Ok so I have begun my engine rebuild, which I mainly think is only going to consist of re-ringing the motor. I believe that all of the bearings and such will be fine. So instead of just pulling the engine I am reworking components as I need to remove them. First I removed the carb rack so I could replace all the buttons with the black delron as I have in other mods that I have shared on the forum. I also removed all the lettering from the caps so they look super badass now, Ill post some picks later.
Next I began to remove the heads so I could take them all apart, clean the valves, and machine or lap them as necessary. So far the lapping is working just fine. Now, here comes the question, upon inspecting the cam lobes for wear I discovered something that you may or may not be aware of. In the Clymer manual, which is what I have, it shows that the specs for both the intake lobes and the exhaust lobes are the same for years 75-77 and different for years 78-79. However when I check the Honda manual via the forum it shows that they are different and gives no discrepancy between model years.
Here is what my cams measure:
Intake 1.460 on all 4 lobes. The book shows a size range of 1.459-1.465 with a service limit of 1.448 so all good there...
Exhaust is 1.440 on all 4 lobes. This is where I get confused a little bit. Here is why....
The Clymer manual shows a size of 1.459-1.465 with a service limit of 1.448 for years 75-77 and sizes of 1.445-1.451 with a service limit of 1.437 for years 78-79. So when I measured my exhaust lobes I'm sayin to myself "man those lobes are nearly .020 below factory and .008 below the service limit". Then I went to the forum and checked the Honda manual which shows sizes of 1.445-1.451 with a service limit of 1.437 with no difference between model years.
The bottom line is I believe, according to the Honda manual, that my cams are indeed just fine. So, does anyone have sizes on thier cams that I can compare to? Is this hickup in the Clymer manual well documented like the jet mixup they have published?
It seems as though I should really ditch this Clymer manual and invest in a Honda manual. I'm just looking for some affirmation that my cams are indeed fine and are actually within spec.
Next I began to remove the heads so I could take them all apart, clean the valves, and machine or lap them as necessary. So far the lapping is working just fine. Now, here comes the question, upon inspecting the cam lobes for wear I discovered something that you may or may not be aware of. In the Clymer manual, which is what I have, it shows that the specs for both the intake lobes and the exhaust lobes are the same for years 75-77 and different for years 78-79. However when I check the Honda manual via the forum it shows that they are different and gives no discrepancy between model years.
Here is what my cams measure:
Intake 1.460 on all 4 lobes. The book shows a size range of 1.459-1.465 with a service limit of 1.448 so all good there...
Exhaust is 1.440 on all 4 lobes. This is where I get confused a little bit. Here is why....
The Clymer manual shows a size of 1.459-1.465 with a service limit of 1.448 for years 75-77 and sizes of 1.445-1.451 with a service limit of 1.437 for years 78-79. So when I measured my exhaust lobes I'm sayin to myself "man those lobes are nearly .020 below factory and .008 below the service limit". Then I went to the forum and checked the Honda manual which shows sizes of 1.445-1.451 with a service limit of 1.437 with no difference between model years.
The bottom line is I believe, according to the Honda manual, that my cams are indeed just fine. So, does anyone have sizes on thier cams that I can compare to? Is this hickup in the Clymer manual well documented like the jet mixup they have published?
It seems as though I should really ditch this Clymer manual and invest in a Honda manual. I'm just looking for some affirmation that my cams are indeed fine and are actually within spec.