so I bought some hand grips for my 07 gsf. They don't come with a throttle tube and the grip doesn't fit the factory plastic throttle tube.Meaning..the new throttle grip doesn't have a bell on the inside of the grip that wraps around the throttle tube.  Any ideas on how I can make this work? would be appreciated.

If you mean the inside of the throttle grip is a smooth bore then you can take a file and shave off all the ridges on the stock throttle sleeve.  That's what I had to do to fit my heated grips.

yeah, a little time with an xacto knife and a file is pretty much necessary any time you switch grips, if you're not replacing them with stock. I wish they would stop putting those stupid ridges on the throttle tubes in the first place.

Your other option, if you don't want to modify the original part, is to go online and see if you can find an aftermarket throttle tube, I've seen some for random bikes listed for sale for $1-3, if you can find one that'll fit the GS.

Not quite what I mean Slack. the standard grip is somewhat shaped like a bell. The end of the grip wraps aound the plastic bell.

Make it shaped like a cylinder instead?

If you are saying you dont like the ugly white plastic poking up where the flared end of the grip once was, you have a couple options, Paint the throttle tube black with a rattle can, and ignore it looking kind of weird,

or

do a good job trimming off the flares at the end of the old grips, and install one or both inboard of the new grips.

Thanks for the good advice guys. Much appreciated

The flare helps keep the throttle tube in the correct position on the right hand control.
As I recall (sorry, morning, 33* outside so not ready to tackle the parts pile) the throttle tube is hollow. I do not believe you can trim off the flare without separating the tube from the working end.

FYI: The bumps on the throttle tube keep the grip in place without glue. You don't want your throttle grip slipping.