Topic: 1978 CB750A Exhaust Guide Issues

[LiveeviL81]

Hey All,
I noticed today after cleaning my head that the 4th cylinder's exhaust valve guide is slightly raised compared to the other cylinders. The snap ring is seated slightly in the groove on the guide, but it is not flush with the casting compared to the others. Is this something I need to fix before assembly? Is it as easy as heating the area up and trying to press it further? Appreciate it.

Thanks,
Kaleb

[HondaMan]

I've seen that on MANY of the CB750 engines. It is a 'stop' for the head assembler person, not a 'holding device'. It doesn't hurt anything for it to be a little bit higher or lower than the others unless you're installing a maximum-lift cam of some sort. The valve's position is determined by the cam's lobe (and the rocker arm), so it runs fine that way.

[LiveeviL81]

I've seen that on MANY of the CB750 engines. It is a 'stop' for the head assembler person, not a 'holding device'. It doesn't hurt anything for it to be a little bit higher or lower than the others unless you're installing a maximum-lift cam of some sort. The valve's position is determined by the cam's lobe (and the rocker arm), so it runs fine that way.

Appreciate the info. I was worried it could cause an issue with valve wear, or when determining valve spring height/preload. I wont worry about.

[MRieck]

I've seen that on MANY of the CB750 engines. It is a 'stop' for the head assembler person, not a 'holding device'. It doesn't hurt anything for it to be a little bit higher or lower than the others unless you're installing a maximum-lift cam of some sort. The valve's position is determined by the cam's lobe (and the rocker arm), so it runs fine that way.

Appreciate the info. I was worried it could cause an issue with valve wear, or when determining valve spring height/preload. I wont worry about.

It will affect retainer to seal clearance but if you are using a cam with under .375" lift you're fine.

[LiveeviL81]

I've seen that on MANY of the CB750 engines. It is a 'stop' for the head assembler person, not a 'holding device'. It doesn't hurt anything for it to be a little bit higher or lower than the others unless you're installing a maximum-lift cam of some sort. The valve's position is determined by the cam's lobe (and the rocker arm), so it runs fine that way.

Appreciate the info. I was worried it could cause an issue with valve wear, or when determining valve spring height/preload. I wont worry about.

It will affect retainer to seal clearance but if you are using a cam with under .375" lift you're fine.

Planning on using a 76' K cam, I'll measure the lift to be sure.