Reassembled the carbs (twin) on the cbx 250 after a clean.not a total dismantle just bowl, jets and a good blow and clean out. started fine, revs fine up to 7-8 rpm stationary but on the move in 5th gear throttling up from 50-60kph upwards she tends to lose power.more of a feeling of too much fuel than the spluttering of not enough.will eventually gain speed but with a very gradual increase of throttle. What are the likely causes for this!.float level!.blockage somewhere!.jets seem to be clear each time I've looked. Any opinions or help would be greatly appreciate.not that familiar with mechanical terminology so please excuse my not being too savvy.cheers.
mark.52,
Jun 16, 1:56am
The symptoms are more indicative of a too-lean rather than a too rich mixture. If it was so rich that it was losing power, you'd see black smoke out the exhaust.
More likely the accelerator pump (if it has one) hasn't been reconnected properly.
i-n-horz,
Jun 16, 2:17am
She's an 86 cbx.just googled accelerator pump (I'm no A1 mechanic but giving it a go) and I don't seem to recall seeing a lever/linkage type thing that worked with the operation of the throttle apart from the throttle cable linkage itself, I could be wrong.unfortunately my boy is out & about on the bike until tomorrow so I'll give her another look then.cheers mark.52 ;)
mark.52,
Jun 16, 4:22am
I'm not sure if it has one of these (but most engines do.) did you remember to reconnect the vacuum lead!
ceebee2,
Jun 16, 4:33am
Power valve is partly blocked.remove carbs and completely dismantle / clean carb, only way to do it properly.
i-n-horz,
Jun 17, 3:27am
Thanks guys.will be back with results, cheers.
tonyrockyhorror,
Jun 17, 3:47am
Accelerator pump/power valve fault won't cause these symptoms but a hesitation.
If the bike is an unknown quantity, you'd best remove and strip & clean the carburettors, checking and setting float levels etc. as you reassemble.
That doesn't necessarily apply to EVERY carburettor though. I've never set on upside down, but just over vertical so they press lightly on the float needle damper, and the measurement may or may not be to the bottom of the float. Bend the tang on the float to achieve the required measurement.
Don't forget you have to balance the throttle butterflies on multicarb setups too.
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