The needle in mine is the dynojet one, guess I should add that to my signature

 

Another shim it shall be.

Even with the baffle drilled, will stock exhaust offer any complications on top of this? As more fuel is added to the mix I don't want to run into back pressure issues...

 

AUS bikes come stock with a #132 main jet. Mine ran fine with the stock pipe. I can't foresee any problems as your main is still smaller than that (#125.)

 

Good to know. MY usa model came with 118 main jet. I kept going up till I got up to 132. It seems about right now.

David

 

From beginning of removal of side panels to putting the kickstand down after a short test ride in the neighborhood, the modification of my modification took 2.5 hr.

Didn't take it out on the highway but in the neighborhood tonight it seemed a little more peppy when I'd pop the throttle than before. Never exceeded 25mph, though. Tomorrow after work I will likely take it out for testing at much faster speeds. I'll report results afterwards.

Thanks to everyone for your posts, so far.

 

Just a bit of friendly advice, when talking about possible jetting/carb issues its better to state what throttle position the problem lies at instead of engine rpm.

Carb tuning is dictated by throttle opening (by knowing which fuel circuit is in use at the time) not rpm.

 

The original problem was less than 3/4 throttle.

For a while I've had a piece of tape on my right handlebar with 1/8 increments all the way from idle to full throttle so that I could tell what was happening and when. Sorry I neglected to mention that. Thanks for bringing it up.

 

Adding the extra shim to the stock needle to create .060" total lift fixed the problem. Now at further throttle opening it seems the surge may have moved to a higher point. At least its now out of my projected normal highway commuting speed range.

The new "maybe surge" is likely due to the main jet being a #125. Temp today during ride was 32*F and very low humidity meaning denser air. As temp and humidity will increase with the onset of warmer weather and yield richer A/F mixtures, I may wait a while to work with this issue. It may turn out to be a non issue. I have a #128 jet just in case, though...

Once again, thanks for everyone's replies.

 

What's the rpm and throttle position now when it surges?

 

Looks like around 7K at or just above 3/4 throttle...