Topic: 1966 cb160 revving out of control

[james160]

Hello,
I just finished a rebuild on a cb160. A photo is below for your viewing pleasure. When the carbs are tuned where they need to be and you gently twist the throttle and release it , it revs uncontrollably. It will idle higher and higher up to about 4-5k until you turn the key off until it almost dies and then switch it back on. Then it is fine until you twist the throttle again and it repeats the process. When you tune the carbs elsewhere it doesnt rev like crazy but it backfires through the carbs and exhaust and has no power. I have cleaned the carbs, set the float height, new fuel filters, rebuilt petcock, clean fuel with alittle sea foam in it, new gaskets in the motor and the intakes, old reused air filters, new plugs, old coil, new wiring, fresh oil and a few other little things. I originally thought the spark advancer was extremely loose due to stretched springs...I cut and bent the old springs and it has really good tension right now for spark adcvancement. This didnt seem to fix the problem. Any help would be appreciated.

Thanks
James
[img width= height=]http://i997.photobucket.com/albums/af97/VossHonda/CIMG2567.jpg[/img]

[Rampage1967]

Have you synced the carbs??

[pdxPope]

Flip the handlebars back around and see if it still does it.

You might have a sticking throttle cable. If you are running upside down bars or clubmans or clipons and still using the standard lenght cables, they tend to bind up.


-JP

[james160]

Have you synced the carbs??

Not the slides...I have heard to use an 1/8" drill bit as a gauge but i am alittle unsure where to measure to slide at...

[Old Scrambler]

Yes, your cables may be short and not allowing one of the slides to bottom. Cure that problem first........

EASY Sinc..............Remove AC...........observe the slides in relation to the bottom of the carb venturi.........slowly and gently twist the throttle to see if they begin to lift at the same time.......and when lowered do they seat at the same time?  To get them precise.........place to same-size small drill bits under the slides when at rest and very carefully so as not scratch or nick the slide move them to one side until you can feel pressure on the slide.  Now very slowly twist the throttle while feeling both drill-bits with your other hand.  If one begins to loose tension before the other, adjust the cable at the top of the carb so that booth begin to pull equally.  Personally, I use a thick strand of string or pieces of paperboard instead of the drill bits.

[james160]

Thanks for everyones help! The problem was i am an idiot! I synced the carbs...still did it, static set the timing...still did it, then i realized my throttle adjustment at the throttle wasnt allowing the slides to close all of the way!! IDIOT!! Backed the adjustment down and now she runs like a dream!! thanks for all of your help guys!

[Tim.]

   Gotta love a nice running bike.  Looks great too.