CB160 - Timing Question

[acurtiss]

Hi all,

I picked up a cb160 last week and spent the weekend trying to get it running. (I also have a Superhawk, but I hope it's ok to post a cb160 question here! The concepts should apply to both.) I went through everything I could, starting with checking the valves, cleaning up the carbs to make sure fuel was getting through, etc. My problem is with the timing settings. I'm going off of the factory service manual and a couple of other resources, and all say to set the points statically so that when the timing indicator is at F, the points "just open". I'm confused about this because that depends on which direction you're turning the crank. I assumed it meant in the normal direction of operation, but that seems to leave the timing 90 degrees off when I checked with a timing light, cranking with the starter. Any thoughts? Am I missing something obvious?

As it is, the bike has yet to show any signs of life so I'm looking for any ideas out there for what I might do next. (I tried checking the compression already but my tester won't make a seal - that said, it seems like there is a good amount of compression based on how it feels turning it over by hand.)

Thanks,
Aaron

[LOUD MOUSE]

As you points are on the left side (CB/CL72/77 is right side) your rotor will turn to the left (counter clockwise) and you will time the left side first. ...............emo

Hi all,

I picked up a cb160 last week and spent the weekend trying to get it running. (I also have a Superhawk, but I hope it's ok to post a cb160 question here! The concepts should apply to both.) I went through everything I could, starting with checking the valves, cleaning up the carbs to make sure fuel was getting through, etc. My problem is with the timing settings. I'm going off of the factory service manual and a couple of other resources, and all say to set the points statically so that when the timing indicator is at F, the points "just open". I'm confused about this because that depends on which direction you're turning the crank. I assumed it meant in the normal direction of operation, but that seems to leave the timing 90 degrees off when I checked with a timing light, cranking with the starter. Any thoughts? Am I missing something obvious?

As it is, the bike has yet to show any signs of life so I'm looking for any ideas out there for what I might do next. (I tried checking the compression already but my tester won't make a seal - that said, it seems like there is a good amount of compression based on how it feels turning it over by hand.)

Thanks,
Aaron

[swampyankee]

If your 160 motor is like my CD175 - which I believe it is since they take the same gasket kit - the motor is connected to the trans via primary gears, not a chain. Which means the motor itself rotates *backwards*.

If you've been rotating the motor by the bolt on the end of the stator and you've been turning it forward like you would with your 305 to establish your static timing, that could be a problem.

Of course, I'm no emo, so maybe someone else can chime in to confirm or deny this.

Neil

[LOUD MOUSE]

Think about this.
How many of the engines on the 5 bikes ya list have a crank that rotates to the rear and not the front. ................lm

If your 160 motor is like my CD175 - which I believe it is since they take the same gasket kit - the motor is connected to the trans via primary gears, not a chain. Which means the motor itself rotates *backwards*.

If you've been rotating the motor by the bolt on the end of the stator and you've been turning it forward like you would with your 305 to establish your static timing, that could be a problem.

Of course, I'm no emo, so maybe someone else can chime in to confirm or deny this.

Neil

[swampyankee]

Ummm...none at the moment, although the Beemer rotates to the right. :) I've sold the CD175, but it did, in fact rotate "backwards".

But I'm not sure I understand the point of your question.

[LOUD MOUSE]

If that engine rotated to the rear tis the first I've heard of.
Any reason ya think it rotated to the rear rather than the front?. ................lm

Ummm...none at the moment, although the Beemer rotates to the right. :) I've sold the CD175, but it did, in fact rotate "backwards".

But I'm not sure I understand the point of your question.

[swampyankee]

It had a gear primary instead of a chain, which meant the crank had to rotate backwards to mesh and drive the clutch and input shaft the "correct" way. Otherwise I'd have 4 reverse gears. :)
I discovered it when I had it apart to replace the pistons and went to reassemble the head, etc. Also, the cam chain adjuster was on the front of the motor - another tell-tale sign, since the "slack" side of a forward-rotating motor is on the backside of the chain. I'd assume a 160 is the same since the racers routinely use the sloper 175 heads and jugs on the 160 bottom end.