Tuning pilot screws

I've already checked the float heights, they look good good. I quickly checked the exhaust temperatures and I think cylinder number 1 was a bit cooler than the others, but it's hard to tell - the all heated up. Cylinder number 1 was the sootier spark plug of the lot though so that makes sense. I was going to find my colourtune and see if I can get all the cylinders right at idle and go from there. Combined with the carb sync tool hopefully I should at lease be able to determine which cylinders are behaving.

I didn't say float heights. Fuel level as detailed in the factory service manual. Did you check that?

www.750turbo.com/manuals/GPz750_Base%20Manual.pdf

Sorry, I was using the two terms interchangeably. The fuel level was correct before I took the carbs off, so I didn't touch the float heights, I just measured the fuel level again after putting them back together, and all is good.

I did the clear tube test on the float bowls and the fuel in each carb fills to the height of the base of the float bowl bolts, which is what is stated in the manual. The bowls fill freely and don't leak if the tap is left on prime.

OK, a quick update on this one. I re-checked the fuel level in the carbs (I had taken the float bowl off to change the jets) and they're still good. I checked the coil resistances, which were good, and then changed the spark plugs.

It now runs pretty well and it's ridable. No misfire at any speed under throttle, but does pop on decelleration, and still has a slight hesitation on acceleration. So pretty sure it's still lean, but only a little.

Plugs after a short ride. It was only 10 minutes or so, but enough to get an idea. I rode home keeping the revs above 3000rpm and cut the engine before running into my driveway, so this should be an indication of the main jet I think:


My bike does have an aftermarket exhaust with a resonator (no baffles) - so I'm wondering if it's always been running lean all along. Perhaps it's worth going up a jet size? What jet size would be expected for a standard engine with no baffles. I'm still running the stock jet sizes.

Old post, but CruizinImage slow pilot jets are not real deal 35s. You have to drill them up as well as the emulsion holes. Just copy original slow idle jet sizes.