Loss of low end torque, 3rd cylinder pooped?

Posted by mluk1 on Aug 27, 2010; 2:28pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/Loss-of-low-end-torque-3rd-cylinder-pooped-tp1372163.html

I finally got my 77' CB750F running good for a couple of months and I even took on the highway on a 3 hour trip twice and everything was fine. My speed was about 140 km/h on average on those trips and I was riding like that for about an hour and half at a time. But the other night I took a friend out of my bike and was doing 100 mph, the ride home was fine but the next morning it my bike felt like it lost a lot of torque. At red lights I started to touch each exhaust head and figured out that the 3rd head was not as hot as the other three.

I don't feel much pull on my bike any more and it takes a really long time to accelerate, it sounds different now too. It has a lower pinch to it and I'm struggling to get up to 120 km/h. Does this mean I'm running on three cylinders?

Could any of these factors have anything to do with it:

- It's freezing in the morning when I take it to work, it's about 10 degrees Celsius
- The oil that I'm running is 15W- 40 topped up with probably about a litre of 10W-40
- The oil pressure light sometimes comes on for a bit but then turns off

Any help would be great, thanks.