How to fix CT70 throttle?

I broke the throttle the first day I got my '71 CT70 and I don't know how to fix it. I've fixed everything else but this whole throttle thing has got me. The grip just spins on the bars without moving the throttle cable. If I grab the grip and pull out on it like i'm trying to slide it off the bars, it moves the throttle cable. How do I fix this? How do I get the grip off? Can someone look at this diagram and tell me what all parts i need to fix it?

http://www.bikebandit.com/houseofmotorcycles/showschematic/m9158sch394667

If I remeber correctly you remove the screw on the underside of the bar, number 26 in the diagram, and the rest comes apart.

I would remove the screw previously stated, it sounds like the cables possibly not broken, something else may have come loose or broke. You wont really know what to order or if you even need to order anything until you take it apart and see what's going on. Take pictures and post if possible, I know there are quite a few people here that are experts on CT 70 series.

The tube (15) has a spiral-cut protrusion on it's inner diameter that mates with the diagonal notch on item 17. As you rotate the throttle in the normal manner, it causes 17 to move towards the end of the handlebar, pulling the throttle cable. A normal spring in the carb slide works to pull it all back as you let off the throttle.

If the throttle is just spinning and spinning, the two aren't engaging. Perhaps that's why, if you just pull the throttle as if you were sliding it off the handlebar, it moves the cable - something else is causing 17 to slide.

I believe the screw (16) fits in that slot at the end of the throttle tube (15) and keeps the tube rotating normally, rather than 'walking' on or off the handlebar. Remove the screw, and the throttle will 'unscrew' off the bar, and you can inspect the whole works.

Quite a few of the late 60s small Hondas used this setup with the throttle cable partially inside the bar.

Lots of places for friction to occur, though. A good cleaning and greasing (17) in the bar, the 15-to-17 interface, and the 15-to-handlebar interface will make a big difference.

Kirk

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