Poor running on front cylinder - Curvy.

[andrewsmith]

Start at the carbs and the rubbers.
Smear a tiny bit of RRG around the rubbers helps them seat better. When you put the airbox on, take the filter out and offer it and work them properly from the inside.

Check the fuel lines aren't kinked also.

Going to put the one Rictus suggested to me with the crap running. Clean up the coil connections and blast the HT end with contact cleaner or change it, then apply Vaseline to the coil pack ends

Originally Posted by Bagpuss

Remind me not to get on a plane you've worked on then

Why would you say that? Have you been lucky enough to always find mechanics who quickly and accurately diagnosed problems, then fixed them, properly?
I've run into mechanics like that, quite a few of them, but I've also run into a lot that made things worse, or caused some new problem as they repaired the original problem.
I learned, when you hear "I just replaced/cleaned/repaired" some part of a mechanical device, and a different problem has suddenly appeared, the best place to start looking is with what was repaired or replaced.
That's just a simple good sense lesson.
As to my actual mechanical skills, you know absolutely nothing.

Originally Posted by embee

Check the carb is sitting in its rubber correctly, the clip is tightened properly, the rubber isn't split, and the cap isn't missing off the vacuum tapping used for balancing (front right hand side of inlet stub).

Seemed to be sitting fine, and clip tight. Rubber of the duct feels OK too - I don't really want to try and remove it to examine better as screws don't feel like they going to go - unless I need to take them out?

Originally Posted by wideguy

Did you do what embee suggested and make sure you had no vacuum leaks into the front cylinder?
Any time the carbs are removed, there's a chance they won't properly seal into the intake boots on re-installation.
It's worth looking at the idle jet, but only after you are positive you have no vacuum leaks.

Yep. Checked as best I could with them in place then removed the carbs to check the ducts. Is it worth sticking them back in again to rule out a bad seal before trying to strip the carbs?

Originally Posted by andrewsmith

Start at the carbs and the rubbers.
Smear a tiny bit of RRG around the rubbers helps them seat better. When you put the airbox on, take the filter out and offer it and work them properly from the inside.

Check the fuel lines aren't kinked also.

Going to put the one Rictus suggested to me with the crap running. Clean up the coil connections and blast the HT end with contact cleaner or change it, then apply Vaseline to the coil pack ends

Will grab some contact cleaner tomorrow and, as above, try all this before stripping the carbs.

[Bibio]

while you have the carbs out check the pilot screws to make sure i set them again after cleaning.

ooohhh and he forgot to mention the bike cuts in and out of 2 cylinders when heated up. i also noticed that the exhaust gasses where very very hot.

[andrewsmith]

Originally Posted by Bibio

while you have the carbs out check the pilot screws to make sure i set them again after cleaning.

ooohhh and he forgot to mention the bike cuts in and out of 2 cylinders when heated up. i also noticed that the exhaust gasses where very very hot.

Fuel or coils by the sounds of that

Originally Posted by Bibio

while you have the carbs out check the pilot screws to make sure i set them again after cleaning.

Wildo. What do I check they are set to?

Originally Posted by Bibio

ooohhh and he forgot to mention the bike cuts in and out of 2 cylinders when heated up. i also noticed that the exhaust gasses where very very hot.

Good point. Cold and at idle the engine runs mostly on 1 cylinder, with the second occasionally kicking in. Warm at idle engine runs mostly on 2 with the occasional drop to 1. Cold with a bit of throttle, runs on both.

[Bibio]

what book says. it's something like all the way in and 1/&1/4 out but the book will say. i dont have the mk1 manual to hand so don't know the turns.

Originally Posted by Bibio

what book says. it's something like all the way in and 1/&1/4 out but the book will say. i dont have the mk1 manual to hand so don't know the turns.

Book says 2 1/2. Rear was 2 1/4, front was 1.

I'm still going to clean up connections but will put the carbs back in without stripping as presumably that could be the problem?

[andrewsmith]

Test it
That wont help tbh!

sent from a weapon of mass distraction

Well, after adjusting the pilot screws and cleaning the contacts, it does seem a bit better. It's still not quite right and was threatening to cut out, but didn't, and the choke works more like it should.

This close to the GM I'm going to stop mucking about with it in case I properly break it. Once I'm back I'll try and adjust the pilot screws with the carbs in place - do you need a special tool? If that still doesn't sort it I'll strip the carbs again.