Hesitation, stuttering, misfire - help please (2020)

I’m sorry to add to the confusion I’ve caused, however, today I’m feeling a lot better. I went out for a nice ride again, it’s is running very nicely despite having the incorrect 4 ring needles in the flat, tall spray tube. I have been through the specs. for all 3 models of 850 in the Andover Norton files, and each of them backs up the info given to me above i.e. To use 4 rings in a stepped spray tube. For now it’s working and so I’ll leave it alone until it figures out that it’s supposed to mess around.

it’s a bit like how a honey bee isn’t supposed to be able to fly, but no-one told the bee . Reminds me, I’ve got a nice jar of honey in the cupboard I picked up in the Dolomites last summer.

i would try NEW 106 needle jets and go back to the 2 ring needles.

bill said:

i would try NEW 106 needle jets and go back to the 2 ring needles.

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They are all new components already. I may go back to the 2 ring needles if I get bored after the next ride and see what happens.

Well today another longer ride and it rode faultlessly. 40 miles to a nearby dealership which had quite a large number of clients outside in the sunshine - I clicked out of gear, flicked out the sidestand (phew, I’ve now mastered that) and it ticked over beautifully. Thankfully it showed just how good old school bikes really were. I had a few people look it over. Then I had a long chat with the owner of the dealership, as he had been the one who put me onto it, and discussed something other possible projects for me to consider. Finally it was time to depart, helmet on etc. ignition on, fuel on, and in front of everybody it started second prod. I was well impressed, I hope they were too. Then another 40+ miles home again and all was well.

Not one, but BOTH SIDES had backed out. Bike was still ridable, no black smoke, but an intermittent hesitation & misfire, sometimes good idle, sometimes not. Fuel economy was about 30-40% worse.
Premiers with 10K miles on them, I did not confirm assembly before bolting them on. Should have. Take them apart & recheck before putting in service.

concours said:

Not one, but BOTH SIDES had backed out. Bike was still ridable, no black smoke, but an intermittent hesitation & misfire, sometimes good idle, sometimes not. Fuel economy was about 30-40% worse.
Premiers with 10K miles on them, I did not confirm assembly before bolting them on. Should have. Take them apart & recheck before putting in service. View attachment 95429View attachment 95430

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Looks serious ....... Reckon it needs a full length run of the Kancamagus to verify your repair

concours said:

Not one, but BOTH SIDES had backed out. Bike was still ridable, no black smoke, but an intermittent hesitation & misfire, sometimes good idle, sometimes not. Fuel economy was about 30-40% worse.
Premiers with 10K miles on them, I did not confirm assembly before bolting them on. Should have. Take them apart & recheck before putting in service.

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Where did you buy your Premiers from?

I know that some NA suppliers bring in "generic" carbs, then jet them accordingly to suit the customers needs at time of sale. I have always been kind of concerned if the main jets were swapped through the float bowl drain plug hole, and how this would affect the jet holder torque....

Derek Wilson said:

Where did you buy your Premiers from?

I know that some NA suppliers bring in "generic" carbs, then jet them accordingly to suit the customers needs at time of sale. I have always been kind of concerned if the main jets were swapped through the float bowl drain plug hole, and how this would affect the jet holder torque....

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Dude Wheeler at Gate City Cycle, Nashua NH. Pretty sure they were Commando specific.

Perhaps locktite could be used sparingly on main jet threads?

The jet holder thread is BIG… the main jet thread is small.

The jet holder can be tightened sufficiently so as to allow jet removal and replacement without Loctite.

But I guess a wee drop wouldn’t hurt anything if that gave you peace of mind.