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Discussion Starter #1
Finally finished carb clean/rebuild and valve adjust. Also new air filter (stock airbox) and iridium plugs. And it runs! Took it all down because it was down one cylinder and evidently fixed that, although carbs were really quite clean when I opened them up.

Now the question; just how important IS it to balance the carbs? I went to great pains to insure:
- Pilot screws were all turned out exactly the same (2 - 5/8)
- Throttle plates were EXACTLY the same opening - checked the plate/carb bore clearance in several places around them with two different gauges of piano wire
- Float levels were as close to identical as possible (they're within a small fraction of a mm
- Vac slide springs were all matching length.

All the valve clearances are also VERY even between all cylinders, and there is just a slight but not unpleasant amount of valve train noise, mostly noticeable just at very low idle.

The initial idle speed was WAY high (about 3k), but that's just because I had the manual idle screw set too high. So after a brief test run (still in garage - no tank or seat) it now starts at just a touch of the starter, will idle smoothly down at 700-800 rpm and seems extremely responsive to throttle blips.

Think I really NEED to balance the carbs?

When we balance them, is it mostly tweaking the pilot screws or the throttle plates or both?

- Jay
 

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Balancing is about the throttle plates, not the pilot screws. (Except very marginal effects.)

If you've got a nice smooth idle, and it picks up & drops back crisply, then I'd say no need to do any further gauge balance. Good going! IME even small movements of the adjusters away from balance produce poor running.
 

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Yeah, Mike's right. If she starts easy and idles smoothly then it looks like you did a bloody good job with your manual balancing method. Job well done I'd say :thumb
 

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Discussion Starter #4
Thanks guys! So I think I'll just run it for a while and not worry about synch right away. Maybe work on making a homemade manometer for later just because I'm a perfectionist.

- Jay
 

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I just removed carbs on my 95 TBird manually set them put them back in then set up the vacuum guages fied her up 2 guages set at 4 the other one was flickering all over the place. I tried adjusting it but wasn't achieving much so killed the motor number 3 guage was done up soo tight it had ruined the O ring in there. I borrowed the guages so I replaced the ring started her up now can't get tge settings right. I don't really want to remove the.carbs again. What's the procedure now. Tge bike starts fine both exhausts.are smoking a little 1 and 3 are at 4 and number two is on 3. Whats the best way to procede I think 1 and 3 are getting two much.fuel.
 

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Is it oil smoke or fuel? lf it is fuel I think you need to remove the carbs and start over. The first thing I would check is your float level. Make sure all carbs are the same, exactly. Also, if it starts easily from cold check the condition of the enrichening circuit valves to insure they are not leaking. Any leak will make that cylinder run rich and cause hard starting when the engine is warmed up. Good luck and let us know what you find.
As an aside, I recently rebuilt the Mikuni carbs on my 2001 Thunderbird and I had to R&R them at least a half dozen times before I got everything just right so unless you got exceedingly lucky or you are very good you WILL have to take them off again.
 
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