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Smoothbore carb gasket?

S

steve murdoch

Forum Guru
Past Site Supporter
My first time taking apart the 29mm smoothbores. Previous Owner Syndrome has not been kind to them.
The brown wafer thin material at the bottom of the carb body has started to fall apart. Mikuni calls it a "Jet Block Gasket VM29/13".
Z1 Enterprises does not carry them, any other sources?
Suggestions on how to remove them with out scoring the body?

P1060876.jpg
 
Sudco should have them. http://www.sudco.com/Diagrams323728/expvm29.gif
I'm pretty sure that's where Z1 gets their smoothbore parts.


I made some of those jet block gaskets once out of stiff velum type paper. Tested the paper by soaking in gasoline for a few days first. Worked fine.
 
Thanks for the replies, gents.
A bit more searching and i found them at Jets R us for $3.95 or Motorcyclecarbs.com for $9.95. Yikes!
I will contact Jeff at Z1.
I am assuming they act as a cushion for the jet block?
 
We have them in stock. SU002-535 - $1.85 each.

Without those gaskets, the pilot circuit fails to pickup fuel effectively - making for a frustrating experience trying to get the bike to idle properly.
 
Steve..just a reminder here. Dont forget to poke all the holes out in the bleeder tubes. You can even gently twist them and remove for cleaning. Put them back in the holes and then tap them back in firmly with a fiber mallet. Then repoke the tiny little hole on the end to be sure any fiber didnt get in there ( usually doesnt though ).
 
Thanks to all that responded to my question.
Along with the usual great parts/info supplied by Jeff and Chris at Z1, the complete rebuild of the smoothbores has been completed.
Ultra-sonic bath, dipped, guitar stringed, tooth brushed, air blasted, o-rings, gaskets...in a couple weeks they will be tested.

P1060888.jpg
 
Steve, your PM inbox is full, was messaging you this:

In reference to THIS:
steve murdoch said:
Thanks to all that responded to my question.
Along with the usual great parts/info supplied by Jeff and Chris at Z1, the complete rebuild of the smoothbores has been completed.
Ultra-sonic bath, dipped, guitar stringed, tooth brushed, air blasted, o-rings, gaskets...in a couple weeks they will be tested.

P1060888.jpg
Click to expand...

WOW... you made no mention of the bike model these were for, but they appear to apparently be for the 6 cylinder Honda cbx (I believe they were called)?

I have never heard of such a rack of vm29 smoothbore for the six-cylinder Hondas! is this what they were intended for? Was that something that you custom assembled yourself using two sets of 4 cylinder carbs? Or was this actually from Mikuni intended for those bikes, or previously custom made for a six-cylinder race bike?


part of me was just curious about this as I have never seen a 6 cylinder rack of smoothbores.

then a light bulb went off in my head! if you built these custom for a six-cylinder application, do you happen to have the remaining two outside carbs? I was likely going to have to get a set of Keihin CR31 or CR33 smoothbore carbs for when I build up a highly modified gs425 2 cylinder engine into a 475cc 10.5:1 race engine with head work, JE Pistons 894cc GS850 custom pistons, head work by RapidRay, megacycle cams, etc...

I thought about putting CR carbs on the Rickman with an 894cc gs750 engine, but I had reservations that now I needed to stock a full set of Keihin tuning & rebuild parts, when I already had everything for Mikuni VM's. well I just got a set of VM29 smoothbores as a thank you gift, and thought that it would be really great to be able to assemble a rack of vm29 smoothbore for a 2-cylinder GS as well to eliminate the need for any other brands of motorcycle carb tuning / repair parts. I was just curious if you had the two outer carbs if that was assembled custom from two sets of carbs. I know it's been 4 yrs and you likely may have just come upon them in their current state, or maybe that is their original state.

thanks Steve,

Chuck in Columbus Ohio
 
Chuck, i finally cleaned up my inbox.
The carbs came already fabbed up. They were built by a guy named Rick Chupp. He was a smoothbore carb guru for the vintage race guys about 20 years ago.
Last i heard he was working in Indiana someplace. Cycle Outfitters or a name something like that. Pretty sure he has long retired.
The carb to head manifolds are very difficult to find these days.
I still haven't used the ones from this thread. Sold that particular bike with stock carbs.
 
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