Misfire Troubleshooting

Still waiting for the CNW hub and TheChainMan duplex to arrive. Both were sent by postal services as I couldn't stomach the extortionate rates for courier plus brokerage into Canada.

Bike is in pieces and weather is nice :-(

Maybe spend some time getting put back as far as possible so when missing parts show , in they go and off you go !

I have had exactly the same problem as Tornado, re LH misfire, smoke etc. went thru the same eliminating process, coils leads, carbs ad infinitum. Bit the bullet and took head off the motor. PO had fitted a copper ring composite gasket and both pushrod tunnel openings were very badly alligned to where the actual tunnels were when fitted. Polishing marks on both exhaust push-rods, and a very soggy gasket between push-rod holes and bores and evidence of bad/incomplete sealing.
Tornado's symptoms are uncannily similar so that's my 2 bobs worth

johnny Lagdon said:

I have had exactly the same problem as Tornado, re LH misfire, smoke etc. went thru the same eliminating process, coils leads, carbs ad infinitum. Bit the bullet and took head off the motor. PO had fitted a copper ring composite gasket and both pushrod tunnel openings were very badly alligned to where the actual tunnels were when fitted. Polishing marks on both exhaust push-rods, and a very soggy gasket between push-rod holes and bores and evidence of bad/incomplete sealing.
Tornado's symptoms are uncannily similar so that's my 2 bobs worth

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Note my most recent results after fitting the single carb and clearing the inlet rocker oil drain passage, fresh plugs....bike was running very well, no more smoke and no misfiring. Next test is to put dual carbs back. If that's good then conclusion is the oil drain lead to excess oil in left side cylinder, giving misfires.

But that test requires receiving the remaining part I've had on order now for 6 weeks (clutch hub). My test ride had an unrelated issue when the inner primary cover bolts came loose, damaged chain. Hub was fairly worn so prudent to put in a fresh one...the CNW hardened version was actually cheaper then the AN one, esp before shipping.

So the old adage “time is money” could relate 6 wks is wayyyy long , in hind sight maybe the extra coin would have been well spent , hope for you it on doorstep Monday morning !

Well well well,


that took a wee while!

Answers soon , right .... been a long wait for all .... glad it finally arrived and you not long for the open road !

Slowly reassembling after carefully cleaning. New clutch center went in the new bearing without any drive force. Is that a concern? Book and CNW instructions imply a press fit is needed.
Got to slacken off gearbox to cradle adjusters next as can't place sprockets with new duplex chain on as is.

All the centres I have replaced bearings have needed a vice on the bearing, does not sound right. That said as its steel on steel Loctite will keep it in place but the clutch bearing has a tight inner clearance that expects an interference fit to close this up a touch to reduce clutch wobble.

kommando said:

All the centres I have replaced bearings have needed a vice on the bearing, does not sound right. That said as its steel on steel Loctite will keep it in place but the clutch bearing has a tight inner clearance that expects an interference fit to close this up a touch to reduce clutch wobble.

Click to expand...

There is definitely wobble play in the basket from the bearing, but not the center to bearing race, which though not tight, has no discernable movement when seated. Maybe AN sent me a duff bearing? Original seems serviceable. Didnt want to return it to the bike.
Ive got clutch and chain on bile now. Used red locktite on the offending three inner case bolts, plus new tab washers, torqued to spec at 80 in-lbs. I checked sprocket alignment, clutch is maybe 0.1mm closer to case edge than crank side. Is that enough to warrant more shims (havent got any extra)?
I placed the duplex chain on the outer side sprockets as chain is heavy duty, a bit thicker than stock and when test fit on inner sprockets I didnt like how close it was to casing surface, contact easily made with a little chain side slap.