Difference between SOHC and DOHC

[Iceman16]

Hello everyone,

Rebuilding a 1981 Honda CB750 engine. I’m thinking about buying Mark Paris My Cb750 book. But, it’s meant for SOHC engines. My assumption is there’s almost not a ton of difference with design and that I could use Mark Paris book for my 81?

Let me know why you guys think.

 

[madmtnmotors]

I would argue that there is indeed a ton of differences. Mark's book is very good and I have a copy for my stable of SOHC's, but is also very specific to the SOHC. The DOHC engines use shims for valve adjustment, came stock with electronic ignitions, ignition and alternator are on opposite sides on the DOHC vs SOHC, the DOHC uses solid state voltage reg/rect, different style carbs, plus many other differences that I believe would make it difficult to apply Mark's book to the DOHC.

 

[Biebs]

I think the reading of Mark's book would give you a good idea on engine rebuilding. If you like Mark's style of writing.
Your not reading reading a novel from cover to cover to get some kind of story.
Reference guide to the species of your engine, year, make, model.

SOHC and DOHC engines are the same kinda with differences and upgrades / changes from year to year.


Having a 1992 CB750 DOHC (Nighthawk) I am required to do valve adjustment NEVER!!! WOW!!
But it is important to have clean engine oil to keep the hydraulic lifers clean.


So you are not reading a novel/ story with a happy ending - tech manuals are a reference guide you will jump from chapter to chapter - not in order and will be using the index.

 

[Iceman16]

Copy that. Good to know.

Thank you for your responses. It seems as though the book may help gain a knowledge of the engine but it’s not apples to apples. I probably won’t buy it and will just work with my manual.

 

[mrtwowheel]

I get confused enough working on two different bikes at the same time.

 

[SenseAmidMadness]

Definitely buy the correct manual for a DOHC. The SOHC is so very different. Hell, it's dry-sump lubrication with a separate oil tank and the DOHC isn't. Even something as simple as an oil change isn't the same.

 

[dirtdigger]

There are literally no parts the same between the two. They are completely different engines and bikes.

 

[alex961]

SOHC - Single Over Head Camshaft
DOHC - Double Over Head Camshaft

So, there are significant diferences in the machine type.