Jetting SP III

[dxhall]

This bike has PHF 36 Dellortos now with K27 needle in the middle groove, 130 main jet, and 48 idle jet.  It came from Alabama, so probably close to sea level.  The plugs show it was too rich there.  Here in Denver it will be worse.  Any suggestion on what I should change?  If someone has a good setup, I could avoid a lot of trial and error tuning.

[yogidozer]

I would drop the needle a notch, and see what that does for you. Try new plugs, or clean the ones you have now really well.

[pete roper]

Before you do anything else pop the top off a carb and lift the slide out and see if they have a shroud around the atmospheric side of the atomiser orifice. This makes a huge difference to the required jetting.

[dxhall]

There’s a shroud 360d around the atomizer.  It sticks up about 3mm into the carb throat.

[guzzisteve]

Some good stuff right here--- For your area stock pipes, stock set up

http://www.thisoldtractor.com/dellorto.html

On the PHF's alot has to do w/throttle hand, the more you twist the more it squirts
Mine was set up to go, had the headpipes off my LM3 on it, x-over, Lafraconi open exhausts. Mallosi air filters

Pete's going to tell you bout lean burn PHF's

I would make sure it has the smaller stock atomizer in it not 268's but 262's and AB's not AR's
If you keep the K27 needle, 264 atomizer would be almost correct. I always lived close to sea level, though. The size of the pump jet will make it look rich also.