CB77 High Idle

[Seadog]

When I picked up my CB77 a week or so ago, the idle was a bit high at 1000 rpm. After taking it for a long ride a day or so later, the idle increased to 2000 rpm. I attempted to address that today with a tune up using simple instructions found on this forum from Loud Mouse.

I removed the seat, air filters and breather tubes for access to the carbs. In trying to set the slides to the same height, I found that the left carb slide screw had no effect on the slide and the slide would not bottom out. The right side and screw were operating well. I checked to make sure that the carbs were not mounted too tightly. They were not. I thought the throttle cable might need adjustment, but turning the adjustment screw at the top of the left carb all the way down to the cap only helped slightly. I removed both cables and found the left hand slide was operating smoothly and did bottom out, but the adjusting screw is still not as effective in raising and lowering it as the right carb. I guess maybe the carbs need a good cleaning. The left carb slide also looks as if it might have been stuck at some point and someone levered it with a screwdriver. It has a slight nick on the edge.

Are reliable carb rebuilding kits available for the CB carbs?

Even though the carbs might need cleaning, I think the throttle cable is still a problem. I removed the gas tank to see how it was mounted and found that the cable junction was mounted on top of the the frame instead of on top of the right coil, but I cannot see how this would matter, since the two short leads from the cable junction would not reach the carbs if it were mounted elsewhere. The sheaths on the short extensions are only 7 inches long. Wrong cable?

I am going to have to replace the throttle cable anyway because the adjusting sleeve at the throttle is broken. But which one to buy?

I've read here that all CB77s came with a low handle bar, but mine is higher - more like the bars on a CL77. The existing cable sheath is 31-¾" long. Should I be buying the "Mid bar" cable or something longer?

Any thoughts?

[LOUD MOUSE]

Wrong slide. .....................lm

When I picked up my CB77 a week or so ago, the idle was a bit high at 1000 rpm. After taking it for a long ride a day or so later, the idle increased to 2000 rpm. I attempted to address that today with a tune up using simple instructions found on this forum from Loud Mouse.

I removed the seat, air filters and breather tubes for access to the carbs. In trying to set the slides to the same height, I found that the left carb slide screw had no effect on the slide and the slide would not bottom out. The right side and screw were operating well. I checked to make sure that the carbs were not mounted too tightly. They were not. I thought the throttle cable might need adjustment, but turning the adjustment screw at the top of the left carb all the way down to the cap only helped slightly. I removed both cables and found the left hand slide was operating smoothly and did bottom out, but the adjusting screw is still not as effective in raising and lowering it as the right carb. I guess maybe the carbs need a good cleaning. The left carb slide also looks as if it might have been stuck at some point and someone levered it with a screwdriver. It has a slight nick on the edge.

Are reliable carb rebuilding kits available for the CB carbs?

Even though the carbs might need cleaning, I think the throttle cable is still a problem. I removed the gas tank to see how it was mounted and found that the cable junction was mounted on top of the the frame instead of on top of the right coil, but I cannot see how this would matter, since the two short leads from the cable junction would not reach the carbs if it were mounted elsewhere. The sheaths on the short extensions are only 7 inches long. Wrong cable?

I am going to have to replace the throttle cable anyway because the adjusting sleeve at the throttle is broken. But which one to buy?

I've read here that all CB77s came with a low handle bar, but mine is higher - more like the bars on a CL77. The existing cable sheath is 31-¾" long. Should I be buying the "Mid bar" cable or something longer?

Any thoughts?

[Seadog]

Wrong slide. .....................lm

Thanks for that LM. I'll have to look for new slides. But before I give up on these, let me ask this: The bottom of each slide is chamfered - There's a high side and a low side to the bottom of each. Is the high side supposed to be on the engine side of the carb or the outside? They were installed with the high side outward. If I switch them left to right, the low side is outside and they close completely. Could they have been installed on the wrong sides?

The slides are labeled on the bottom. The one installed on the right carb is labled "124" above the needle and below the needle with a symbol that looks like a fat K, then 2∙0 (K2∙0) The one installed on the left carb is labeled PW261 and K2∙0 Does this mean anything to you?

I've read here on the forum that the Keyster carb kits are good for the CB77, so I'll probably go with those. Could you give me some advice about a replacement throttle cable?

EDITED TO ADD:
1. After reading some more, it seems the cutout/chamfer goes outward, toward the air filters. Someone correct me if I'm wrong;
2. I misread the number on the left slide. It's PW26L, not PW261, and;
3. the bottom of the left slide has a wear ring around the pin (see pic). Something else installed wrong?

[Hahnda]

Not all the CB's came with low bars, quite a few came with the mid-bars actually.

These are the mid-rise bars.




These are the low or flat bars.



Slides install chamfer out to filter. You should have a PW26L and a PW26R. Looks like one of your slides could be incorrect. On the other hand it might work just fine. It seems to have the correct chamfer at 2.0 and looks the same. The only thing I can't tell in the picture is if they are mirror images of each other?

I also offer a nice set of carb kits for the CB77.
http://scramblercycle.highwire.com/prod ... kit-qty-2-

[LOUD MOUSE]

The Super Hawk received Mid Height bars at 1024216. .................lm

Not all the CB's came with low bars, quite a few came with the mid-bars actually.

These are the mid-rise bars.




These are the low or flat bars.



Slides install chamfer out to filter. You should have a PW26L and a PW26R. Looks like one of your slides could be incorrect. On the other hand it might work just fine. It seems to have the correct chamfer at 2.0 and looks the same. The only thing I can't tell in the picture is if they are mirror images of each other?

I also offer a nice set of carb kits for the CB77.
http://scramblercycle.highwire.com/prod ... kit-qty-2-

[Seadog]

Not all the CB's came with low bars, quite a few came with the mid-bars actually.

Slides install chamfer out to filter. You should have a PW26L and a PW26R. Looks like one of your slides could be incorrect. On the other hand it might work just fine. It seems to have the correct chamfer at 2.0 and looks the same. The only thing I can't tell in the picture is if they are mirror images of each other?

I also offer a nice set of carb kits for the CB77.
http://scramblercycle.highwire.com/prod ... kit-qty-2-

Thanks for the pics and info Hahnda. I love the look of the low bar, but my old back likes the mid-bar better. I'll order the cable from you. Just to be sure, the mid-bar is the 17910-268-820, correct?

[Steverino]

Thumbs up on the mid bars. I was around back in the day and saw very few low bars. There are more now than back then.
Steve