The pop when shifting is the throttle closing ,I'd try opening the fuel mix screw from 1 1/4 to 1 1/2 0r 1 3/4 ''  and see if it stops.

batman wrote on 02/18/19 at 17:13:42:


And/or......don't let the throttle shut completely when shifting - just back off the throttle far enough for the rpm to drop (but not completely closed).

Slabslider:

When the bike idles fine at a steady speed - but stalls when you come to a stop (especially when you chop the throttle quickly)....is a sign of too low an idle speed or a lean mixture.

You should adjust your idle fuel mixture with the bike running.....not by just counting the number of turns from seated.  Opening the screw 1.5 turns gives you a good starting point - but the "setting" has to be done on a bike that is warmed up.  You need to adjust your idle speed pretty low for this adjustment - then turn the idle speed back up before you go riding.  If your idle speed is too high it is impossible to make the adjustment accurately, as the slide may be opening a small amount and allowing fuel to flow from the needle jet where the slide /needle is inserted.  Don't spend a lot of time with this....the oil pressure is low and there is no air flow over the engine - with experience this takes less than a minute to drop the idle speed, adjust the mixture, and then set the idle speed back up.

https://www.youtube.com/watch?v=YxpQjDQzX7g&t=269s

https://www.youtube.com/watch?v=zm5mB3R8Ucw&t=228s

If you can turn the idle fuel mixture all the way in and the bike doesn't go lean and stall - your #55 pilot jet is too big.

I think that a #55 pilot and #155 main is too big...even at sea level.  You should try running the next size jets and see if the performance doesn't improve - slightly rich mixtures can allow a bike to run OK....but the performance isn't crisp and you may notice more power with the next size smaller main jet.  Only having a single washer on the needle is also making the mixture rich....and 2 or 3 washers may improve the power.

The only time I have seen these large jets necessary is when somebody installs an open pipe and/or a cone filter that is not working well....and they are trying to compensate for the affects.  With a Dyna muffler and stock air filter, most often a #150 main, 3 washers and a #50 or #52.5 pilot jet work best (sometimes you need 2 washers if there is a surge at low throttle settings).  

SlabSlider wrote on 02/19/19 at 07:05:56:


Where exactly in GA are you?

Our rides depend on everyone's schedule, but maybe sometime in April/May/June and sometime later such as August...and if we get real brave maybe once more in October.  Just keep an eye on the Cafe and you will see us posting a topic for the rides a month or so on advance for planning with reasonably descriptive topic titles.

We will juggle our trips, sometimes going to the Dragon area in Robbinsville NC and other times staying further South around Suches GA. We usually camp and keep it inexpensive, but will occasionally get a cheap room or two if that's what everyone wants to do.

Usually me, Dave, MM, sometimes Oldfeller are the regulars.

I agree with everything David  said, but The one thing that stands out is only 1 washer on the needle jet ,I'd change that to 2 first, before swapping any jets.

Thought id report back on my experiments thus far.  Put another washer on the needle bringing me up to 2 total.  Adjusted the idle screw for max idle rpm.  Set at 2 1/4 turns. Bike will shut off if i turn the screw all the way in.  Ran it up in high gear like Dave recommended and did not notice any power surge or smoother running when i backed off at about 75 mph.  Mid range is smooth and bike seems to have plenty of acceleration.  Some small pops when closing the throttle while changing the lower gears but idles fine when stopping now.  No backfiring and no poof at shutdown.  I pulled the plug and it was a nice desert tan color. I think ill stay with the 55 pilot and 155 main for now and just see how she does.  Im pleased with the performance overall. Thanks for all the tips, much appreciated!