Motorcycle Repair: timing mark on Honda 450 Nighthawk, honda 450 nighthawk, fuel air mixture

Question
Hi Mark,
I'm getting ready to adjust the valves and cam chain on my '82 CB450SC NightHawk. I just bought the bike 3 months ago and it has developed a rattle above idle speed that I percieve to be valves or cam chain. I have the specs for the tappet clearance, but I'm not sure what side case I have to take off to see the timing mark.  Could you explain the location and what I should be looking at.  My Moto Guzzi is quite different to adj. valves then the Honda.

Also, my CB400T Hawk has a small nut on the back of the jugs, in the low center position to adj the cam chain, is it the same on the 450SC?

Thanks       guzziguy88@hotmail.com  

Answer
Hi Terry,

The right side case. Remove the (tappet) cover at about the 1 o'clock position.

Some helpful reading I found on line is below.

Respectfully,
Mark Shively



Making adjustments on Cam Chain Tensioner and Acceleration Pump

I found a substantial improvement in the sound of the top end of the motor after taking two minutes to loosen up (then retighten) the self adjusting cam chain tensioner and let it do its thing. Before this adjustment I was getting a rattling/loose sound from the top end at about ~4300 rpm. The sound is now totally gone. I have also pulled the carbs and found the acceleration pump was mal-adjusted and was not doing its job at all. After the fix (parts available on eBay for less than $20), I now see four nice little spurts of fuel down through each of the four carbs whenever the throttle is whipped open (the design here is to keep the fuel/air mixture from becoming momentarily too lean when the throttle plate is suddenly opened). With this repair, I hope to see an even better throttle response now when I get it back together.

Maintenance Tip sent to me from Paul Devlin, Ottawa, Canada