View Full Version : Lets talk shims...

05-03-2013, 11:13 AM
So the idler wheel on my 2012 Pantera has developed a vibration/buzzing and I'm suspecting a shim issue. I already pressed it and moved the idler checking for any play to try and eliminate a bearing problem (hoping its not the bearings). I got a shim kit from Martin and will be doing the work tonight. Does anyone have some input on this whole process or about the problem itself? I am very mechanically inclined by trade but nonetheless this is my first attempt at this. Thanks for any help.

Sonny Thomas
05-03-2013, 11:32 AM
Top wheel? Pressed, string off, spin the wheel. It should spin for a bit and no stutter stuff. Normally, you can roll the wheel, starting with the heal of your hand and roll right off the finger tip. Any "clunk" feel, then a bearing. There can be a certain amount of play on the axle when holding the cam and trying to test it towards either end of the axle - not much, but a ever so tiny bit. If it shakes quite a bit then possibly a bearing.

Side to side play within the limbs, maybe, but rarely. For a wheel have equal amount of shims or same size on each side. Normally it's a little stubborn to shove all in if all is correct, but generally all goes in. If you have to force some, then probably too much shim.

Okay, no rocket science involved, just common sense. Don't feel it's right, call Martin.

05-03-2013, 11:43 AM
Side to side play in limbs..hmmm. Funny you bring that up because I thought about it and then brushed it off thinking there's no way. When I bump the riser the whole limb and idler wheel vibrates and buzzes and I can feel it after the shot. I did roll the idler wheel and it didn't spin freely but also didn't feel like it was sticking or clunky. Oh boy this is going to be fun trying to track down this problem.

05-03-2013, 04:34 PM
This may go with out saying, but did you check the limb over to make sure there are no cracks? Bearing issues (I believe) are far and few between, shims, I haven't had any problems with; could be an issue but I'd suspect you'd have noticed if it was shimmed wrong from the factory to begin with.... I'd check over the limb with a fine toothed comb, or at least some cotton balls. ;)

05-03-2013, 04:38 PM
Well just got done putting in new shims and no luck. The idler wheel doesn't just freely spin but it doesn't seem bad to me. I can spin it and it will get about one full rotation and stop. Bearings? I will definitely check the limbs out, I already have but no hurt in double checking.

05-03-2013, 08:34 PM
Well there are no cracks or anything with the limbs. I went out and shot for about 3 hours and it shoots great still, broadheads right with field points. Buuuuut, the buzz and vibration are still there....I'm stumped?

Sonny Thomas
05-03-2013, 09:05 PM
Check accessories, quiver, stab, sights. Heck, don't bother checking, just remove and try a shot, that's the fastest way to find out.

05-03-2013, 10:27 PM
I know you said idler but i would check your module screws sometimes they get loose and are pretty loud and sound just like your explaining.