One dead cylinder

[pistolchamp]

I do most of the work on my bikes and this one has me stumped.

At very low rpm (800 or so) when I give the bike very small throttle openings she misses on just one cylinder (yes I can tell) and if just the smallest bit more gas is given the miss disappears and she runs like a champ.  Together we have over 93,000 miles with zero trips to the dealership (other than tire changes) and I sill love her.

Recentley I've seen a couple of threads about a low speed jet that is adjustable, could this be part or all of the problem?  If so, where are they located and how easily are they adjusted?

In all these miles (many two up with a heavy trailer) there have been no real issues.  She has all the power she started with, gets better gas milage than when new and is still great fun to ride, darkside and all.

I wish all my mechanical stuff was this reliable.

Kent

[Ricky-D]

Sounds like a synchronization related problem.

When this seems the cause of a problem I always recommend first to lubricate all the linkage under the chrome covers down by the carburetors. A couple screws and the covers slip right off.

Plenty of generously applied spray is the suggestion, don't worry about a mess, it will all drip off and run down out of the way. Work the throttle vigorously while doing the spraying.

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[gordonv]

If this is a low speed stumble, couldn't it also be a clogged slow jet?

If so, add some carb cleaner and run the engine at low rpm to have it go through (top gear, slow MPH).

Cleaner would be the one of your choice, Seafoam, Techron, B-12, 1/2 tank of gas and 1/2-full can of cleaner to it. I've moved over to running my bikes with Chevron gas, just to get the Techron in my fuel.

[Ricky-D]

It sure could!

The idle noted was 800rpm which is too low anyway.

All the problem may go away and stay away if you raise the idle to 900rpm and even a little higher to 1000rpm.

Just a thought.

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[John U.]

Recentley I've seen a couple of threads about a low speed jet that is adjustable, could this be part or all of the problem?  If so, where are they located and how easily are they adjusted?


Kent

The adjustable parts are the pilot screws on each carb. If you change that adjustment you will need to do a carb synchronization so they are all pulling the same. Try the Techron first. Ethanol in the fuel can clog slow jets pretty fast; due to the fact that Valks have 6 carbs the slow jet orfice is pretty small. It's a very common problem. I just can't wait for E-15.