Engine misfire / Knock

[wolffie]

Hi I have a 1985 MHR 900 (Square Case) and I have off and on had issues with the front cylinder not firing so I would change the plug and all is good again.

Intill recently i had left to go on a ride when around the corner from home i notices a ticking from the engine, this tick quick became a knock and the front cylinder stopped firing running now on only 1 cylinder but with now on knocking. I got my bike home thinking it may be the plug issue again so i put in a new plug in and fired it up. It fired up on 2 cylinders but with the knocking and after running for a few seconds the front cylinder stops firing again but with no knocking.

I have been told maybe big end to a crack in the resin that surounds the electronic module which oil gets into shorting the out the ignition creating a radical spark.

Has any one experienced the same issue ?

[darren nix]

I was having the same problem so after doing up my heads on my 81 mhr [ that was the path i was chasing down] i still couldn't do more than 40 km before droping down to one cylinder, so i put in a set of dyna coils that steve sells and haven't looked back since, even if your coils aren't shot it's a great investment, turned my mhr into a first kick start all the time now, dyna coils have been in nearly 4 years now and still going strong

[toomuch]

How about when the engine is warm ? Having a hard time when warm Cold engine no problem

[wolffie]

warm or cold makes no difference.

[Grover]

Have you checked to see what the spark is like in that cyl WHILE its running?.....the centre steel insert on the ign pickups tend to move out and hit the rotor, have you checked these, under your clutch cover. Ron Young pinned mine a few years back when I detonated a gearbox, they had got real close to the rotor