Still not running right

[tony.mon]

Doesn't sound right, but too many possibles to say for sure.
Possibilities include:
CCT-induced valve bent
Small ends
Broken ring (less likely)
Mains or big ends
A shaft bearing, gearbox bearing
clutch bearing
Someone's removed the "quieting gear" on the primary drive gear- (shouldn't affect engine power, just makes it noisy at tickover)

A compression test will help.

[Karl_h]

Just been down and had a fiddle and attempt to balance the carbs. Found another problem the choke was getting trapped and the routing of the cable wasn't right. Should the cables go around the outside of the carbs?
Just got a quick reading from the carb balancer and they were well off, rear cylinder wasn't registering at all so might be miles off. Got dark and ran out of time so parked it up till the weekend.
Slightly dubious about it being cct related as it ran fine before the carb cleaner and filter swap. Could any of the other symptoms happen rapidly or would I have noticed it happening over time. This happened straight away, as soon as I ran it up with the cleaner and filter on I knew something wasn't right. Also the ride home from its winter hiding place was fine so its not where its been stood.

More questions than answers. Going to sort the balance and choke out this weekend. After that I'll sort out a compression test.

Cheers for the input.

[benny hedges]

look in the pdf manual in the workshop section... theres a page that shows the cable routing

if the choke isnt seating properly it will run like a bag of crouton.

[Karl_h]

Argh just been looking at the manual but only went as far as the fuel section.

Cheers for that

[AMCQ46]

with the fuel consumption way down, I would look again at the choke cables or plungers as a 1st point, and they are lower cost fix than any of the others.
Would worry that one pot was not regestering any vacumn on the carb balance, as unless you seperated the 2 carbs when you stripped it down, they should not get that far out of sync so next stop is compression test to see what the valves are doing.

[tinysmall]

Might sound silly but have you had a good look in the tank recently? My bandit developed a rusty tank and that gave the symptoms you've got. I had to clean and balance the carbs every day till I cleaned the tank with nuts, bolts and paraffin and put an inline filter on it. Choke cable does sound a likely candidate for investigation though.

[Karl_h]

Think tank is ok. When I took the carbs apart there was a few bits of dirt in there but nothing to make me worry about the tank. Hoping choke and carb balance is all it is.

[tony.mon]

Disconnect the choke and try a different pair of carbs.
You can always sell them afterwards to get your money back.

[Karl_h]

Cheers Tony, I should perhaps point out that I'm a poor student so doing everything that's free first!

Also I hope I haven't but if it looks like I've just ignored peoples advice this is again just me doing cheap stuff first!

Also Tony what was your input on my queries regarding the possibilities you suggested happening over a short period?

Once again thanks everyone for the help

[tony.mon]

Any of the things I listed could have happened suddenly, and might have just happened (coincidentally) just after you fitted the new filter, but this is quite unlikely.

So the chances are that you disturbed something when you played with it, over-oiled the filter, knocked the carbs or otherwise adjusted/disturbed the balance, but the lack of vacuum is a concern, best find out why that is first.

[Karl_h]

Right I think it's fixed! Haven't had chance to ride it yet as I managed to give myself a little bump on the head due to the bike deciding to have one last bit of drama, and haven't felt quite up to it yet!

After my latest mishap with the chokes I bypassed these and put everything back together. It sounded healthier straight away. So I set my high idle for the bike to warm up and so it was ready for the carb balance. Nipped to the shed to grab a spanner for the rear carb adjustment and after a minute or so I hear a little cough, followed by the idle shooting through the roof! Running out of the shed a bit quick I managed to put myself on my butt and collect a lovely bump on the head for my troubles!

Ran round to the bike to find revs nearer 7000 than the 2000 I had left it at and the street rapidly filling with smoke! wound the idle screw back to virtually nothing (it was probably more than halfway along its travel, strange that it only becomes apparent that it probably isn't right at a time like this) and the bike purred away at a nice steady idle.

Waited for a bit of fathers judgement as to what to do with the smoking situation, left it running for a bit and everything cleared!

Carbs now balanced and its honestly sounds ferocious, I'm a little nervous about riding it! Strange this must have been a fairly old problem as I hadn't really messed with the idle screw other that a quarter turn here and there so for it to need the massive adjustment that it did is surprising, I guess this means the pilot jets were blocked????

Proud of my mornings work I switched the bike of and went to leave the garage as I turned to shut the door, I noticed a large puddle of coolant was appearing on the floor, guess I hadn't checked absolutely everything! Oh well at least it'll be an easy fix.

Thanks to everyone for all the help! Much appreciated!

Karl

[tony.mon]

Chances are that the smoke was coolant from the leak burning off from the hot exhaust pipes, so that should clear and not come back once you've found the leak.
Probably a loose pipe clamp, suggest it might be the short hose from the thermostat housing to the front cylinder, as you may well have had to disturb that to get to the choke 2:1 barrel.

You won't have done any damage to the bike running it at 7K idle for a bit, at least not compared to your head!

[Karl_h]

No this was definite combustion smoke, the hose came off about an hour after the smoke and sudden jump in revs.

It must have been a blocked jet that's gradually got worse as the idle screw was well over half way and now is pretty much at its lowest setting.

You were spot on with which hose though Tony, luckily could get to the clamp without taking the carbs off!

Have taken the bike out quickly now.
The difference is incredible, its never been like this, it constantly wants to lift the front, going to take some getting used to!

The head is another story, stings a bit that's for sure

[tony.mon]

It's always that one, hardest to get to, that's why......

If you're right and a jet unblocked itself, then it may be that the smoke was just carbon deposits burning themselves off from the exhaust valves, stems and head.
Probably rings as well, so the thrashing will have done it some good clearing that lot!
You might try a cleaner type additive in the fuel for a while, but don't overdo it, remember that the instructions are usually for cars and their tank is a lot bigger, so when it says half a bottle per tank.........

And I'd suggest using good quality fuel for a few fills, that has detergents in that help to keep the engine clean internally.

Shell optimax is one, but other companies do their own versions.