1973 Z1 owner from North Carolina

Hi, I'm new to the forum but not new to motorcycling or Z1. I have a few bikes including 1975 BMW R75 and a 2008 Harley Springer. I look forward to contributing and maybe getting some help on an ongoing problem with the Z1. Although the problem relates to extremely rich running I believe I have eliminated the Carbs. Let me know what technical forum I should go to and  open up a dialog. It looks like there are some knowledgable folks out there so thanks in advance.

Welcome to KZRider 
 Lots of great help from our membership
Nice Bike 
Dave

Welcome from the UK

Welcome to KZRider.

Yes, welcome!  Have you rebuilt your choke plungers?

Choke plungers would be guess also. I normally replace them when I work on a set. 

Welcome to The aZylum, our little interwebs corner of motorcycle madness.

Good Ridin'
slmjim & Z1BEBE

Thanks for the suggestions. 
After playing around with the carbs for months I sent the set to a specialist. He inspected and concluded that they were set very close to perfect. The final test was a road test on his test bike (lots of tests in that sentence) all ok. Compression 120 on all pots.
Timing  (cam and Ignition) as close to spot om as I can get it. New coils and "wired George" modification to ensure solid 12V+ at the coils. Spark checked with a tester and jumps a gap to indicate better than 20KV.
All 4 plugs soot up very badly within 2 minutes running. It sounds great until then.  I just know its going to be something stupid that I have overlooked. If anyone knows of a "great" mechanic in or around the Carolinas I would be interested. 

Nice looking Z! Food for thought. Quick question though, is the engine out NOW or is the pic of completeness a re-install? I have some info on the carbs if it helps the "rich" condition. Pertaining "only to the carbs" though, i do a lot of the ramp style 72-75 Z's. Are You close to Asheville, NC?   

Hi,
I am in Wilmington NC so its quite a way from the mountains. The bike is all together and I don't know how the pic of the engine got attached although I probably selected it by mistake. I would like the info on the carbs .... you just never know if you are missing a piece of the puzzle. The fact that all the plugs foul at the same rate and so quickly leads me to think I'm missing something obvious. Particularly since they worked fine as a set on another Z1. I don't think its a fine tuning issue but likely to be a component failure or I have hooked up something wrongly. There cannot be too many issues that affect every cylinder in exactly the same manner. It seems I am going round and round in circles on this one and its not as if I am inexperienced. Iv'e been working on my own stuff for over 50 years and never been stumped like this. I will (for the 100th. time) remove the carbs and clean and inspect the choke plungers etc. as some of the members have suggested. I' m leaving on a 10 day trip shortly so may not have a chance to do much till I get back. Thanks for your input, I really appreciate the willingness to help.

Did your carb guy tell you what the internal parts sizes are. Telling you the are close to spot on is subject to the carb guy looking up the correct carb rack to compare yours to. Before any information can be given the forum will need to know the current setup. 

Things to consider. Saturated pleated air filter if installed, plugged vent tees (those little whitish barbs fittings (2) for starters. By fouling do You mean the "look" sooty or does the Z quit running? Did you clean the plugs to their original color for comparison between tests?