drops a cylinder

[tony.mon]

Yes, it's wasted spark, but the unused spark is on the same cylinder, not the other one.
So the rear cylinder coil fires every time the piston reaches the F mark before TDC.
Note that the wasted spark position on the rear cyl will not be at the correct sparking position for the front cyl, and vice versa.

It's likely that the ECU would output a spark trigger signal to both or neither, so the damage is likely to be to the coil rather than the ECU, and that's easy to check- a coil from any 12v bike will give a spark.

[griffo117]

It's a red she by the way.

All the best ones are (did I mention speed? )

are we getting into the colour debate again?????? we all know yellow is supreme

[sirch345]

Hi Chris, what Tony has said is more or less what I would have, cheers Tony See what the bike is like with the new stick coils and possible new plugs, or swap over from front cylinder to rear at least. Good luck with it,

Chris.

[bucklandswifty]

Thanks for the replies Chris & Tony. I am hoping to finish the Stick Coil mods tonight and test. I have a sneaking suspicion that rings or valves have been damaged. When the bike is running the misfire sounds almost as if there were another detonation going on, hard to describe really. Is the wasted spark on the exhaust stroke then? What sort of damage might I have done when the cct’s were too tight? It did take a bit of starting when it was hot, but sounded okay when running, none of the misfire then. Not sure if I mentioned, I did clean the ECU & ICU contacts with proper spray contact cleaner, I guess this should be okay though, the units are resin potted.

Cheers - Chris

[tony.mon]

If CCT's are too tight, the cam is pulled down into the lower half of the camshaft bearing surface, especially on the chain side.
This may well have been so tight that oil could not flow into the gap and keep the metal parts (cam and head journal) form touching.
If that's happened for more than a few seconds then the likelihood is that the head has worn, due to bits of molten alloy being picked up anad weleded to the camshaft bearing surface and acting as a file into the journal surface.

The only way to know is to strip and inspect.
If this has happened then you need replacement heads, possibly and cams as well.

Unlikely to be rings, as they are usually very reliable.

But could be damaged valves, if you had a cct fail.
If so, pull the head and have a look.

[bucklandswifty]

Thanks again Tony. I will have Front Row Motorcycles check it out. I am sure the cct's did not fail, the oil starvation is a real possibility though. What cannot be stressed too much is how easy it is to over tighten the manual cct's by hand, just moderate finger and thumb turning gets them way too tight even before you feel any serious resistance!

[Wicky]

Hence why finger tight then back out by a 1/4 – ½ turn

Thanks again Tony. I will have Front Row Motorcycles check it out. I am sure the cct's did not fail, the oil starvation is a real possibility though. What cannot be stressed too much is how easy it is to over tighten the manual cct's by hand, just moderate finger and thumb turning gets them way too tight even before you feel any serious resistance!

[Diabolus]

im reseting tension via the backing out whilst idling method to be certain tension is correct for both pots as per http://www.haymouth.co.uk/phpBB3/viewto ... =9&t=22693.
I have a 500mile + charity ride in june and want to be confident there set right.

[bucklandswifty]

I hear what you’re saying Wicky re backing out 1\4 to 1\2 turn - I found that with the cam cover off and winding the tensioner in by finger and thumb until a moderate amount of resistance was felt then backing out 1\2 a turn it was still not giving the 5mm to 8mm deflection at the midpoint between sprockets. I was well surprised at just how "loose" the cct was when correctly adjusted. Not forgetting the locktite, without it I am sure they would move.

Chris

[bucklandswifty]

Finally found the misfire was due to either the ICU or the amplifier unit. I got replacements from Ebay, fitted them and the misfire was gone. Frontrow Motorcycles checked the bike over and found it was in very good condition, compression tests 165 front and 160 rear. Cam chain tension was spot on and no damage from my previously way over tight settings. I think my ICU\amplifier problems were caused by overzealous cleaning and blowing water up the number plate, where there is a not so handy gap straight through to the electronics.