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CB550K3 carb needles ???

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OZZYSBIKES:
HI,

I have a CB550K3 and it has never run well since the first day of ownership, it has always run very poor at low throttle openings so I have removed the bank of carbs to overhaul them,

On strip down I have found that the needles fitted in the carbs are 4mm shorter than the new ones provided in the service kits, this could explain the poor running at low throttle openings (some of the stuff that I have found engineering wise on the bike means anything is possible), I have also found blocked airways that could explain the poor running,

The carbs are the Keihin PD46A suffix PJ t

does anyone know which are the correct needles as it is not 100% certain by looking and measuring which ones it should be,

Any info / help much appreciated.

Nurse Julie:
PD's are notoriously shite and always have been that's why most people bin them given an opportunity. No idea about needle length though but if your carbs have never been apart, or at least, had brass ware changed, I would suggest you have not got the correct replacement parts.

SteveD CB500K0:
I think the general consensus on here is to save your time and money and get a set of carbs from an “F”.

Then spend your time and money setting them up.

I’ve had three K3s. None in the last 20 years though.
They were great in the 70s but I suspect they don’t like modern fuel very much.

Steve

Another vote on pictures please. You need five posts to attach pics, but I’m sure that won’t be an issue for long


Sent from my iPhone using Tapatalk

OZZYSBIKES:
Thanks for that,

I agree with the fact that the PD carbs are shite but CR carbs are a tad pricey ! I am making the best of what is on it, do people put the earlier carbs on as a replacement ?

I have no idea what the previous owner has or hasn't done with the bike or any of the other owners so cannot be sure on whether the needles have ever been replaced, I guess no one has compared the PD needles with any others I.E. the ones from the previous type of carbs ?

If no real answer to the needle length relative to the type of carbs fitted I will measure carefully and use my judgement, it is looking like the short ones are correct for the PD carbs.

OZZYSBIKES:
HI Steve,

Yes I agree about getting another set of carbs, I intend converting it to look like a F2 and fit a 650 cam plus possibly a big bore kit as I love the relaxed ride that you get with the bike (my son calls it the armchair) but it could do to be a bit more capable of motorway speed cruising, I already have a good four into one exhaust so the better carbs will fit in with my plans for this bike,

Cheers

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