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F2 carb issues

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Cb750r:

--- Quote from: K2-K6 on April 02, 2024, 04:27:14 PM ---
Practical advice for OP to check nothing simple is catching you out on this set.

No carbs should "hang" on the throttle pull cable at closed position. This is ONLY facilitated by throttle stop screw next to cylinder #4 in providing absolute slide base position.  If there's any tightness in pull  cable at this position, then it needs adjustment to provide slack such that it can't interfere with complete "drop" onto that stop when you just let the twistgrip go.
Make absolutely sure there's no conflict with secondary cable throughout full twistgrip movement.  There's usually only adjustment on pull, with return being fixed.
You can remove the return cable while you try to diagnose fault, but advise to use when ultimately riding it though.

Idle mixture screws are set from a start point of 1 & 3/4 turns out from fully closed on the F carb set. Anything significant below that will likely give the symptoms described, effectively lean idle, with revs slowly drifting down and stalling. Make sure they are in the starting position if you don't know how they've been set.

Worth verification of these points to see if there's anything basic running you ragged.

--- End quote ---

Really good points, all round. I have a velocity stack/single foam filter setup on my 750 and I have it well sorted jetting wise, and I’m always pleasantly surprised how well it starts idles etc after a long winters nap. I’m a firm believer of a good fuel additive in the winter storage and first several tanks in the spring get a fuel system cleaner as well to help clear up and storage hiccups it’s developed. 

 cable routing can play a big effect on the throttle sticking. Especially if you’ve changed bar type to be different than stock. I have taken a modern bicycle shift cable and unwound it to get individual strands of wire to help gently clean out jets. The individual strands are very fine and are quite good at piercing your skin so you’ll be encouraged to not use too much pressure!

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