This is so the guys will have an idea to where to start their jetting. Please post motor mods, and altitude. 
1975 S3a
26,xxx miles
2nd overbore, factory pistons
Stock porting and carbs
Stock slides, 2nd set of stock needles, set at 2nd from top notch.
Stock pilots, 1.3/4 turns out, give or take...
Main jets from 100 to 105, currently running 105s
Stock points, plugs, wires, timing set to factory pointers.
Denco street chambers, baffles fully packed.
Stock oil pump backed off to closed throttle stop, cam pointer is 1/4 inch from full-throttle pointer at full throttle, but no slack in cable.
Castrol GP s-stroke oil.
Premium fuel
I'm in Southern California, at sea level...
I use one of those old carb tools with the floating ball to set idle adjustment, if you spin the center disk all the way in, it will actually work!
For full throttle slide adjustment, I use my fingers to see if the slides are equal at the top of the carb bore at WOT, adjust cables as needed.
I special ordered a set of big K@N oval air filters to match the stock carbs, but midrange suffered, as it does with no filters. The solution was to use the stock air boots (between the carbs and stock airbox) and cut them down to about 1.75-2.0 inches, and mount the airfilters to those with pop rivets. This really helped the 4000-6000 range.
Around town, the bike is a pussycat, it pulls smoothly from 3500 without loading up, no blubbering at part throttle,but really comes on around 5500, with the peak arriving at about 7400. It pulls hard to about 8500, not much else above that, excellent torque, with a big push at every upshift, the nose actually rises with every new gear! The Dencos really made a big difference! It pulls in 3rd like it used to pull in 2nd with the stock pipes!
Part throttle is very sensitive to needle height, one notch up or down makes a big difference.
I think the chambers made a big torque difference, rather that HP. I can lift the front in first regularly, just twist!
Hope this helps someone.
CB
UPDATE!! 6/26/08
I have now set the mains at #100, put the needles in the leanest position, and set the timing a touch retarded...Im using points and a test light, setting timing at about 2mm past the pointer in the window (scientific, EH?)
The pilot adjust screws are now in the 2-2.5 turn range, runs excellent at
sea level, about 80f outside...I used H2Runners tuning tips on the carbs.
I think it's the bikes' best best tune yet! I wouldn't change a thing!!
CB
Update 7/7/08
I now use a 3-wire Tach-Dwell to set my points (29 degrees on 6-cyl scale) and a timing light to set to stock pointers, really runs better, more even running, better throttle response!
CB
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