WaddleDee72
CB750 Member
I'm at the end of my rope with this bike.... I've been chasing this problem for a year, and in that time I've spent countless hours reading through forum posts, replacing parts, and taking it to different mechanics, all to no avail.
Here's the issue: My bike starts up and runs fine, but on a longer ride (45 minutes or more), it will seem like it's running out of gas. It will sound like one or two cylinders drop out, and if I keep pushing it for a minute or two, the engine dies completely. If I pull over and wait for 10-15 minutes, it will start up again (roughly), and I will be able to go another mile or two before it dies again.
It's more likely to act up under higher loads. If I'm cruising around at 40 mph on surface streets, it's usually fine. But if I'm on the freeway going up a hill in 5th gear at 5k+ RPM, that's usually when it gives up on me. Another point: if I give it full throttle when the cylinders start to cut out, they come back to life and the bike runs perfectly (for a bit before it dies). <That makes me think it's a carburetor issue, but my Honda mechanic is adamant that's it's a problem with the ignition.
The previous owner installed a Dyna S electronic ignition, and I've replaced both coils, thinking that would help, but it made no difference.
Any ideas from the CB750 owners' knowledge base?
Here's the issue: My bike starts up and runs fine, but on a longer ride (45 minutes or more), it will seem like it's running out of gas. It will sound like one or two cylinders drop out, and if I keep pushing it for a minute or two, the engine dies completely. If I pull over and wait for 10-15 minutes, it will start up again (roughly), and I will be able to go another mile or two before it dies again.
It's more likely to act up under higher loads. If I'm cruising around at 40 mph on surface streets, it's usually fine. But if I'm on the freeway going up a hill in 5th gear at 5k+ RPM, that's usually when it gives up on me. Another point: if I give it full throttle when the cylinders start to cut out, they come back to life and the bike runs perfectly (for a bit before it dies). <That makes me think it's a carburetor issue, but my Honda mechanic is adamant that's it's a problem with the ignition.
The previous owner installed a Dyna S electronic ignition, and I've replaced both coils, thinking that would help, but it made no difference.
Any ideas from the CB750 owners' knowledge base?