OK, so what is causing this oddness? Running a bit funny.

[Bibio]

iridium plug gaps go out quite easily...

hows your battery for health?

also try tapping the float bowls when you are out and it happens, see if that helps.

are you sure that the carb heaters are coming on and no loose wires or corroded connectors..

[northwind]

Won't be carb heaters, some territory bikes come without them and they do fine (and this isn't carb icing weather, it was scorching today!) Battery should be OK

The trouble is, it'll only do this in the midrange and under some load, and unpredictably, so I can't recreate it in the garage. Bit of a pain that, a lot of the usual diagnosis tricks don't work. I can ride around it at least (actually, in some ways it's quite good, I'm a lazy rider and I tend to do too much riding at lower revs, now I can't!)

[Bibio]

it really really sounds like a sticky float.. or a bit of crud floating about inside float bowl..

[northwind]

Bowls are as clean as I can make 'em without a sonic cleaner... Floats seem to be moving fine, but then they would since the bike works absolutely fine for 99% of the time or more, the chances of it sticking just when I'm checking are slim I guess. But yep, the explanations that made most sense were slide diaphragms, dirt in the carbs, a float issue or the emulsion jet being worn, and that's probably still true.

Sod it, new carbs time, it's not worth spending any more time messing about on since I've got all the parts anyway. And it should fix any of those 4 at a stroke.

Thanks for all the feedback folks... I'm pretty handy but I do sometimes overlook stuff so it's really useful to have you watching over my shoulder.

[Dave20046]

Originally Posted by Bibio

iridium plug gaps go out quite easily...

Got to admit I did neglect to gap my new plugs, they weren't too far off what they're supposed to be though IIRC. Can it make much difference (before they go completely out) can't say I've even noticed tbh

Originally Posted by northwind

Bowls are as clean as I can make 'em without a sonic cleaner... Floats seem to be moving fine, but then they would since the bike works absolutely fine for 99% of the time or more, the chances of it sticking just when I'm checking are slim I guess. But yep, the explanations that made most sense were slide diaphragms, dirt in the carbs, a float issue or the emulsion jet being worn, and that's probably still true.

Sod it, new carbs time, it's not worth spending any more time messing about on since I've got all the parts anyway. And it should fix any of those 4 at a stroke.

Thanks for all the feedback folks... I'm pretty handy but I do sometimes overlook stuff so it's really useful to have you watching over my shoulder.

out of intrest has you bike been smelling of strong petrol when you have finished your trip ie when parked up

[northwind]

Nah, no different from usual.