dmp (01/10/83)
Subject: Re: Honda CB750C transmission problems It was suggested that others might like some information about a particular problem common to many Hondas, especially 750s, and maybe other bikes. Following is the information sent to the original information-queryer... ----------------------------------------------------------- Lucky sir, you are one among many ( + MANY + ), that have problems with a 750s transmission. I own a 1975 CB750 and have had the same problem and have had to deal with it in an extreme manner. This is the problem with your 750 (and other 750s and other HONDAs): The type of transmission that Hondas have cause this to happen either because a lack of precision in the machining of the gears, or overall poorly designed gear machanisms. What happens is that two gears next to each other on the same shaft are pushed together and interlock via dogs, (pegs that stick out to its side), which go into holes on the other gear. One of the two gears is spinning, and when it is pushed into the other gear, it creates a new drive configuration, (ie. gears 1 - 5). The reason the it is hard to shift, rough or makes noise is that the Honda trasmission mechanism is not designed well enough and the dogs on one gear have a hard time getting in the holes on the other gear. The reason that it pops out of gear into what is called 'false neutral' is that the dogs get worn and rounded and do not stay in the opposite gears holes well enough. The more the gear slips out into false neutral the worse is gets. I personally have pulled my engine right out of the bike twice to fix the transmission by replacing worn gears. It works fine now. Still noisy and rough though. Along the same lines, there is the shift fork that pushes the gears together which also wears, which then makes it more difficult to get the gears together, and therefore they slip out into false neutral often. I will be glad to talk to you, or give you a more detailed description of what happens, the causes, effects and cures. Beleive me, I could have used the help when I had the problems. I could supply you with diagrams or whatever you may need. Glad to help a fellow cycler... Dave Plaisted ABI Holmdel, NJ ariel!dmp (201) 834-3080 Good Luck!