CB550K3 with PD carbs

[Johnny4428]

Without boring everybody with the PD woes, I fired up the 550 today after about 6 months in winter storage and I have never had this bike so keen to start in the 35 years I have had it. Especially coming out of winter storage. I had to remove the carbs after I discovered the tank filter had a hole in it. So decided to order as I should have done earlier new pilots, instead of ordering 42’s I ordered 45’s. Also I refurbished the coils with new leads (as per the Ash blurb). But I will reserve further bragging rights in anticipation of a proper road test. Happy days! 😄

(had to close choke to keep running too after about 20 seconds running)

[Bryanj]

Sounds like a good idea, they were designed to be "lean burn" for the US market so probably a good mod.
Where did you get the pilots from?

[Johnny4428]

Sirius Consolidated Bryan. Just wondering now if I have to adjust the mixture screw any from standard setting.

[Bryanj]

Possibly but they have a very fine adjustment as the pin is tiny DO NOT screw them in very tight or you will damage the pin and seat.
I take it you know there is a spring, tiny washer and O ring on each screw

[deltarider]

Here is how it looks.

[Johnny4428]

Yes had them stripped completely for initial clean and refurbishment of carbs. Thanks for the pics all the same. I’ll have a play about. Had a quick 12 mile blast this afternoon and running great, just hanging on that idle a bit. But great starting.

[K2-K6]

The PD carbs on 750 F2 always responded well to a squirt of their accelerator pump to start them from even slightly cooled down, just a little extra to get them a little richer and aid instant starting.

I know that not many like the PD carbs  but they do meter particularly accurate fueling, almost to injection levels of detail, thats along with quite clean burning combustion.  Always good for exhaust life if unburnt fuel is not slooshed through the motor, oil condition too also benefits from this, and it follows that bearings etc do benefit from this.

They maybe finicky, but they are effective.

[deltarider]

How about increased heat and the valves?

[K2-K6]

How about increased heat and the valves?

Increased heat from which source?

[deltarider]

A leaner burning, what else?