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Ok, so I had all the cables redone, which Flanders duplicated what was on the bike. I can't figure out the throttle cable. First thing is it's not spring returning back to "idle"; secondly I don't see how the cable attaches. Here are some pics if you can shed light on this for me:





My manuals are with ECS with the engine so I can't look the information up.

So I think I figured out the problem, I pulled the old rusty throttle off the bike and it is completely different.



So, how does the cable attach to the cleaner version on the bike? Or, does anyone know where to get a NOS of the original?

Hi,

Lift the little brass nut, this is a cable stop with a screw so you can slide the bare cable (thin cable stop goes to the carb) if you have two small cable stop, check measurement first then cut the cable using a dremel disk or a cable cutter, then slide the bare cable in the brass cable stopper, adjust the length then tighten the screw.

I don't recognise the twistgrip in the 2nd post, but the first shows the type I'm familiar with on Ducati singles.
The system uses a solderless nipple, that we can see resting in place at the end of the chain. It can be lifted out.
To use the cable you have, you'd need to cut off any nipple already on the inner cable end. Then install the brass solderless nipple to the cable inner.
It's nice in that you can adjust the nipple's position before final tightening, removing the excess inner cable length when done.
For more reliability, you could replace the solderless nipple with a soldered type, but the standard arrangement gives few problems.
These twistgrips suit a carburettor to 30mm, and are nice and compact. The chain spares the cable from having to bend around the throttle drum.

Jordan

The second set of pics is a throttle from the 2-stoke Ducati's. Or, at least that is what is on mine. You can find the small brass nipples with set screws on eBay and I think Joe Carter eurotrashjambalya has them also.
Tony

The spring that returns the throttle to idle is the spring inside the carb located between the cap and the slide; that is to say unscrewing the carb cap reveals a large spring whose OD is just under the ID of the carb sleeve. It's not a particularly strong spring because you always have to open and hold the throttle open against its resistance.

For that reason it is critical the throttle cable inside the sheath should slide freely and the twist grip should have as small an amount of friction as is attainable. It's easy to check the the twist grip and cable by simply disconnecting the cable at the carb end and twisting the throttle.

Lastly you will want to make sure that as you complete the throttle cable installation by connecting to the carb slide that the slide is resting near the bottom of its travel at idle position when the twist grip is in the throttle closed position. For final adjustment you will be taking out the slack in the cable so you won't have to twist a whole bunch to get to the point of lifting up the slide, but not at the expense of lifting the slide up while the grip is closed because that would take the carb off the idle circuit.


Jim