A Stumble

[valky1500]

I took the interstate out for a run last weekend. It's been sitting mostly since the tune up about 3 weeks ago where it got some new plugs.

After a 200 mile weekend and for something to do I took them out yesterday to look at them and see how things were going on inside.

They were brownish and looked good to me with the 5 and 6 plugs carboned some.

Then I remembered the shim trick that 2 brothers did back in the days when they were active. They found the back cylinders 5 and 6 running rich and that by removing the spacers from the needles of those 2 took care of that problem. So I did it.

Now there is a stumble at low rpm's when taking off and I can't pin point why other than removing those shims to lean them out. I plan to give it most of this week to see if it stays or not.

Where is the mistake in this reasoning?

[Ricky-D]

Trying to work out a course of action after making changes is fraught with peril, I say this because it sounds to me you have already made modifications to the carburetors.

If you are working from a stock configuration the thing to do would be to get back to stock and proceed from there.

Likewise with regard to your exhaust system. Being stock or not stock makes a difference.

So, I have to say the mistake is in not reporting all the modifications you have made to each system.

When you modify the carburetors (jets/needles) and the exhaust system you normally give up a bit of the drive-ability of your Valkyrie.

So what you experience is pretty much expected.

***

[sugerbear]

IF everything else is stock, i would have thought Honda would have thought of that,
and made allowance for it somewhere. could be wrong though.

[Blackduck]

Point 1, Honda designed these to accommodate the fun "police"
Point 2, Ignore Ricky, you may need to adjust the mixture screws on those 2 cylinders to richen them up a little for low speed response.
These units tend to run rich over 3000 rpm, Honda's design gurus did this.
If only slighty darker on the plugs I would not worry about it.
Put the shims back in and just enjoy he ride.
Cheers Steve