My pine does not turn yellow tip when i bend them, in fact pine is one of the most flexible to bend among the tree that i have enconuter.
By there is two pines i left in my brother house, one not expose to full tropical sun that is from 8am to 1pm only, one full exposure, the full exposure needle turn yellowish.
It could also due to the potting medium, i would suggest you to join Internet Bonsai Club or bonsai nut, post u pic and ask the member there, or join Lindsay Farr world of bonsai in facebook n ask the friend there.
Some bonsai master will say, learned how to keep pine alive first before u bonsai them.
If the pine is undergoing stress, NEVER do an root pruning. pruning, cutting, or wireing.
NEVER NEVER NEVER, bare root a o pine
NEVER NEVER NEVER cut more than 1/4 of the root ball when reporting or root pruning, (especially the root with white tip)
NEVER NEVER NEVER bare needle a pine. If you bare a branch, pine does not bud from a branch without needle so the branch/tree without needle is as same as dead.
What you should do after reporting is just leave it for more than tree month before u do anything. Unlike other type of tree, do not needle prune when reporting.
What i sometimes do is i usually wire the tree in its original pot first, bend it to the shape i want then tree month later when the tree does not show any stress i report to a bonsai pot. However if the potting medium in the original pot is not suitable i will change the potting medium first.
Thanks again for the great info.
I'm a member of IBC too but not so active for the past 2 years. I think I should go back there.
However, info given by IBC member is more suitable for their country's climate.
So far in M'sia, you are the only one we know whom have successfully grow and train pine species even in a condo apartment under the M'sian weather.
It's very generous of you for sharing out the info. Look like a few of us here are going to put in quite some "investment" in the pines now.