Blackbird feeling poorly!

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Fired up the Blackbird at the weekend after she has been stood for nearly 2 years.
Fitted a new battery and pressed the button with full choke and after a couple of attempts she started.
Now something didn't sound right, seems to be a bit lumpy and just dies if I twist the throttle of take the choke off.
Its a 1998 carb version so maybe needs a clean?

Any sensible advice or suggestions would be appreciated.
 
Fuel bowls and jets will be bogging!
At the very least it’ll need flushing with cleaner and fresh fuel but I’d be taking the bank off tbh
 
In addition to the above I'd be changing the oil and filter Then turn the motor over for a while to circulate the new oil without letting it fire up :beerjug:
 
Give those carbs a nice relaxing ultrasonic bath. They've done 21 years without a clean probably.
 
UPDATE

Finally got round to cleaning the carbs. Took the bank off, took off the float bowls and cleaned the jets. Replaced the spark plugs as well.
Put it all back together and no change......

Whats next??
 
IF you’re sure you’re getting a good spark, go back to the carbs. First check fuel is getting to and filling the float bowls, if not, check the fuel tank and filters for blockages.

Sometimes carb cleaner alone will not be enough to clear fuel varnish or dirt blockages from all the nooks and crannies inside the carbs where you can’t get proper access to. A good session (or two) in an ultrasonic cleaner can work wonders.
 
When people say they've cleaned the jets, they usually haven't quite done so fully.
Did you remove all of the jets from their seats and fully clean through and visually check the orifices?
Did you remove the emulsion tubes and check/clean the through holes as well as the tiny sideways orifices?
Did you blow through all the air passageways and blast carb cleaner through them?

There's usually no need for an ultrasonic bath, and many people just chuck carbs in thinking they'll come out fully sorted and ready to use.
Almost snake oil, an expensive waste of time.

Do it thoroughly and check visually as far as possible.
There'll still be some shite somewhere.
 
Good advice you’ve given there Tarka. But your opinion on ultrasonic cleaners seems prejudiced. At my company they were used on an almost daily basis and were particularly useful on stubborn carbs when all else had failed.
 
Surely you can't just put a carb in an expect it to be cleaned, it'll need stripping to its component parts and then checked carefully on reassembly.
 
You are exactly correct. I was being lazy in not giving a full and complete answer. Mea culpa.
 
Take a look a look at the spark plugs. A good way of finding out what is going on.
 
Surely you can't just put a carb in an expect it to be cleaned, it'll need stripping to its component parts and then checked carefully on reassembly.

Exactly why I said what I did about ultrasonic cleaners.
I've cleaned and sorted carbs that have stood with petrol in them for decades, including some that have become spider nests as well.
If you're stripping every component in order to use an ultrasonic bath, and checking afterwards, and still having to blow through the air passages, the bath really isn't needed at all.
It's just yet another modern day gadget that the lazy and gullible think will work like a magic wand.
You don't need one.
Do it yourself, do it properly.
 
fresh fuel in the tank - open the carb drains and keep turning it over till it starts....then close the drains.

leave it on choke till it only just rns then bring the revs up until it clears then keep revving it till it gets to op temp.
 
fresh fuel in the tank - open the carb drains and keep turning it over till it starts....then close the drains.

leave it on choke till it only just rns then bring the revs up until it clears then keep revving it till it gets to op temp.

I recently fired up my Honda CB1100R after 15 years, using a Sealey slave fuel tank and fresh fuel.

Float bowl off, revealing clean carbs - I expected them to be gummed up, but no. The fuel tap had been turned off 15 years ago and I can only assume what was left in the carbs had evaporated - there's a fuel rail breather pipe on mine.

New battery, plugs - kill switch off until the oil light went out - kill switch on and off she went.

I'd bypass the tank for now and see what happens.
 
What sort of fuel tap is there on the tank? Has it got a vacuum valve in it? If so check or bypass that and give it a try.
 
The Latest

Replaced the fuel and cleaned the filter. She will now start and run a bit smoother than before and also does not cut out when I give it some beans. She will still not run when the choke is off. There is a vacuum valve on the fuel tap but it appears to be ok.
I guess there could still be a bit of shit in the carb somewhere.....
 
The Latest

Replaced the fuel and cleaned the filter. She will now start and run a bit smoother than before and also does not cut out when I give it some beans. She will still not run when the choke is off. There is a vacuum valve on the fuel tap but it appears to be ok.
I guess there could still be a bit of shit in the carb somewhere.....

Carbs off again and go through the pilot jets and emulsifier tubes very thoroughly.....especially the sideways ports in the tubes....look through carefully to check all are unblocked.
It's often said that you shouldn't poke through a jet in case you scratch it and alter the size, but I've often used a wire strand from a wire brush with total success and no problems after first spraying the removed jets/tubes with carb cleaner.
Blast carb cleaner through all the air passageways and ports and look for the spray emerging wherever the port/passageway leads to.
Mind your eyes, by the way....wear safety glasses.
 
Check the resistance of the plug caps, if high/no continuity, they can give all kinds of running issues. It may not be the issue but is a quick, free check & simple fix.

I now make it a service check on any older bike I buy, invariably they are out of spec (normally 5k ohm), ironically, low mileage bikes that have been stood are the worst.



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