HondaCB650

Welcome here!

Hm, this looks like fuel line dimensions and no stock clamp.
From the bottom of the carbs means it is connected there (to what?) or just ends there above the transmission case?

I'm going to run the bike as is for a long ride and see what happens. Maybe go another ⅛ a turn out. Good idea. In the times I was riding my CB over winter the engine required an extended ride at changing revs and loads in spring to run really fine again. :wink: Popping issue might be missing exhau...

..., I will have all of the plug welds on the frame completely welded. The removable frame leg will stay removable though which will be a very big weak point. When I say weak frame I think of tube diameters and connection geometry. Tubes and welds usually do not crack so steel and welding work seem...

Welcome here! :D You did a very interesting project there! This really does not look like a 1970/80's bike any more. Swingarm maybe a bit long, but everything else looks like it could be a Honda design, too. Often it is tough work to make things look fitting unspectacular together so I'd say this is...

Nice 550 Project, just lots of dust but fine basis.
Guess there is no issue happening when riding at load at at 4000K that can be solved just by pilot screws. Except maybe to finally install them because they were missing.

Yes, start with the look at the spark plugs. Typically for stock they look a little bit white as setting is already on the lean side. K&N without oil might be too lean then, but CV carbs are not that sensitive to the air side as the PDs. Moreover all four plugs should look equal. Sounds a bit li...

These are really pretty parts.
They appear significantly older than our bikes to me. Possibly a rarity?

Welcome back! :D good to hear things go better for you now and you find time for your CB again. Be aware that a defective VRR can kill the rotor or vice versa. Multiple failure of charging parts is a hint that probably something else but the failed part is wrong. Possibly something tricky that only ...

A CB650 could make 55mph on two cylinders. So something is really wrong here. As you should have the CV carbs, I doubt that it is the missing air filter seal alone but it should provide already a step to the right direction. For the air filter seal I found that one or two rubber rings from preserves...

So far things sound unsuspicious to me. Do you have any issues like backfire, hesitations at the throttle or something like that? Or does it run more or less fine and smooth but just lacks top end power? What is your current topspeed and what is your mpg? Do you live at somewhat higher altitude abov...

First check out if all four header pipes get equally hot. Plug cables from left coil go to cylinders 1+4, from right coil to 2+3. :wink: 50mph at 4000rpm at 5th gear sounds reasonable. The CB650 lives from revs rather than torque. Also full oil pressure is available only from above ~3000rpm on, so a...

Guess "a little bit" got lost, probably this one was meant: :wink: https://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-electronic-lighting-parts-mini-aluminum-rectangle-chrome-amber-turn-signals-blinkers-25-8301cm.html Well at least you cannot ...

It is not really recommended to run without an air filter. Moreover as K&N are typically reported to be less restrictive than stock air filters be not too surprised if it is the same again or even worse with the paper filter you just ordered. In this case check your choke flaps position and main...

Thanks for the Feedback. :) 1981CB650C should have the VB/CV carbs so it is interesting to hear that K&N make the bike cut off even below 5000rpm. Do I understand correctly that it runs fine without any air filter? Or do you run the stock air filter now? BTW, it would have been more useful to ju...

Sorry, no idea or quick find on resistance values but possibly this Ignition coil test? link already helps a bit.