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etbike3135 wrote: those come out real easy with some heat. I don't think you have a problem there. A lot of times I take them out when I'm doing a carb cleaning. You just need to find some off a donor set.

Hey there etbike3135 - "with some heat" can you please expand on this? - ie how to apply the heat and how much/how long - don't want to turn my carb into a pile of grey stuff!

Use a heat gun if you're afraid of a small propane torch getting away from you. You can source the enrichener pick up tube off of most any VM carb that came on these bikes. Once you pull the stem out of the donor carb, measure the hole diameter. Now, you can carefully drill out the broken one in your carbs with a finger drill so you don't drill oversize. Go undersize with the drill bit and you can usually pick the last .005 of the tube out of the carb body with a pick. Be careful not to cut the hole getting the remnants out.

Ok- got me a little butane "pyropen" from fleabay for a few bucks. Gassed it up and applied heat around the broken bit of tube - see pic of carb body with broken choke tube.

Made a new choke tube out of some 3mm OD x 1.9mm ID brass tubing. Cut to length and drilled the 6X 0.5mm holes in the wall of the tube - 2 at 15mm from "free" end of tube and 4 at 26mm from the "free" end of tube. (Tried to load a scanned diagram of the measurements but nogo!) Anyway, here's a pic of the old and new tubes.





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Used a series of 3 eyelets to step the hole in the "free" end of the tube to the 0.4mm diameter. These are eyelets normally used for printed circuit board repair and I have kept some of these (might need them one day!) from when i was a micromin repair tech. A pic of the three eyelets to demonstrate.

It was "just" a simple matter of soldering the three eyelets into the tube. After tinning the brass tube I dropped the 3 eyelets (one inside the other inside the other) into the "free" end of the tube and applied a soldering iron to "sweat" solder the eyelets into the tube. I pushed a sharp toothpick into the opening of the smallest eyelet to stop the solder from filling the hole. Once this was done I put the new choke tube into the freezer until the next day and when I had heated the carb body up with the trusty pyropen, I was able to tap the new (chilled) choke tube into place.. Not quite identical to the original but I think it should do the trick.

Weales,

WOW! That's some handy craftsmanship.

missionkz wrote:

swest wrote: Those emulsion tubes have their own shaft they fit in. If you'll look at the others, you'll see a hole at the top. I don't think you'll have a problem with shorter ones but make sure you have the right size vent hole there. My 33's have a jet at the bottom of the shaft leading into the bowl. I cleared one of them and noticed a difference. Why? I don't know but I will make sure all of are clear next time I have my carbs off. .
Steve

Steve, I think he is only talking about the 1/8" dia, pick up tube for the choke enrichment system, not the emulsion tube on top of the main jet.
Well, do they call that pickup tube an emulsion tube also??

On my float bowls at the bottom of the chock circuit well is a jet. That's what I was talking about. I overlooked cleaning them out every time I had the carbs off until one day I spotted them. The next time I changed my pilots (on the bike) I cleared all of them.
Steve

Ok what??? Seriously impressive man. I had one of those tubes break off yesterday. Saw your post and began to feel hopeful. Then I read the solution:dry: . This is not a task for the moderately resourceful rider. This is a feat of ingenuity. Please tell me how a layperson would fix this problem

What was the effect it had on your bike. It being broken. Any suggestions on fixing would save me some stress for sure

I repaired mine using some brass tube which I got from an engineering supplies place here in Oz. I was able to get the remaining piece of tube out using some heat around the carb body (not too much!) using a small pyropen. I drilled the tiny holes in the new tube which i cut to size and reduced the size of the hole at the bottom of the tube using solder eyelets -being careful to not block the hole! I froze the new tube in a freezer, then when ready, heated the carb around the where the tube fits in and was able after a couple of attempts to pushfit the new tube. NB to all - the tube is not identified as a separate part so you won't get one from a mikuni/kawasaki dealer. Hope this helps. Also make sure you err slightly on the short side for your new tube otherwise the float bowl won't come up snug against the carb body and will leak!!
BTW I have sold my Z1-R to a bloke in Victoria who is enjoying his new toy! Bike had to go for next project which I now have after waiting 50 years to get it! It's a 1968 Norton P-11 desert sled. I know, sorry guys but I've always wanted one since they were first advertised in "Cycle World" back in 1967!

Hats off to weales for posting nice photos describing the fix. Good job.
I performed a similar fix on cracked tubes in the float bowls in some Keihin carbs. I rolled the end of the tube over using the dimple in a threading die but wasn't entirely satisfied with that solution. Soldering those inserts inside is an innovative solution, assuming they can be sourced easily in your local area.