urgent broken down in France help needed

[Whealie]

Monsiour La Honda in Grenoble was unable to diagnose this so maybe you lot can help as I will be in another garage at 8am (7am your time).
Bike went like a rocket all the way down. Sat Nav recorded ten hours moving and, including getting out of London and all the motorway stops, an average moving speed of 70mph. Top speed was a ton. Indication of a problem was very high fuel consumption, even allowing for the speed with luggage.
Went up the Stella no probs and the 35mile off-road trip the following day. But on that second trip, at altitude, the bike was running a bit rich and not liking higher revs. Got better lower down but still not right - a bit hiccupy when trying to give it welly (to keep up with Rob).
So, we stripped her down. Well, XRV Jim and piguglyshandy drinker did (thaks to both of them) and cleaned out the choke, making sure it wasn't stuck. The cable looked too short, as if it had permanently been pulling the choke on. So, once freed, we left it disconnected. The temperature is warm enough to start no probs anyway. The plugs were black with soot.
Still had misfiring problems at about 4000 - 5000 revs. so I left the others to start heading home, in case I was going to take a long time. The road to Grenoble was so twisty that the 60mph top speed I was now achieving was OK. Got to Grenoble and the assistance company booked me into Monsiour La Honda. I stripped the bike down again for them (honestly they didn't lift a finger until I had the plastics off and the tank off). They looked in the carbs, ran the engine a bit, turned a screw here and prodded things there, muttered in French and told me to put it all back together again as they couldn't work out what was wrong. They gave me some stuff to mix in with the petrol. I went to refuel but it was still not right so I returned to find the garage all bolted up and shut. Merci!
So I headed north.The bike deteriorated. I was getting a top speed of just over 60mph to start with but only mustering 50 uphills (and being overtaken by caravans). Then it started stalling when I stopped. Then the problems kicked in at lower speeds and I crawled on at 50mph, heading to yet another Honda garage. I never made it.
Havings topped for a drink, she just sounded awful when I restarted her, blew clouds of black smoke everywhere and coughed onto the slip road. I stopped before getting on the motorway and wheeled her back, calling the recovery people out to rescue me.
Basically there's loads of black smoke, sooty plugs and it coughs and splutters and misfires at about 4000 revs. And it is getting worse.
Any suggestions anyone?

[Whealie]

40 people have read this post. Nobody has replied. Is it really that weird nobody knows?

[romeo one]

check the air filter,and see that you have a good flow of air,it sounds that it`s far too rich.
hope it all turns out alright for you.

[Cie]

Sorry mate, no idea... you have european recovery?

[reme59]

if you have traveled 30 odd miles off road check the air filter

[Whealie]

you have european recovery?

Oh yes. If you own shares in AXA, sell them now. I'm about to break the bank.

[Whealie]

check the air filter

Changed air filter 2000 miles before trip. It is dirty already but Monsiour Le Honda looked at it too and did not suggest replacement.

[DaveS]

Well stating the obvious and logical the fuel mixture appears to be way too rich.

So what are the likely causes of that.
Choke - Already been checked.
Carb Diaphragm - Could it have a split in it?
Fuel pump - Pumping too much fuel?
Air filter - Blocked - Already checked.
Some other bloackage on the air inlet tract.

Does it run better with the filter out? Confirming a too rich fuel problem?

I'm not a mechanic..... but those are my logical suggestions from what I've gleaned over the years.

[chronyx]

Coil pack giving up?
CDI Failure? ( )

Can you see how good the sparks are?

[reme59]

plug leads! or sticky float