Honda-SOHC

Thanks for the reply’s and sorry for the delay in replying. The bike is a CB550K2 with the non PD type carbs.

Why do you say the colourtune does not work for our bikes deltarider?

I’ve just spent a small fortune at cms for a few sizes of main and pilot jets to do some experimentation.

I’m supposed to be going on a road trip to Germany at the end of July. It’s looking unlikely at the moment!

I’m having issues with the running of my CB550 and could do with some advice.

Carbs refurbished by Gerben - new main and pilot jets and fuel cut off valves (stock sizes 38 pilot 100 main)

Boyer Bransden ignition with micro coils - new 5k plug caps

Several sets of ngk d7ea plugs

Delkevic 4-1 exhaust.

Stock air box with new filter, inlet carb rubbers and o rings.

Ignition set, carbs synced. Bike starts and idles fine.

From idle to about 1/4 it runs really rich and stutters and bogs. Runs fine from 1/4 to wide open throttle.
I’ve used a colour tune which confirms it’s running really rich in the problem area.
It keeps sooting up plugs because of this.

So far I’ve set the air screws at 2 turns out, (1/2 turn leaner) which helps a bit.

I’ve checked the float levels with a gauge and clear tube method. They were almost level with the float bowl so have lowered them by a few mm which hasn’t made any difference.

I’ve have tried running with the needles 1 position lower which helps quite a bit with the low end running but then runs lean from half throttle onwards.
Have considered keeping the needles in this position and jetting up the mains to help the lean top end running.

I’m at a bit of a loss as I’d of thought it should run fine on stock settings even with the delkevic exhaust.

Any advice would be greatly appreciated. Thanks. Luke.

I’ve sent a PM, I’m still interested in one.

I've only got as far as stripping them so far. I'll take the stanchions to work tomorrow and check them for straightness.
From what I've read if I send them to Philpotts they'll straighten them before chroming them if required.
In my opinion the lowers are scrap. I'm guessing I could dress out the damage and they might be ok, but I'd be gutted if I had the uppers rechromed and they wore out prematurely due to the wear on the lowers.
I've had a look about for some replacements. there's a few sets on ebay from the likes of DK but looking at the condition of them there's no guarantee that they be in any better condition than what i've got already.
Being 341 lowers I could look for CB750 K2-K6 forks also? Am I right? I know the uppers would be no good as they'd be too long.

Thank you for your informed replies.

Yes I would of thought it would of had a yellow plate, but the type of yellow plate I was more unsure of. I'm less keen on a modern reflective plate as it doesn't seem right that a 40 year old bike would have the same type of plate as a brand new bike. I'm swaying towards the type with the raised digits riveted on.

So you wouldn't bother going to the trouble of running the bike on fuel with the ethanol removed by the likes of one of those ethanil kits? I did look into them but it seems a bit of a faff.
Would running the bike on good quality non supermarket fuel then draining the bowls be enough then?

I take it you mean the aftermarket kits dss sell Julie? It was the genuine Honda kits I priced up that cost the money.
Thanks for the eBay link MeilakJ, that's exactly the sort of thing I'm after.
I'll go with that kit first and if it turns out I need any of the other bits I'll bear the cruzin image kit in mind.
Thanks for the replies guys. Luke