If you fitted the new shaft seals as per the image then they will not be leaking. They have to be fitted backwards.
Try the WD40 test to eliminate the air leak possibility.

Thanks Blair. I did read through your strip down/service guide on your web site a couple of times & took notes, so yes, the shaft seals were fitted as per the photo above. Did you get my order & payment for a GK76 "seal kit A" & a Viton fuel tap to tank seal today ?

As for an air leak, is it possible one (or more) of the new OEM jet holder to carb O section seals have been damaged by the locating pips in the seal grooves on the jet holder & that's how excess air is leaking in & affecting the vacuum and/or mixture ??

Yes, received your order thanks, and it is going out in today's post.

The only issue with jet housing seals is that you could be unlucky and get one that is too thin. Rubber parts that size are usually about +/-0.08mm
I have mine made 0.05 to 0.10mm thicker than standard. Then I measure each one before packing to ensure that they are within tolerance.

When you say it goes out of balance is that something that you have measured?

Thanks again Blair. Hopefully this order is delivered in 5 days too. Will let you know when it arrives.
If you watch the video link I posted above you'll see exactly what happens every time I have them balanced.
If you're really bored & have 9 minutes to spare that is ...

No. 1 cylinder is always the worst at 1100-1200 rpm. Richening the mixture only improves cyl. 1 slightly, hence why I think there's an air leak somewhere ... but I'm no expert with CV carb's.

Right, time for bed as it's 01:15 here in the UK.

Bye for now.

It is not possible for me to watch the video because it says that it is private.

Apologies Blair. My video link has now been "unlocked" & made "public". If it's still "private" someone let me know as there must be a problem with the link. (It's the first video I've uploaded to YouTube ).

https://www.youtube.com/watch?v=I4gQdmkRZ0E

EDIT : Like this, Blair?

I think you have to click on the URL button above and inset your link between the two tags.

Think it's all sorted now. See previous post By the way, don't you sleep??!!

What is in those tubes?

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