Yet another carb thread!

[XSLeo]

Your float level sounds good.Your needle clip position sounds to rich. It should be in the 4th slot from the top for stock. Just to check are you sure they are 75 carbs? I don't think they put the place to hook in barbs in the carb bodies until they linked them in 76. The 75 had two seperate carbs, two throttle cables. One link was the enrichener, it was in the left carb and linked to the right with a hose.
There was a link between the fuel inlets too, a hose.

 

[5twins]

Your float level is indeed correct. 24mm +/-1mm is the spec for the '74-'75 carb set and you have measured from the correct spot (bowl gasket surface). The different setting specs you're seeing are probably for different year carb sets. The spec varied depending on the carb set.

 

[Nine_Iron]

Just thought you guys that were following this and helping would like to know.......I was drawing air in after the carbs!

I pulled the carb mounts to install my zerk fittings to sync them and noticed a ton of cracks in the material. So I put it all back together and sprayed starter fluid around the area (which I've done before but with very little starter fluid and no change in rpm) and this time my rpm's revved a bunch.

So thanks again for the help guys. Case closed!

 

[rbjenterprises]

scratch this Early BS38s

Have you ever drilled an early 1975 carb to create the holes for the zerk fittings? I think I have the cast bosses in my carbs just no plugs.

 

[XSLeo]

On the early two cable carbs you can use the dead cylinder method to sync the carbs.
It's detailed in the repair manual. Just with the Pamco don't just unplug one plug wire. You need to hook a plug in the wire and hold it to ground as you do the carb sync.
I built a set of adapters that screw on the plugs and then the plug wire hooks to the adapter. The adapter is long enough so there is about 1/2 inch of bare metal showing. I then use a jumper wire to ground one plug to "dead" that cylinder.
A spoke nipple and a inch or so of spoke works as the adapter.
I had no nipples or spokes so built a threaded tube out of some scrap metal and the right size nail threaded to match.
Up in the TECH section, under homemade tools, you might find a pic of the adapters.
Leo

 

[650Dave]

Back to tools used to sync the carbs. One way to dampen the pulses that a single cynlinder causes with a vacuum gauge is to insert a carburetor-type fuel filter in line between the carb and the guage. Smooths out the needle very well. True, a manometer is probably more accurate, and I use one to sync the throttle bodies on my old Vette, but it is very sensitive and a bit tricky to use, especially on a carb that is feeding only one cylinder. Dave

 

[rbjenterprises]

I just picked up a Harmonizer Vacuum Multi-Tool, hence the need for vacuum barbs on my 75.

http://www.advrider.com/forums/showthread.php?t=701625

I wouldn't have a problem drilling the head for nipples but I don't need to take it off for any reason. My BS38 carbs do not have the plugs for the vacuum ports however they do have the cast bosses. I am just trying to see if anybody has drilled them out and inserted nipples and/or plugs. I don't mind being a guinea pig but I figure I would ask and see if anybody has done it already.