I have bone grips on my citybike handlebars. One of them is stuck, it has probably been on the bars for 70 years. I can't get a shim under them as they are brittle and likely to break. I'd like to avoid that as they are $60-$80 to replace. I'm hoping to get some warm soapy (Dawn) water in there to use as a lube.

Any recommendations or warnings? I am most worried about staining the bone.

Let your dog loose on it?

I have no idea what a bone grip looks like or how it's attached. If it's a press fit and you can't get under it with lube, I guess heat is your only choice. Hair dryer and some taps with a wooden mallet might do it?

I'd start with attempting to soak it is a pot of really hot water, followed up with compressing the sleeve end. If it gets even a little pliable with the heat treatment but still doesn't budge, you might be able to shove a ~20 ga. needle along the bar, to let some Dawn - liquid along the bar. Good luck!

tried a bicycle pump?

You can't post a thread like this without a pic!

My bad.

Are there any reservations to soaking in the Dawn/water? The bone will absorb the water. Will it dry properly?

I'd guess that the reason it's jammed is due to the corrosion of the h-bar expanding inside the rigid grip. if that's a steel bar (as it appears) then maybe try some mild acid solution if you can get it to wick in around the gap and loosen the rust. I'd try white vinegar before anything stronger...what that will do to bone, I'm not sure. Might bleach it a little...try a test on something like a hambone.

I would figure warm soapy water and a decent amount of twisting should do the job. As mentioned, the grip is probably stuck in place with a bit of corrosion which should give way with a bit of force and then be easy to get the grip off.

Oh, boy. This is a question for a museum conservator, not a bicycle mechanic (and though I've worked as both, I am neither). I would be very careful with any kind of acid; make sure it wont hurt the bone. Soaking in water should be harmless enough, but if it doesn't work-- if you can't get the grip off-- and if there's already corrosion on the metal, the additional water is sure to exacerbate the corrosion problem... not good.

Why do you have to take the grip off?

I'd avoid vinegar. Remember that grade school science demonstration, where you'd soak a chicken bone in vinegar overnight and then tie it into a knot the next morning? That's what vinegar can do to bone.

You know, I have to apologise - I was multitasking, slightly ill, and hereby rescind my former advice. My brain was only one-half on topic, and the bone was in my head, and not in mind. A safer approach would be to try bathing it in warm air, from a hair dryer, playing around the grip to attempt to warm it evenly. So sorry and please forgive my bonehead response!!!

although, I'd think that you might chip the bone.

When I'd put horn/antler knocks on English longbows, I soaked it in hot water, it expanded the horn/antler, and let the glue penetrate better...

Might be worth a try?