Frequently Overlooked 750 SOHC Maintenance Areas
Mike Nixon

Honda's venerable SOHC 750 is getting a lot of attention these days. It's no secret that this machine requires a bit more maintenance than do most newer bikes. Following are a few areas that you want to be sure and not miss while you're doing the spring get-ready maintenance. For the full story, scroll down to the bottom of the page and check out the booklet offer. :-)

Everyone complains that the valve inspection caps are difficult to remove without tearing them up. They can be, for sure. But that's not Honda's fault.

About every third or fourth tune-up, you need to replace the inspection cap o-rings. Notice how flat looking this one is. That is what is making the cap stick so hard to the cam cover that it doesn't want to come off.

Get that o-ring off of there and replace it. You will be surprised at the difference it makes.

Here's an often overlooked item. Even a 750 spotlighted in a magazine recently had this issue. Note this axle clamp. It shows a gap on both sides of the axle. This is not correct, per Honda.

Here's the clamp removed. Notice there is an "F" marked on it. One end of the cap is oriented toward the front of the motorcycle.

Here's why. Here the clamp is butted up to the front brake disc, for illustrative purposes. See the difference in thickness of each end of the clamp? A pretty big difference.

Once the clamp is properly installed, it then must be tightened correctly. Tighten the front nut first, then the rear. The end result should be as shown here, the gap is gone at the front, but plenty of gap shows at the back. This is factory.

Honda used only two brands of ignition points on all the early SOHC fours, TEC and ND. Shown here are four different brands, only one of which is stock Honda. Note the difference in construction. The fact is, non-original points are harder to time and dwell in correctly. Your choice. I have a booklet that goes into the differene between stock and aftermarket points in more detail. Check it out.

Don't forget, if you have individual air filters like these K&Ns, they must be removed and cleaned, then re-oiled. The K&Ns in particular, no matter what they say, must be cleaned regularly.

When doing the yearly full maintenance, don't overlook any oil leaks that the bike may have developed. This tach drive seal was leaking, a common issue with this model. It is easily removed and replaced.

Another common oil leak area is the shift shaft seal. It also is very easy to replace. You don't even need to drain any oil out. Use a piece of pipe to install the new seal.

Finally, notice this picture of one of the spark plug wires. You will see that the stock plug wire is metallic, not the fibreglas stuff the car world uses. You don't need to replace the factory spark plug wire (or coils) unless the wires get so brittle they start cracking, or they come loose from the coils. The factory's stainless steel plug wires are otherwise lifetime.

A more thorough treatment of this job of completely servicing the SOHC 750 is outlined step by step in my booklet, Tuning-Up the Honda SOHC Four. Included in the booklet are over 150 illustrations showing how to adjust the valve clearances, cam chain tension, as well as how to properly service the clutch, controls, drive chain and battery. This 47-page booklet is just $27.95, plus $5.75 for continental domestic shipping. Use PayPal or contact me for more information.