Z1OwnersClub GB

My ELR started to misfire at Donnington and I have replaced the plugs and checked for loose connections. I went out for a ride today and within a mile it started to play up again. The rev counter flicks all over the place and does not match the revs of the bike, then the engine starts to run rough and occcasionally cuts out. It starts okay on the stand and seems to run fine.
The bike has four Dyna coils fitted and also Dyna S ignition.
Any poinetrs would be helpful before I start stripping it down.
Cheers Rob

Rob the fact that the rev counter needle is very erratic suggests its electrical
have You checked all conections going to the coils

If is an electronic rev counter it may pick up from the coils have you a circuit diagram.if it happens when bike is warm it may be a coil breaking down,hard to tell if its the Dyna,without substitution,,,check your battery and make sure you a good 12volts at the coils,is the bike charging well? you should be getting a good 14.5volts across battery at 3k revs,also check all earths are good!

+1 ON THE COILS

You say it starts well on the stand. If so is that the side stand & does it still have the safety cut out switch connected? If it does check that wiring & that at the switch by the clutch lever.

I had similar when alternator wires went bad/broken strands of wire. Was not getting charge and rev counter was going high and low and then misfire when battery discharged
Get the multimeter out and check the 3 wires coming from alternator, should get equal readings across any combination of two wires, mine were around 0.9.
See how many volts at battery with engine off and then running, needs to be over 13 volts, around 13.2 is good IIRC.
Checking rectifier is harder, but luckily for me found fault straight away and fitted used genny.

I take it you have the correct leads and lead ends fitted (i.e. not plug caps).
If you have NGK plug caps fitted, the Dyna coils fry the resistors inside causing massive misfires etc.

I have spotted a broken wire on the front left hand coil, so hopefully it will be fixed shortly

Rob

Robw wrote:I have spotted a broken wire on the front left hand coil, so hopefully it will be fixed shortly

Rob

Good Luck Rob we like cheap fixes

good result Rob

Robw wrote:My ELR started to misfire at Donnington and I have replaced the plugs and checked for loose connections. I went out for a ride today and within a mile it started to play up again. The rev counter flicks all over the place and does not match the revs of the bike, then the engine starts to run rough and occcasionally cuts out. It starts okay on the stand and seems to run fine.
The bike has four Dyna coils fitted and also Dyna S ignition.
Any poinetrs would be helpful before I start stripping it down.
Cheers Rob

On my H&@da VFR 750 this fault was a typical symptom of a rectifier failing

Although the bike now runs better at idle and low revs when I took it onto the dual carriage way it started to misfire at about 70 mph. I rode it back through town and it seemed okay.
I have bought new leads and have checked the rev counter which looks fine.
I intend to look at the wires to see if I can see any damage.Any other ideas?
Cheers Rob

Just did the tests for the alternator and battery
Battery volt at rest 11.9
12.73 v @ 1500rpm
14.43 v @ 3000 rpm

Checking alt output voltage
All yellow leads approx 38 v
also the rev counter jumps at 4000rpm on this test.

Yellow leads resistance is 0.7 ohms should be no more than 0.5 ohms.
I have fitted a new stator before the test, so couldit be the rotor

.

Test seem ok but a lead acid battery should produce 2.2 volts per cell 6 times 2,2 =13.2 volts off load.i it a peramanent magnet type rotor? are you sure your coils are good?,put a meter on your rev counter and see if the voltage jumps or is stable....Paul J

Paul, it is a permanent magnet rotor. I will check the coils
Rob