. However the last couple of miles have been blighted with a problem.Symptoms,1 - The bike misfires and I often get a back fire. (Sometimes quite spectacular!)2- The tacho immediately dies as the bike miss fires.Today this got so bad that I coasted from 70mph to stand drill on the M40. The bike would not fire or pull and the tacho was completely dead.As soon as I stopped, I pressed the start, the bike fired up fine, with the tacho working as normal.Richard & all, am I right in thinking this is likely to be electrical? Reading the other posts it looks like the tacho is driven from the pulse to the coil. If I have no spark, does it thus mean I'll have no tacho?Is there a good place to start to look for this problem?Thanks in advance,Barney.

[Richard Negus]

Hi Barney,Forgive the brain fade, but do you have Boyer ignition, Startright digital or Norton digital ?You're correct in thinking the tacho is driven from a coil signal wire ; the yellow or black/yellow usually. On an F1, that would be the right/off-side coil.I've known Boyers fail on one plug, but failing on both sounds more like an intermittent power fault, the ballast resistor, or the trigger / trigger connections.R.

[barney]

Hi Richard,I have an NML unit on my bike. Sn 002 I seem to recall. I think the lights still work when the ignition fails. Is their a seperate fuse for the ignition? Or could this be a stand or kill switch problem?Thanks again Richard,Barney.

[Richard Negus]

Barney,PM me with your contact details and I'll organise another box for you.The first production box (#001) had a similar fault, corrected briefly by switching off and on again. Turned out to be faulty chip. Subsequent boxes have a different chip, I'm told.R.

[gripper]

My IP2 has a misfire until warmed up then runs fine apart from a really nasty habit of stopping dead for no good reason. Then for no good reason it will start again. Does the sparkright box fail in any particular fashion. Today it stopped just as I was pulling onto a busy roundabout. I've had some hairy moments over the years (crashed a Puma helicopter into the channel, been through a windscreen etc.) and that is up there with them.

[MrB]

Hope I never find myself on the same roller coaster as you then Gripper!

[Interpol2471]

Have you checked the ignition pick up, or my best guess would be the side stand switch as that will cut the ignition dead and then come back especially if you knock it without noticing.Disconnect it and see what happens as an easy check.

[gripper]

Don't do roller coasters, far too scary. Think I've eliminated the cutting out by re-routing the harness near the headlight, wires are a bit short round there. The mis-fire is still there for the first 3 miles then clears. I've got no retard box or sidestand cut-out. swapped coils, new HT leads and caps. ign trigger next on the list and then the sparkwrong box. I don't suppose Maplin do anything like ign triggers!!