HondaCB650

Please refer to the carbs section of my internal technical links list. Most of the answers you look for can be found there easily. Turning out the idle screw to richen the idle mixture is correct. But note that the complete range of the idle screw only covers one or two idle jet size differences so ...

The air cutoff diaphragm is there but there was a small tear along the outside edge, I thought I'd repair it with a bit of epoxy. I'll show a photo of the repair when I return from the head gasket replacement today. Well, there are four of them, only one is accessible without separating the carbs. ...

The camshaft notch is relevant for timing, marks on the sprocket may be nice but they are not crucial for timing. Camshaft timing look all right from your pictures. Note that ignition timing uses the "F" and not the "T" mark. Compared to CV/VA carbs, the piston/PD carbs are quite...

Good idea.
Now someone at the Harley shop lost a bet.

Welcome here! :D ... My other concern is that the engine is running lean because of this. I pulled a plug and it looked a little dry but not too bad. ... CB 650 plugs typically look a bit lean. A bit of white is still all right at least for highway riding. The idle system won't really affect mixture...

What would be the result if I were to go from the stock position with 1.25” mandrel bent steel, and joined 1,3 on the right, starting with factory headers, then having 3 cross over and join 1, then having 2,4 join up on the left with pipe 2 crossing over and dipping under pipe 3, keeping 2,3 separa...

Volker-P I followed the link on your post to a manual. It looks great but I can’t get pop-ups and redirects to stop. Is there an account I need to sign up for to get access? There is no registration or something for the cosky online manual. All you need is a reasonable browser with reasonable setti...

Welcome here! :D I would recommend to read around in the forum a bit to get an idea what you got there. Then read the repair manual as you would read a book to get a bit common with the things in your boxes. Then have a closer look into your boxes and try to recognize the parts you did see in the ma...

Mechanic went back into bike to tighten engine block bolts to stop a leak. If you want to have a tight engine, you have to clean surfaces carefully before reinstall and follow the stepwise torque schemes with a small enough torque bolt. Try tightening bolts at a CB650 head cover or head to stop a l...

Welcome here! :D It should start and run somehow on 3, even on 2 cylinders. Plug cables from left coil go to 1+4 from right coil to 2+3. :wink: Do you have fuel in your floater bowls? You may check by opening the release screws. If your carbs have the vacuum shutoff (a part with several hoses sittin...

Welcome here! :D How do your plugs look like? All four equal? Still the plugs you got with the bike? When you replaced the old carb boots, did you also have a look inside the carbs? First thing for me to try for now would if throttle response gets better when the choke is pulled a bit. I would not t...

Thanks for the helpful pictures. Your plugs look good. 3+4 seem to have fired a bit, too, but never got hot. I would expect 3+4 look wet and black if they had fuel but no ignition or compression. Therefore my guess is a fuel/carb issue here. Forget about the idle jets and passages for now, they shou...

Welcome here! :D Interesting reunion story. To your problems: The plug cables from left coil go to cylinders 1+4, from right coil to 2+3. You would not be the first one who mixes them up :wink: Also try to swap plugs just to be sure. 1+2 are closest to the fuel inlet of the carbs, 3 is a bit further...

Got the pan off and I can turn the starter clutch by hand but it feels really tight. Not good. It should spin free in one direction, only slowed down a bit by the sprockets. Which means there should be a bit of very free play before the starter transmission sprocket teeth really engage. If there is...

Welcome here! :D In fact I never heard of that issue. Remove the starter and have a look into the hole in the crankcase. There should be teeth of a sprocket visible. Usually you can turn the sprocket with a screwdriver to one direction freely, but not to the opposite direction. The mechanical option...