Carb question.

[ColourNcoat]

Daft question: you have got the choke slider lifted up?

Yes the choke slider is up and working fine....
After a complete strip down and cleaned with cleaner and all blown through with airline.
Started like a dream but then same as usual. I then took the plug out and it is getting fouled up.
The oil control screw was missing so had to make one. The bike is smoking a bit but not in excess and I'm wondering if this could have been the problem all along?
I have seen discussions on this saying it will smoke like he'll if the screw was out too much.
The screw should be about 1/4 to a 1/3 of a turn out. Could this be my problem?
Where can I get one if this is the case?
Cheers for sticking with me

Do you have the correct taper on the new screw?

Hi Duncan, I don't know...I made one for it with a sharp taper and then with a shorter taper.
Regards.

[SPRIDDLER]

The inlet valve oil metering screw should look like this.......
An eighth of a turn open is normally sufficient.
Less than a fiver from club spares
http://www.amoc-parts.com/store/comersu ... duct=20917

inlet valve oil dims 009 (740x555).jpg

[ColourNcoat]

The inlet valve oil metering screw should look like this.......
An eighth of a turn open is normally sufficient.

inlet valve oil dims 009 (740x555).jpg

At the risk of sounding like a broken record - have you checked the valve clearances?

I set the valve clearances only a few days ago after re-tightening the cylinder head and sealing the rocker cover.
As for broken record it could be something I've missed
The picture is great with the sizing.
All is helpful
Regards
I just tried to order one and my Internet browser not accepting cookies so will order one thanks.

[clanger9]

What size idle jet are you running?

[ColourNcoat]

What size idle jet are you running?

I did write them down when I took carb apart.
They were listed on earlier page 2/3
The pilot jet is a 20.
Thanks
Sorry Clanger I didn't mean to sound ungrateful then

[ColourNcoat]

The inlet valve oil metering screw should look like this.......
An eighth of a turn open is normally sufficient.
Less than a fiver from club spares
http://www.amoc-parts.com/store/comersu ... duct=20917

inlet valve oil dims 009 (740x555).jpg

Looking at the picture ( the one I made ) the thread goes all the way to the taper.
The one in the picture goes half way then the OD reduces before the taper.
As my thread goes all the way this could be stopping the screw from going in far enough

I did manage to order a new one last night so this ( may ) have been my issue.

Will make new one today and see what happens ( can't wait ) for the post lol.

Look forward to posting findings

[clanger9]

What size idle jet are you running?

They were listed on earlier page 2/3
The pilot jet is a 20.
Thanks
Sorry Clanger I didn't mean to sound ungrateful then

My apologies - I missed your earlier post.

Symptom: starts, but chokes after a few minutes, apparently running rich.
Checked: float level OK, idle jet OK, choke OK, tappets OK.

I'm running out of ideas!

Jet block gasket?? It's part 376/067 in this diagram:

39amalmono.gif

[edit: corrected fat-finger typing of part number...]

[Mick D]

Jet block gasket?? It's part 376/076 in this diagram:

Finger trouble it's 376/067

But to be honest it's unlikely to be the cause - if it were damaged the problem would be there immediately on start.

When the engine is struggling to run do you see black smoke from the exhaust?

For the inlet valve oil screw to be the culprit the spark plug would have to oil up, is this the case? you would also see blue / grey smoke in the exhaust.

Another thought - have you replaced the jets or are you relying on them being unadulterated by a PO? '20' on the pilot jet means b all if it has been cleaned with a drill bit or gas torch file

Regards Mick

[clanger9]

The fact that it's completely insensitive to the pilot mixture setting suggests it's running on the main jet, not the idle jet. (?)
Hmm...

[Mick D]

The fact that it's completely insensitive to the pilot mixture setting suggests it's running on the main jet, not the idle jet. (?)
Hmm...

My thoughts are leaning towards muck in the pilot galleries intermittently blocking them. Can't see that it's running on the main as the needle will be closed.

The flow rate of the pilot jet can be checked with a bit of 'Heath Robinson' equipment, it should pass 20cc / minute but if the jets haven't been replaced I get a new known good set.

Regards Mick