Intermittent cutting out

[nellyboyo]

AAAArggh ,, after 3 days of breaking down ( 25 times plus !! ) and fault finding I`m l left with the stator which reads fine and has a new LT coil fitted as part of the saga OR the flywheel . I have changed everything else and I cant believe it would be that.
Its an AF lightened flywheel and then breakdown only occurs after a few miles and when the bike is really warm .
When it dies there's no spark ... take a few readings and then it`ll run again for 500 yards before dieing again.
I`m now 2 stone lighter and have even less hair that 3 days ago.

[storkfoot]

Trying another flywheel, or replacing the pick up would be reasonable places to start. Breaking down when the engine has warmed up is often a sign of pick up problems but, in my experience, these flywheels can also be problematic.

[coaster]

Get yourself a magnifying glass and have a really good look at all the soldered connections on the stator and check that the little earth terminals are secure. LT coils can be quite fragile as the wire is as thin as hair and can easily break due to vibration. I have found 2 faulty LT coils by connecting a meter on ohms between earth and the green wire and gently taping the body of the coil with a non conductive tool (thin piece of wood). You coul;d try a different CDI but they generally faiol completely.

[nellyboyo]

Cheers boys .. I am 3 feet past the end of my tether now , there is only the pick up or flywheel really left , hard to believe a fixed item like a flywheel could expand and then fail. I have re-soldered all the joints on the stator , I pulled the kill green wire so the problem is before the cdi , cheers

[storkfoot]

Is there any indication that the pickup has been fouling on the flywheel? Has the stator and flywheel combination worked well before, or have you just put it together? Is the flywheel one of the newer type with the spacer on the boss under the rivets?

[nellyboyo]

Its done about 1000 miles since the build and despite, other niggles I haven't had to touch the ignition. This is the first AF flywheel I've had and it was built in September so I would say its the newest they do ?? I haven`t seen any others .
There wasn`t any indication of rubbing that I noticed when I took it off . The tape on the lighting coils was falling off and there was a small piece of square foil which my mate reckoned had come off the LT coil ( which was reading low (320 ohms) ) , So I pulled the tape off and fitted a new LT coil ( 390 ohms ) ............and then carried on breaking down as before .

[goldeneye]

sounds like the pick up to me. done a lads P2 with the same problem, he would break down in practically the same spot everyday, and would get another couple of miles after letting the motor cool down and re-started, for the same to happen again. changed the pick up and it was fine.

[coaster]

...... So I pulled the tape off and fitted a new LT coil ( 390 ohms ) ............and then carried on breaking down as before .

390 ohms is well bellow what I would concider using, 450 ish is normal and the BGM coils are even higher. Goldeneye could also be right about the pickup, what reading do yoy get off that? look for 95 - 110 ohms, higher the better. But, as I mentioned before, if the fault is due to a break in the coil wire it will not necessarily show up with the engine not running as it will be affected by vibration. Therefore, tap the coils whilst watching the meter to see if there is any change in the resistance. You must use a non-magnetic tool for this though or you will see false readings.

[nellyboyo]

Cheers all , flywheel will be off tomorrow and I'll do the pick up some more fault finding.......too hungover today after the rugby

[coaster]

.......too hungover today after the rugby

Ah, just realised the Welsh username, I'm half welsh myself (dad) and found myslef in a pub in Dundee last Saturday visiting friends. I was the only welsh supporter in the entire bar, all good humoured though....and I have very little recollection of the rest of the evening