I apologize for this general question.....

My father is going to be shooting a 2004 Mathews LX this fall. He has been told that he needs to change the bottom cam to fit his draw length.

Does this mean he will also have to purchase a new string?

He is probably just over any adjustablity for draw length in that first cam.

What his exact measurements are...I am sorry, I don't know. I am more looking for a hard rule that says once you change cams...you have to change strings.

Any help would be greatly appreciated.

MD,
This might be just the source for info you are looking for to help with that bow:

http://forums.mathewsinc.com/

You do not have to change string/cables on that bow once you change cams. That cam is also draw length specific. You can get small amounts of adjustability out of it by twisting the cable (twists in to lengthen, twists out to shorten) but only maybe 3/8" or so. Mathews makes cams in 1/2" lengths for draw length. Your best bet is to call your local Mathews shop and have them fix you up with the correct cam and then retime the bow for you.

Make sure you're not going to change the draw length more than a couple inches. I just ran into trouble trying to get a 4" change out of a Mathews, the limbs overload and jack the poundage through the roof.

I'm not sure about that bow specifically, but SOMETIMES when you change cams you DO need to change strings and cables.....

I would doubt if you need to change the string as long as you're only changing it a couple inches.

No this is far from the worst question ever

But what ever you do get a string and cable from gibblet here on the forum dont let them put a zebra on it.

Does anyone kno about doing this with a hoyt vetrix? Form 27 to 28. I didnt think i would need to, but just wanna make sure.

Not sure about string replacement? My HCA carbon four runner (2000) came with a 29"-30" DL. I changed the lower cam to give me a 28"-29" I didn't have to change strings, I just had them set it at 64 lbs DW after cam was installed.
crutch

You definately do not need to change the string.