Honda CB250N Super Dream Carburettor Refurbishment

[@PeterHall-qt8er]

Hi, trying to reburb a pair of carbs for my CB400 Superdream after float chamber overflow. On investigation the float needle valve (the one with a bit of wire on top) has a piece in the middle that can be depressed against spring pressure. So that would explain why the fuel bypasses the valve seat and floods....but why does the valve needle have a sprung plunger in the middle! Any ideas? Many Thanks

[@colindowd3892]

Afternoon Proffessori, Nice job, takes me back to my youth. A Saturday job working in a bike shop owned by a friends dad. Good old Amal cards.

[@chadthomas1666]

Thanks for your help mate

[@leslietait9028]

Can I ask what size tank capacity you used to clean the carbs in and the make of the ultrasonic cleaner

[@SongsFromTheSaddle]

Check out my earlier video about using the ultrasonic cleaner. I give all these details there

[@mikewalker1885]

Wish you'd have shown how to refit them, I'm fighting with that job now aaaaaarrrrggghh

[@SongsFromTheSaddle]

I didn't remove or refit them. I just refurbished them.

[@manosparavida3551]

If the engine's in situ' they're a b'stard to install. You'll have to loosen the rear mudguard, airbox and shift it (the airbox) back an inch or so. But even then it's a nuisance to fit. I left my intakes on the barrels and tilted the carbs @ 45-50° after oiling the inside of the intakes. My engine's currently on the w-bench, so I'll eliminate that bind.🤞👍

[@mikewalker1885]

Did it by cutting the rear off the rubbers, the bit that goes into the air box.

[@frankenbikestien5073]

i've seen worse video's points to note...only use JIS tipped screwdrivers, Phillips screwdrivers will mangle the screw heads, flat head screwdrivers should fill the slot for the length of the slot, an undersize screwdriver will mangle the slot, ....only use six point sockets on the jet tube......never use twelve point socket or ring spanner,.... only use a decent cleaning solution in the ultrasonic cleaner......the pilot airscrews have a washer between the spring and the 'O' ring, chances are, the old ones are still stuck in the jet tube. clean the float valve seat with metal polish and cotton buds.....look for a bright shiny ring.......do a bench soak test with an auxiliary tank with a high head to check valves for sealing.... and lastly, just hope that some idiot in the past hasn't 'rebuilt' them using a pattern kit and blindly changed needles, airscrews and jet tubes...items in pattern kits do vary from OE and could cause problems and should always be compared with known 'OE' if they need to be changed

[@SongsFromTheSaddle]

Thanks. All great tips.