New carburetor throttle cable too short?

Hello All,
Bought a reproduction of a 69 K1 late model K29A carburetor. Got it installed and it runs on the upper end of mid throttle?
The valve is oriented correctly so the valve seats to the bottom of the intake horn. Tried to adjust the only adjustment screw visible pictured.
Any insight Would be greatly appreciated.
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20210912_094303.jpg
 
I've run into this issue quite often with the Chinese stuff. Cable ends up have either too much or not enough free play. I have taken a dremel with a cut off wheel and carefully trim away a bit of the housing. Even if you can't get the inner cable out, it still can be done if you're careful.
 
I've run into this issue quite often with the Chinese stuff. Cable ends up have either too much or not enough free play. I have taken a dremel with a cut off wheel and carefully trim away a bit of the housing. Even if you can't get the inner cable out, it still can be done if you're careful.

Thank you very much.

I am assuming by the housing as being the threaded
20210914_180935.jpg
part at the top of the carburetor. I noticed that there's a threaded piece that screws on the top of the carburetor.
Or are you suggesting
20210914_181009.jpg
this piece.


Thanks again for your help.
 
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That threaded piece on the top of the carb is for cable adjustment (like you'd find on a brake lever). When you turn the threads in, you effectively shorten the cable housing giving you more free play. For me, sometimes even that is not enough, and I have to remove the threaded sleeve or actually carefully cut away some of the cable housing (without damaging the actual cable). There have been other times where there is too much free play and I have to machine a spacer to take up the slack ( I have a lathe).
 

scooter

Well-Known Member
Figure out free length of cable that you need by working both ends separately. Get a measurement of cable uninstalled and then get measurements with opposite ends free then remove appropriate amount of cable sheath to your computed value. A sketch of what I mean

image.jpg
 

kirrbby

Well-Known Member
First thing I would do is pull that rubber boot up and onto the cable...out of the way, so you can see where the cable hits the carb. Make sure it's properly seated INTO that adjuster. Then see if it's still revving high.
You also need to be sure that the cable is connected correctly at the other end...throttle end. Does it have the in-bar throttle like the early CT70s?? Or more of a modern throttle?
Is there any cable adjustment that can be done at the throttle end??
 
That threaded piece on the top of the carb is for cable adjustment (like you'd find on a brake lever). When you turn the threads in, you effectively shorten the cable housing giving you more free play. For me, sometimes even that is not enough, and I have to remove the threaded sleeve or actually carefully cut away some of the cable housing (without damaging the actual cable). There have been other times where there is too much free play and I have to machine a spacer to take up the slack ( I have a lathe).
Good information there thank you. i cut about 2/3rds off the threaded end still idling at about 1,500 rpms. will have to work on it this weekend. thanks for your post.
 
Figure out free length of cable that you need by working both ends separately. Get a measurement of cable uninstalled and then get measurements with opposite ends free then remove appropriate amount of cable sheath to your computed value. A sketch of what I mean

View attachment 72079
great diagram!! thanks very helpful. I am having some issues taking off the throttle lever. the bolt heads are striped. so i will have to loosen the handle bars tilt them and inpack driver them off or drill the screws out initially
thanks for the diagram very helpful.
 
First thing I would do is pull that rubber boot up and onto the cable...out of the way, so you can see where the cable hits the carb. Make sure it's properly seated INTO that adjuster. Then see if it's still revving high.
You also need to be sure that the cable is connected correctly at the other end...throttle end. Does it have the in-bar throttle like the early CT70s?? Or more of a modern throttle?
Is there any cable adjustment that can be done at the throttle end??
it was seated in the adjuster cap on the stem coming out of the top of the cap. not sure about the cable end is a barrel end at the throttle lever or not. at the carburetor it is just a lead plug type cylinder parallel with the cable. having some issues with the screws on the throttle lever being striped. will get into it this weekend. thanks for your post and help.
 
Looking at this parts diagram... CT90K1, it looks to have a in-bar throttle..? Similar but different than the CT70?
With the CT70 setup, it's possible to connect the cable wrong to the #14 throttle cable holder part. I'll try to find the pic...

https://www.partzilla.com/catalog/h...with-no-year/ct90k1-a/switches-cables-mirrors

View attachment 72083
very helpful thanks for the pictures gives me a idea of what i am working with. thanks for your post and your help.
 
It's very easy for the cable housing to slide down the cable when your moving the carb in and out. Feels like it's all tight and in place like it should be because the cable slides thru the handlebars which hold it in place, but often not the case and it's slid down. Hold the carb end of the cable in one hand, housing in the other hand. Try sliding the cable housing upward while holding the cable in place.
 

kirrbby

Well-Known Member
It's very easy for the cable housing to slide down the cable when your moving the carb in and out. Feels like it's all tight and in place like it should be because the cable slides thru the handlebars which hold it in place, but often not the case and it's slid down. Hold the carb end of the cable in one hand, housing in the other hand. Try sliding the cable housing upward while holding the cable in place.

Experienced CT NINETY member...Gold nugget advice.
 
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