R67/2 progress

[stagewex]

I had cleaned my carbs last Spring and for the first time couldn't get them to operate correctly. Tried everything and either it was hard to start or when it would it was running choppy. Finally bit the bullet and brought it to the shop. The mechanic had a hard time as well. When checking to see if the jets might be fouled he noticed his gauge-pin went way too far into the jet. Apparently, while they were the correct jet, they had been bored/drilled by a previous owner and I'm guessing for Winter and cold weather riding?
Why he didn't just get the next oversize I don't know.

My bike has always run strong but now with the correct unmodified jets and after over 3 years of ownership it's like riding another bike completely. Super smooth.

So yeah, if you have some good but used gear there's no telling what the history might be?

[Daves79x]

You still need to do the cardboard thing with new points. But the carbs are another thing. If you did not personally completely disassemble them, verify all passages were clean, jets clean and properly sized, and tap out all threads, it's hard to tell what you have. You have to be sure your mixture screws actually seat and seal when fully closed. Often there are bad threads the last couple of turns and you think the tip is seated, but it's not. These are actually very simple carbs, but you can't overlook anything.

The tiny screw you asked about is just a plug from the drilling of the vent hole in the mixture screw.

Dave

[The Plunger]

They(1/24/15-16’s) were sold as completely refurbished and they appeared to be, with all new jets, nuts, screws, caps, gaskets, springs etc., with bright and shiny bodies. Only when I disassembled them did I find the repairs
From this point I’m going to send in my 1/24/25-26 set in to Bing for a new float chamber bottoms and use them as they are otherwise excellent.
Thanks for the tips guys.
Brian

[The Plunger]

Well that makes sense. I’ve found that isn’t the only thing modified on these, holes have been rebored and tapped to larger size and one of the mixture screws is a stepped affair because the port was bored out and tapped. It looks like a Bing made screw that they may sell for repairs. I paid a lot for these carbs to a seller on eBay out of Germany, I’m regretting that decision.
Also discovered I get spark whether key is depressed or not! That can’t be right.

[808Airhead]

I can muggyweld the bowls for you of that is all they need.

[808Airhead]

These bikes are SO sensitive to carburetion. If your carbs are not perfectly functionAL YOU WILL BE CHASING YOUR TAIL. Show us a pic of your carbs and idle screw/mixture setups. Some idle screws are too short and will not even lift the slide up.

[The Plunger]

Thomas,
The idle screws function correctly, I’m thinking it must be the funky mixture screws which I will replace before proceeding. As to the other set of carbs, one has about 1/2 of the float chamber bottom gone so no chance muggy welding that!

[808Airhead]

Yeah,never mind! lol. Can't 'weld' that,lol.

[The Plunger]

After walking away from this POS for the weekend my brother suggested spraying starter fluid in to see if it'd run. Well, hell. So I sprayed some into each carb and she fires right up and runs for 3-4 seconds, repeatedly. So the timing is right, the spark is there, I'm just not getting gas. Tore the carbs down for the 4th time, reassembled, nothing. $1300 spent for carbs that don't work(frowny face here).

[The Plunger]

I got her running again. I put the carbs back together but used different slides and she fired up with a little coaxing and a boost of ether. Then the problems began anew. I got the left side to run alone and mixed right with a nice idle and she'll thump along just fine. The right side refuses to run sans left cylinder and is actually periodically backfiring through the intake and carb! It spouts a cloud out of the cylinder head and carb intake on startup too. I rechecked the valves and it's all good. The question of the day is, why? I'm no carb expert so anyone have an idea? The mixture screw on that side is the wonky re-bored one and does funny things to idle speed in or out. I'm so close, PLEASE HELP ME!!!!

Brian