Fuel connector tube between carbs

[jnnngs]

When putting together the carbs today, I was a bit surprised, how difficult it was to get the tubes with Randakk's o-rings inserted into the carbs. Almost as if the o-rings were a little too big. I sprayed some WD-40 on them, but it was almost impossible to press them into the carbs. I got carbs 4-6 together but I am already scared that I will mess up the connector tubes between the banks, since they are longer and curved. What am I missing??

WD-40 will cause (some) rubber such as o-rings to swell, so never use it as a lubricant - use ordinary oil.

[daves79x]

Keep a tub of grease on your rebuild table and use just a bit on each joint as you assemble. Randakk's (and others) o-rings ARE slightly oversized on purpose, but grease them and you'll have no trouble.

Dave

[oroepke]

Ok, thanks, will try oil/grease for the other bank.

[oroepke]

It was a good day today! Carb assembly completed and benchtested successfully! No leaks, all accelerator pumps work, choke moves freely! Thanks to everyone for their help!

[daves79x]

Congrats! A couple of things - you should probably have put at least the 1-2 and 5-6 bowl vent nipples on. OK to not use the vent Ts on 2-3 and 4-5, just another place contaminates can get in. Also, and you can fix this now - put heat shrink on the idle adjuster spring/screw. The spring part will rust quickly. Also, new JIS screw sets are cheap!

Dave

[oroepke]

All good advice, thanks! I thought that because I don’t have the T-piece I leave them out but you are right, 2 are better than none!

I will get into the carb again in summer when when I convert the jetting back to original and install the airbox (there are pods on there now) and will replace screws then.

[oroepke]

Two random question for the brain trust:

I can see from Mike Nixon's book that it can be quite a bit fiddly to connect the throttle cables after the carbs have been installed. Why not connect them beforehand (e.g. like I did in the photo above) and then when installing the carbs remove the throttle grip, and route the cables from the carb through the frame to the handlebar? That at least is my plan or what am I missing?

Someone has offered me a set of VB60A carbs (1979 model year) locally. They seem very complete, obviously they will need to be rebuilt. I probably could get them for under $500. I am aware there are differences to the VB62A carbs which I have on my 80's model. Would it be worth it?

And what is the original diameter fuel line to connect carbs to the tank? There was a 5/16 on my bike which seems too big. Thanks!

[JoeInTUS]

You can install the carbs with the throttle cables installed but the right switch assembly needs to be disconnected and removed from the headlight bucket since either the cable or the switch assembly needs to spin to install the pull cable. I usually do it that way if the switch assembly has not been installed yet.

It can be fiddly with the carbs installed. Sometimes it takes 5 minutes, sometimes a lot longer. If you go that route do it while the engine is still tilted.

I believe 5/16 fuel line is correct for an 80.

[oroepke]

Ok thanks. Switches are off and everything in the headlight is disconnected, because I did a few more things than carbs, so I’ll go that route.
The engine is not tilted, since my bike came with pods. Hopefully I’ll get that valve cover on there properly, there is not a lot of wiggle room. I’ll try the trick with the rubber bands!

[daves79x]

You have likely read the advice about 'sagging' the engine, rather than tilting to get more room for the valve cover removal. As Joe says, if the throttle cables are connected to the grip, you just lay the carbs in place and attach at least the 'pull' cable before popping them into the boots. You do have to remove the small triangle engine brackets, assume you already have.

Sorry, I didn't wade back through the posts, did you ever confirm and post what jetting your carbs have for the pods?

Dave

[oroepke]

Thanks Dave, I was aware of the „sagging“ to get the extra little bit bit of wiggle space.

Yes, here is what I have in there:
Main jets 130
Idle keys #35
I took a picture of the needle, it has 6 clip positions, currently sitting in the 3rd richest, diameter is 2.4mm at the top, 1.35 mm at the bottom, taper starts about 27 mm from top.

At this point I am putting the carbs back on with pods. I just want to see how it runs like this. I was able to source an airbox, but I will also need new oil lines since the after market ones on there won’t clear the airbox. At some point I will put out a post and ask where I can get the correct jets and needles and what else I may need.