pick up and grey transducer compatability

[pistonslap]

Noticed on my pickup says 'only to be used with grey transducers' - wondering whether this is really the case?
I want to start swapping either the pickup from another bike of mine to try with my grey transducers or the black transducers from another bike to try with this pickup.
My 1984 k1 bike has developed a problem that I think is electrical: Starts and seems to idle okay but as you accelerate one of the cylinders starts misfiring, popping and feeling pretty much like you are only running on one - - - power wise.
checked the spark and visually doesn't look bad when kicking it over.( which I guess figures if it is starting and idling okay) swapped the transducers around and checked all the connections and earthing points for them.
Hard for me to tell, on my own, which cylinder is popping etc. I guess I should try disconnecting the respective plugs and seeing how each cylinder runs on it's own
Any help much appreciated

[3potjohn]

I suppose you have checked the float bowls for water etc? I have no spare transducers or pickup but will be interested to see the outcome as I too have a K1.Isolating which cylinder or even both is the first stage.Holding the revs mid to high on the stand can you detect the pulses at the silencer end when it misfires or does it only do this when you are actually riding.I guess if its both you might think it is pickup based.

[robinh44]

Hi,

The grey transducers can only be used with the black pickup, the first generation was a red pickup that contained some diodes and a black transducer. In the grey transducer/black pickup arrangement the diodes were moved to the transducers. When you are isolating the cylinder as per previous checks suggested if you swap transducers round and the fault stays on same cylinder then it is more likely pickup or another factor on that cylinder ie carburation, if it moves with the transducer swap then the transducer is the likely culprit. Also check static timing mark on pickup, condition of spark plug leads and cap and when swapping also include spark plug as they can sometimes partially fail and give misfire problems.

Regards

Robin

[pistonslap]

Thanks for that Robin - I definitely won't be trying to 'mix and match' now.
Problem seemed to be with the front pot before swapping transducers (front pot and header decidedly cool)
After the swap and test ride I had to abandon testing (late at night and desperately needed a properly running bike for the morning) and concentrate my efforts on putting my Ducati instead.
I will next do what 3potjohn suggests and try and compare exhuast pulses while reving on centre stand.
a new plug for the front was my first port of call. HT leads, plug caps and connections were all checked while swapping transducers. I will drain carbs as 3potjohn also suggests because it is a quick thing to do but I'm pretty sure that the problem is not water as the last 3 or 4 journeys have been dry (amazingly) and the bike is garaged the rest of the time.
Static timing is also something I could check . I guess measuring resistance on the ignition coil on stator wouldn't do any harm . (presumably problems here would effect both pots?)
I will keep you posted on my findings and thanks alot for both you're help so far.
p.s sorry for refering to the cylinders as 'pots' all the time but it really is much quicker to type

[morini_tom]

Pistonslap-
check the pickup for signs of cracking. The resin potting often starts to crack. If this is the case on your pickup then it will be (or will soon be) causing the problems you describe.

George (who often advertises in the club magazine) can rebuild pickups for a very reasonable price, or NLM should be able to supply one.

[Daddy Dom]

How did you get on, Pistonslap? You have pretty much described my bike's trouble and after swapping them over, I also arrived at the transducer conclusion. Waiting on parts now.....
DD