Thanx for your suggestion. The first thing I tried was my trusty 55-year old offset screwdriver; it had maybe 15 degrees of "swing", not enough to even engage the screw, let alone turn it a bit. Never had BS38's but ran 34's for about 6 years before updating to CVK's. I did synch the 34's on the bike but probably had the tank off the times I did it. Agree that any adjustment should be minor after a good bench synch. In my experience and opinion, it's still worth checking and fine trimming if possible - synching any carbs within an RCH on these 650's is the best single thing you can do to minimize vibration, plus it accounts for any other factors beyond the carbs that may affect strength of vacuum on one side or the other.No need to extend or do anything to the sync screw..........they will be bench sync'd before installing so any adjustment should be miner to say the least, if needed at all..........Buy an offset screwdriver........problem solved............
In fact the BS38's and 34's are just as problematic to adjust once they are on the bike, and any sync work done after the carbs are fitted would involve taking the tank off in most cases..........Non issue in my book
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Yeah, that's the one referenced in post #880, used on 2000-2001 Kaw W650's per the carb fiche for that bike. The fiche doesn't show any other applications, so likely a pretty rare as a salvage item.found that pic with the extension for the idle adjustment
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You'll find that you won't need the "push" cable and can safely trim off its tab if you want to "declutter" - return spring on these carb sets is quite strong.This thread is about a mile long perhaps a fresh thread is in order?
I'd be up for doing a conversion, these are on the shelf, ready to start in on..
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good advice from sci85 who I believe he is the only one of us that has actually fitted and tested the carbs and has them working well .
If the engine is holding back at WOT it should be doing that in every gear not just flat out in 5th
I'm afraid that I am going to have to disagree with skulls advice about jetting .....When changing and testing your main jets one should start too rich and work down NOT UP .
Running your engine at WOT with a rich mixture will not damage your engine whereas running with a lean or weak mixture is a sure way to end up with your pistons seizing at high speed or deceleration and eventually holed pistons .
I'm afraid that I am going to have to disagree with skulls advice about jetting .....When changing and testing your main jets one should start too rich and work down NOT UP .
Its not my opinion its recommended practice to start over-rich and work down to correct jet size on main jets when testing at WOT.can't read posts when you have people on ignore........Agree disagree............common sense tells me when i screw in a mixing screw and listen to any change i will run it past the running good point till it runs rough then turn it out to the best position............
He was just illustrating the basic carb tuning technique of going above and below the ideal adjustment or jetting to "bracket" it and determine just exactly what it should be. One of the first rules of jetting is that when you think you're good, go up another size to see if it runs better or worse, just to verify your previous selection was best.
If a carb set has an established baseline, which this seems to, I don't see the need to start way rich and work down. I'd just pick a size in that baseline, in this case a 138 or 140, and work up one size at a time from there. Any of these baseline sizes are probably close, in the "ball park", so don't skip sizes. Just one size change could make all the difference and totally fix the issue.
He was just illustrating the basic carb tuning technique of going above and below the ideal adjustment or jetting to "bracket" it and determine just exactly what it should be.
I doubt that he needs you to defend him 5T but if that was indeed his intention ....then its a poor analogy as there is absolutely no correlation between setting idle mixture and selecting and testing main jets at WOT ........ Why not simply refer directly to selection and testing of Main jets ?
If a carb set has an established baseline, which this seems to, I don't see the need to start way rich and work down.
Where did I recommend that one should start 'way rich ' in selecting main jets ? i think you read what you want to read sometimes
I'd just pick a size in that baseline, in this case a 138 or 140, and work up one size at a time from there. Any of these baseline sizes are probably close, in the "ball park", so don't skip sizes. Just one size change could make all the difference and totally fix the issue.