Chain Tension, After Research..
 

I have noticed a vibration in the left peg which I found little info about. I swapped bikes with my buddy and noticed there was a ton of free play at the bottom of my chain..? I had the chain tension set right around 1 inch. The specs of 1 1/4 is way to loose I have heard from experienced riders. Could my chain be off a sprocket tooth? Could that contribute to the vibrations?

Ive had the same problem with my bike ever since i got it. I can feel some vibrations in my left peg almost as if something near it is rubbing or grinding on something else. You cant really hear anything and its not a big vibration its just one of those things you only notice when youre paying attention to it. I figured it was my chain too but tension was in spec and i couldnt find or notice anything else that was wrong that could cause it. Ive just been ignoring it though so since i havent had any problems. If you solve it let me know cuz ive been stumped.

The chain slack is the total deflection from all the way down as far as you can push it to all the way up as high as you can lift it, measured in the middle of the bottom half of the chain. My owner's manual calls for 1-1.4" of slack. I have it set to around 1.25" and it feels about right.

Yeah i had my buddy hold the bike up while i measured and it was just a little over 1.25". Maybe ill tighten it to around an inch and see if that helps.

Check tire alignment. Sight down the chain and be sure it's a straight line.
If you are concerned about chain slap from improper chain tension look for rub-marks. Seems obvious, but is the chain being lubed regularly? I frequently get 20k to 30k on mine by lubbing every tank of gas. Check wheel bearings as well as "free-float" of the rear brake caliper. It should be able to slide on the hanger bolts. If it's hanging a tiny bit, might be rubbing the rotor instead of backing off like it should.

That's about the only moving parts, I could think of, that might cause a rear vibration.
Ern

Thanks guys. Shouldnt the slack on the top of the chain be the same as the bottom? The more and more I think about it.. I think that my chain could be off a link on the sprocket.. I dont have and slapping going on just seemingly to much slack on the bottom screwing up my adjustments. I still swear 1 1/4 is way to much slack. Go by your local dealership or performance shop and check their tensions.. they are pretty darn tight. Less than 1''

Mine did that for a while too. It turned out on mine it was the shift rod pivot joint on the shift lever was rubbing my chain just a little bit. It was mainly the rubber gromet thing that was rubbing. I don't think that's what your issue is since i had a broke rear set and it was welded back a little off soni changed the rear set and bam problem solved. Check and see if it rubs if so that's more then likely the issue.

the chain will be tighter on top if u are in gear and it was stopped under load. when u put it in neuteral u should be able to put top and bottom towards each other so they are the same(the primary sprocket would turn backwards). chains can stretch unevenly. this could cause a vibe. your chain cant be off a tooth. it can skip a tooth but unlike a cam chain, it cannot be off a tooth, since there is no index point..

Hondas factory spec has worked fine for 47,000 miles for me. Too tight and you'll bind the suspension and kill chains and sprockets at an amazing rate.

If you over tighten the chain when you fully deflect the suspension the tension may be way too tight. Better looser than tighter.