I've been battling condromaligia patella for two years, sharply curtailing my riding as I perform a regime of strength building exercizes.

Now I am preparing to alter my equipment and I need some advice. I have a
Trek 5200 with a double chain ring, which I am considering changing to a triple
chain ring to take some of the stress off my knees when climbing. This is very expensive (about $600 or $700) and the fellow who runs my bike shop mentioned
something called "compact cranks" that offer fewer options than a triple
ring, but more than a double.
Has anyone heard of these "compact cranks?

Also, I have red Look pedals on the bike and use Poggio shoes. I'm wondering
if this combination is too aggressive and if I should switch to a pedal and cleat system that might spare my knees some friction.

Any guidance on pedal and shoe choices or any related matters would be greatly appreciated.

a compact crank is a crank that has smaller rings (usually a 50/34 or 35 compared to the usual 53/39). this allows you to achieve lower gearing that is comprable to a triple without sacrificing shifting quality or weight (although this isn't a major concern). going to a compact is defidently cheaper than switching to a triple. Check out the FSA line if you decide to go that direction. I don't think you need to worry about your pedals, but you may want to use the cleats that allow for float. Look style pedals come with two types of cleats (you may haave to buy the second type seperately). the first locks your foot into place and does not allow you to rotate your foot any while you are clipped in. The second type allows you to rotate your foot a certain amount (with look, i think it is 6 or 9 degrees) while you are clipped in. This rotation is called float. having several degrees of float can help to spare your knees. You may already have the float cleats, but you still need to make sure that they are positioned properly on the shoes. You may also want to consider spending the money on a professional fit, this can help a huge deal with knee issues and they can further advise you on shoes/pedals/float based on your body mechanics.

I'm not sure that lower gearing would be a huge help, isn't NY pretty flat? I could be totally off here. The difference is in you, you need to spin lower gears. I'd go with a lower-geared cassette first before spending the big dough on a crank. cassettes are ~$40, a crank is gonna be at least ~$100.

Also, a good warm-up is essential, for the first 15 minutes of a ride, put it in the little ring, and dont even think about touching that left shifter.

as for the cleat confusion, the red cleats are the floating ones. I think your pedal/shoe combo is fine, i'd look for a fitting though.

The most important thing is to rest for at least a week. take a week off and dont do ANYTHING! Then go for the fitting. then take it easy for a week or two, with lighter riding. You should be good as new in a few weeks.

Thanks fo your helpful replies.

The compact cassette my bike shop is pitching is Shimano's XT. It's actually made for mountain bikes, but supposedly it's now commonly used on road bikes. It's got 34 teeth in the back.
Have you guys heard of this?

if you want to go to a 34, you would have to get a new rear derailer as well. there's nothing wrong with that, but it sounds like the shop may be trying to get you to spend more money. What's your current cassette? Also, you can probably just keep using your regular front derailer and simply move it down a few mm's. a 34 crank with a big cog of 25 gives you 35.9 gear inches (the fewer gear inches, the easier it is to push, so the lower the gear inches, the better it is for climbing). the 34 with a 34 gives you 26.4 gear inches. a normal triple with a 31 tooth crank and a 25 tooth cog gives you 32.8 gear inches. so the compact and the triple are pretty close, and the 34/34 cobo is way lower. If you can handle hills with a triple, you can probably handle them with a compact. also, on shimano's road stuff, you can go up to a 27 cog on the back (i think), giving you even lower gearing with 33.3 gear inches. going to a 43 cassette rear is probably uneccesary. i recommend that you switch to the compact, try it for a while (at least a week or two), and then switch to the mtn. cassette and derailer if you really need to.