Restoring Sun-Damaged Teak Chairs  

An
application of teak oil with fine-grade steel wool should do the trick!
Lovely chairs.

dvs, a 'gentle' sanding may work towards bringing some deeper colour to the timber. Due to the construction of the model 71 you should be careful with the backrest as this is the only part of the chair which is not solid timer, it is produced from a veneered laminate.
I would clean the chair thoroughly with fine wire wool dipped in spirit to remove any grime and wax build up and then try repeat applications of good quality teak oil, often this is all that is needed to bring back the colour to the timber.
Sanding should be your very last resort.
BTW the seat weave on your chair is not to the original design, there is a very comprehensive thread on here regarding Danish cord just in case you are feeling crafty.

thanks!
appreciate both notes. and yes, absolutely, to the current seat. main plan is to restore to the original danish cord. but wanted to make sure not a waste of time if can't also correct the sun damage, which i agree should be doable. thanks again!

Seasoned time travelers
I've had a fair bit of experience trying to address sun bleaching of aged teak and teak veneer and results seem to vary from piece to piece. The steel wool & spirits method certainly won't harm to the piece, but sometimes UV fading seems to penetrate surprisingly deeply into the timber. My rule of thumb is that if it doesn't clean up with a gentle scrub, as suggested above (you can also get a gentle light-grade scotch-brite pad which doesn't shed it's filament like steel wool) - then it's not meant to and that's just the character of the piece. Even an unevenly faded patina is generally seen as preferable to a freshly sanded finish. Remember, these chairs are design classics and no one expects them to look like new.

Orange Oil
Rub in with a soft cloth,you'd be surprised how rich the color becomes!