recognise this spring?

[pae]

just in-board of the LH carb in this picture, there's a spring laying on the bench (an odd one with a hook, coil, straight piece, another coil and hook at the other end). Does anyone recognise it? It pinged off from around the choke linkage area when I dismantled the carbs and i can't work out where it came from. I'm nearly finished rebuilding them, and with everything nice and clean I can not see where this could fit.

Now, it may of course have fallen from somewhere else and just made its home for many years buried in dirt, grease and oil. My manual doesn't show a spring like this in the diagrams.

regards, Phil

[Volker_P]

Sorry I do not remember this spring, however it has been years that I separated carbs for changing the O-rings of fuel tubes.
So I start guessing a bit instead : I think this spring looks too weak to move or hold anything outside the carbs. It rather reminds me to the mechanical frequency adjusters and displays of old radios where you often find similar ones, however with more windings.
I will try not to forget to pick a carb out of a box and have a look.

[pae]

Thanks Volker, as I say, I can't see where it would go, and you are right, it is a very weak spring, although the 'connection' between the two halves of the choke is not very firm. But I suspect it's something that lodged in the oil and dirt just to catch me out and doesn't belong anywhere near this assembly.

regards, Phil

[old gringo]

Looks something like the spring from the stoplight switch.

[Volker_P]

I had a closer look at two carbs out of the box and did not find a spring of this size. So I think you are right that it is from elsewhere. I do not remember that I ever saw a spring like that on my CB. But well, I'm old.

[pae]

Looks something like the spring from the stoplight switch.

Yes, it looks similar, but this spring is tiny compared to the stop light one.

I think I'll put it in my box of 'useful bits' and not worry about it for now. One day I'll find a use for it.

regards, Phil

[Ibsen]

I think the spring is connected to the fast idle cam for the choke mechanism:

http://cosky0.tripod.com/imagelib/siteb ... et=tlx_new

[old gringo]

I think Ibsen is on the right track. I wasn't able to check my carbs as they are in Texas getting rebuilt

[chucksklrst]

Where in Texas did you send your carbs. ?

[pae]

Hi Ibsen, are you looking at the one up top-right of the diagram? Near the throttle mechanism? I think it pulls the acclerator pump lever onto the cam.

If so, it's not that - I have that one in place already.

regards, Phil

[Ibsen]

As I said; I think, since I wasn't quite sure.
And I really didn't want to dismantle mine to find out.

old gringo, did you send them to Mico, TX?

[chucksklrst]

What would the symtom be if that spring was missing. I have having a very hard time setting my choke to the factory 2000 rpm. with choke pulled all the way out bike will run at 1500 than race up ro 3500. my bike runs and starts great but the choke is all over the rpm scale. Don't mean to hijack this thread. Thanks for any insight.

[Ibsen]

Jumping from 1500 to 3500 as it warms up just after a start up seems pretty normal.
You can adjust the fast idle cam and that way lower the rpm when you are using the choke, but if you lower it too much the engine will choke itself and stall just after it has been started with full choke, especially in cold weather, or it might not start at all. Another problem is that the fast idle cam has to be adjusted when the engine is dead cold, and the adjustment screw is very small and you will have to take off the fuel tank to get to it.
Instead of adjusting the fast idle and maybe not get it right, the best to do is to push the choke knob gradually down as the rpm rises and try to keep it at 2000~2500 during warm up.

[old gringo]

Sent them to wgcarbs (wiredgeorge) in Hico, Texas. http://www.wgcarbs.com/

[Volker_P]

Jumping rpm's during getting warm often come from cylinders going on and off. Mine usually starts on two and runs on four after 30s. If the time is much longer and you don't like that, you can try new plugs, check ignition and valves and a carb synchronization (in that order).
I took a picture, where the red arrow indicates what I think is the the spring in the schematic provided by Ibsen above. It looks larger. The choke mechanism seems to have only the two circular springs on the cam.