Carb Help

[CatatonicBug]

Ah! Are you happy with your dynajet? Now you experienced that kit would you try something different next time?

It gave me several MPG, and a better throttle response. For the later carbs, it's the only way to get new replacement slide needles anyway. If I had it to do all over again, I would still do it. I don't know of anything else to do, besides leave it the way it was.

[New2Me]

Ok I'm seriously getting irritated with this carb business and my Clymer may be making it worse. I tried ordering a carb kit based off what was in the carb and ended up with a 78E kit, but the needle jet dont match the serial on my carbs. Whats on there now is 5GZ6 which is different than the K&L Kit needles from Georgefix. Those are Y265 and I cant tell if they are shaped different or if my eyes are playing with me.

The serial on my carb bodies read 3H3-00 which according to Clymer is for XS1100/SF.

[New2Me]

The E-tubes on carb 1 & 4 have less holes in them them carbs 2 & 3. Is this normal for 78-79' xs1100SF carbs?

[bikerphil]

Ok I'm seriously getting irritated with this carb business

Use the 5GZ6 needles, c-clip in center slot with the least holed emultion tubes in carbs 2&3, that is the way they came from the factory. The further you get from factory tested setup, the more difficult it will be to get them right, BTDT.

[New2Me]

Use the 5GZ6 needles, c-clip in center slot with the least holed emultion tubes in carbs 2&3, that is the way they came from the factory. The further you get from factory tested setup, the more difficult it will be to get them right, BTDT.

That's what I was hoping to hear. What's the point of having different E-tubes? I know they put larger jets in the center cylinders to keep them cooler but wouldn't less holes in the the E-tube just make the engine less responsive?

[bikerphil]

The holes in the emultion tubes are air bleed holes. Less holes= richer mixture=lower cylinder temp. on the two center cylinders.

Edit: The 79SF (3H3) used the different emultion tubes but the same main jets across the board. Later models used all identical emultion tubes but staggered main jet sizes.

[New2Me]

I see well that makes sense thanks.

[motoman]

That's what I was hoping to hear. What's the point of having different E-tubes? I know they put larger jets in the center cylinders to keep them cooler but wouldn't less holes in the the E-tube just make the engine less responsive?

Early carbs were done that way........................later model carbs were two steps difference in the mains. That was for the Standard. The late model Specials were the same size mains across.

[mack]

You never know

what your going to find when you take apart the carbs. I've been cleaning up a couple banks of 78/79 carbs. One was set up for an SF and have the 266/301 emulsion tubes with 42.5 pilots. No issue with them but the other came off an E. It only has the 266's but the mains were all 137.5 accross the four with again 42.5 pilots. The air jets were 210's. This has me stumped as what I expected was 266/301 tubes,137.5 mains, 45 pilots and 185 air jets. Not sure what the PO was trying to accomplish with his set up. Obviously it ran like crap. I know he had just put on a 4-1 exhaust with stock air box, but he never got it to run well. He thought it was a timing issue and played around with that, started the bike and bent all the valves. He ordered and recieved the required parts but gave up on it and bought a new bike instead. Parted out the E and thats how I got the spare motor/ carbs and air box.

[crazy steve]

...but the other came off an E. It only has the 266's but the mains were all 137.5 accross the four with again 42.5 pilots. The air jets were 210's. This has me stumped as what I expected was 266/301 tubes,137.5 mains, 45 pilots and 185 air jets..

Some of the early '78s came with the 45 pilots and 210 air jets, so that's probably a OEM setup....