JohnBoy, you'd have to act like a rhino to do it harm. Take it easy and be gentle and no worries.

I think that I got the after fire issue fixed!
I went to my local carb shop and purchased a used spring from a Rochester 2BBL accelerator pump (see image)


The dimensions are the same but the wire diameter is different.
The original is .036 while the Rochester spring is only .025 making for less compressed tension.
The removal and replacement took much less time than driving to the carb shop.
I made several runs through the gears getting on and off the gas as hard as I could and I could not make it back-fire! I stopped several times, blipping the gas and shutting it off; but I could not induce the little burp we know so well.
The intake and exhaust on my bike are heavily modified, so I can't say that this spring will fix a stock bike...but I have a plan!! There are a couple of other riders here in Phoenix that I believe are riding stock machines. I will attempt to locate one of them and offer to “Fix”his bike for free ($2.00) and report back.
Once again...Thank you all for your help and support.
JB

I went in the carbs on the W today. The accelerator pump diaphragm is shot.. It Too is 57 bux,, but I dont get no stankin sprang with mine..

This was posted by Jespoker4fun on 3/15/10
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Ok, here is the link to order the spring for the air-cut valve.
http://www.carburetion.com/r2.asp
Just scroll down to part# 66-15
.95 plus shipping

Inside dia. = .385
length = 1.580
wire dia. = .025
I just checked the shipping charge from this site. They charge shipping &  handling.
Total for the spring will be about $12.00
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As can be seen on the photograph the number of coils and the overall dimensions appear to be the same. The outside diameter and inside diameter of both springs leave plenty of “wiggle room” for the post on the inside of the cover, and the cup on the diaphragm.

Johnboy was nice enough to send me one of the springs he found for the air cut diaphram so I popped it in to see what would happen.

There is definately a correlation to the backfiring going on here, if there is someone around Denver that has a stock bike and wants to see what happens I'm willing to help them try it.

P.S. my guess is this method would be similar to tuning your jetting except not as precise (seems to influence the whole range of circuits) and the spring tension would be different for various elevations and conditions.

FWIW, my feedback to JB is below...

thanks for info John,
BTW, got the spring yesterday. I think the 5 buck impact screwdriver I bought from Harbor freight a while back is the best investment I've made on this bike...

Anyway, here are my results...I installed it and it made the bike run horrible...no really!

I took your advice and upped the idle screw (same as you, I wasn't expecting that)...could barely keep it running even with the screw almost all the way in, turned the air mix screw in almost a full turn too.

Took it around the block and sure enough, there was absolutely NO backfires no matter how much I wound it out. I had pretty much eliminated the backfire on shutdown anyway so that was all good too.
Pulled into the garage and it smelled like a refinery + plenty of black smoke when you blipped the throttle...

I think with me being at a mile in elevation (richer) I was pretty dialed in with the jetting I'd set (#52.5 pilot w/bleed holes, 150 main and 2/3 spacer) and that when I replaced the spring it just made it too rich. I could probably go back to stock jetting and give it another go but I've already got it pretty much where I want it. I stuck the stock enrichment spring in and rode to work today and it was fine.
I'm thinking you may be right...someone with a stock bike could probably be successful with this as long as their elevation was near sea level...
It definately has a bearing on the backfire issue. I may take the spring you sent and see if I can find something kinda in-between what's stock and what you sent.
Thanks for all your help tho'...