main jet problem

[dant-40]

Hi guys,
Third cylinder wasn't firing on my 1978 gs 1000. So after stripping carbs, I found the main jet lying in the float bowl. I put it back in and after riding for a few days same problem again. Anyone experience this before and if so what is the solution?
Thanks in advance.
Dan

[hampshirehog]

Yes - seen it a few times (and sometimes the bike will ride fine as long as you don't use full throttle). First off try swapping the main jets around and see if it happens again. If it does and it's in another carb then buy a new jet. If it's in the same carb you can either stick the thing in (Araldite) or get another carb - as the threads are cream crackered.

I presume there isn't any forcing of the thread going on and that you can see a thread in the offending carb or on the offending jet.

[dant-40]

Hi hampshirehog.
The threads are ok. Screw went in fine. definitely not a damaged thread problem. I was thinking it might just be vibrating out.
Dan

[Octain]

The main jet vibrating lose. Holy cow!
Sounds like you have some other issues if that's the case.

I think if it vibrated that much you'd notice it.
Has the bike had a resent valve adjustment?

[hampshirehog]

Hi hampshirehog.
The threads are ok. Screw went in fine. definitely not a damaged thread problem. I was thinking it might just be vibrating out.
Dan

It probably is just vibrating out which means that there is something wrong with a thread that you can't see. Pass on why it happens but it does and it shouldn't. I would try swapping the jets around and see what happens. You might not find the cause but you might find the cure.

[dant-40]

Thanks octain and hampshirehog for the info.
I'm away for a week now so I will have another look when I get back. I will try swopping the jets and also check the valves.
Dan

[MisterCinders]

Yes - seen it a few times (and sometimes the bike will ride fine as long as you don't use full throttle). First off try swapping the main jets around and see if it happens again. If it does and it's in another carb then buy a new jet. If it's in the same carb you can either stick the thing in (Araldite) or get another carb - as the threads are cream crackered.

I presume there isn't any forcing of the thread going on and that you can see a thread in the offending carb or on the offending jet.

Whoa. Rhyming slang spotted.

[Octain]

Thanks octain and hampshirehog for the info.
I'm away for a week now so I will have another look when I get back. I will try swopping the jets and also check the valves.
Dan

Keep us posted!