Hello everybody. New member here :)
I imported an '87 1VJ this spring from Southern France and am having some difficulty with the choke/carbs and wanrted some advice before I tear everything apart.

The previous owner said he had the carburettors "rebuilt" (I can see some new shiny parts on it) but I have no idea what they put inside it as far as jets go etc. I live in Amsterdam and it's been in the mid to high twenties celcius here ...The bike had starting issues but I managed to get it to start reliably by playing with choke settings: I found that if I barely pulled the choke out (less than 1/4 of the way) I was able to get it to fire up but the idle was too low and it would stall. I turned the idle screw enough to get it to rev higher but when the bike was fully warm the idle would be too high and I'd have to readjust it again when riding. My compromise was that I reset the idle screw for lower idle and I'd start it and hold the throttle open a bit until it was a little warmed up before riding. Not ideal but manageable.

So I have a couple of questions for those far wiser than I:
Is it normal for the 1VJ to need barely any choke to start in the summer? (my '91 xt600e needs full choke to start all year round) or is this a symptom of running too rich?
Secondly; is it likely a worn choke plunger rubber or possible weak spring ie; constant fuel leaking in past the choke plunger? Or even perhaps the choke cable tension freeplay setting being off?

So far I did try turning the main mixture screw clockwise a full turn to try and lean-out the mixture but it didn't really seem to make a difference with the choke settings ( I still could only start on less than 1/4 choke)

Any advice would be greatly appreciated since if I don't manage to fix the issue by adjusting settings I figure my only option is to buy an all new rebuild kit for the carbs (and probably also the choke assembly) to ensure I have everything back to stock and properly functioning ... which might be a waste if it's not really necessary.

Cheers - Julian

Check the choke easily enough. Can see down the top of the carb with the tank and air
Box off. Take the top off and you can see the hole for the air. Also take the rubber off the choke and see if you can measure the distance to plunger, then disconnect it, push it all the way in and see if there's a difference. For setting the carb up, you could disconnect the choke and push it all the was closed then see what she runs like.
I for one would still then pull the carb and check it myself on the bench. Standard jets unless you're on a race can, in which case probably go up to 48 on the pilot jet. Main is 140/145/150. 125 secondary. The fuel height is critical. Make sure nothing is sticking in the float bowl, then adjust float height to give you the 6-8mm below gasket level when running etc. A mm makes a difference.

Thank you Donny, this is exactly what I needed. I'll give it a shot next time I have a few days off and hopefully something obvious shows.