Crepe myrtle has been shown to be a good bow wood, the grain is tight and the fibers hold to themself very well meaning it probably won't lift a splinter. I'm not sure about it taking set or not. I just planed down several trees into boards yesterday here in Taiwan and was impressed with it. My guess is, if the wood is plenty dry, it will do fine with a heat bend assuming you are using a heat gun. I wouldn't use a tourch on it if you aren't certain about its ability to accept the heat....which you aren't. I test bended several thinner branches and you could practically bend them in a circle before they split. Of course they were wet and mostly sap wood, but that is still a good indicator the wood has potential. The heat should take care of any set problems (if there are any), just take it slow and give it time to rehydrate after heating. Does your wood have any heartwood contrast? The trees I felled have a really cool olive heartwood. Be careful storing it as well, it tends to rot easily and bugs LOVE it.
