Hi All,

I was in the process of balancing the carbs and struggling to access the screw between carbs 3 & 4 (RHS) when I noticed that the tiny brass transfer pipe (about 2.5 - 3mm diameter) has broken where it goes into the carb. Any idea what this does, what the effect of it being broken would be and if there's an easy fix?
The carbs have new o-rings all round but it seems still have been running a little rich.
Image shows the same pipe on the next carb along.


cheers for any help!
James

I think it is the fuel transfer pipe for the choke. The fuel jets out of the top of the carb when the choke is operated. You should get it fixed as it may leak neat fuel on a hot engine.
Unless you can get an engineer to fix it, you may have to resort to replacement carb/s

There's good chance that any workshop doing air conditioning installation and/or repairs will be able to fix this. Unfortunately you'll have to disassemble the rack to fix this. If you manage to get the line itself I think that it is DIY doable repair.

Always ensure that there's no fuel anywhere in carb when doing this kind of repair. Fuel anywhere near flame or electrical soldering unit is the very last thing you want to deal with.

Thanks for the responses!!
Indeed it is part of the choking system - the lever operates a valve of sorts. This seems to seal the hole well with no visible leakage. To ride or not to ride?
I'm in Madeira so limited local help, will try to source some carbs on the mainland.
Cheers,
James

Wow gorgeous place to live and must be a great place to ride. If there's no engineers on madeira try ebay uk for spare carb parts as ebay now has cheap international shipping program. If it doesn't leak you could risk it but remember that if too much fuel hits the exhaust its very dangerous.

Hai I just read your post and the easiest way that actually works well is a product called pratley steel, it consist of two parts which you mix together and it will bond to almost anything and when set it hardens up like steel!
Hopefully the product is available to you, I've used it to repair cracked carb float bowls, and even leaky tire valve!

Good luck!

good idea! I've actually fixed fallen nose from one carb some time ago and it holds till now. it is little bit messy work but might work! if you can't find that specific brand, ask for "liquid metal". you have to clean the place thoroughly and be sure that there's no grease nor fuel.

I've got quite a few spare carb parts. I'll have a look if I have this part. If you pay for postage you can have the part for free.

Christian.

I had the exact same problem on a GK 76A.
Mine was mechanical damage to carb no. 4 and thus was repairable without dismantling the carb bank.

The pipe appears to be the air supply for the choke circuit and is closed when the choke is applied.
No fuel ever leaked from mine when detached.

The brass pipe was totally dislodged on my unit.
I cleaned up the carb orifices and the pipe ends and then refixed the tube using a two part "superglue" with filler "dust".

It does not appear to be a critical part of the starting circuit if only one carb is damaged......my bike started and ran without the pipe fitted....it just took a few seconds for the affected cylinder to chime in when starting from cold.

Since the repair it starts straight off on the affected cylinder when using choke.

It is not a spare part for the carb and appears to be cast/pressed in when the carb is manufactured.

Thanks all for the advice. It's pretty warm here (never less than 16 degrees in the depths of winter) so haven't needed the choke. Runs better than ever since I balanced the carbs and not leaking but I would like to sort it.
Thanks for the offer Christian but as Willandrip points out it does seem like a pressed part.
Will go down the glue route for now and seek a spare set of carbs.
cheers,
James