wicked lawn mower vibrations

[peacefrogx]

I'm assuming this is a fairly easy problem for this board to help me out with. I have a relatively new lawn mower (21" 7.0 hp self-propelled with a dual blade for mulching ), used maybe a dozen times. The first couple of times I used the mower it was as smooth as silk. But subsequently, it now vibrates to the point that after a typical 45 minute cut my hands are numb and sore from holding onto it . It cuts fine but I was just wondering if anyone could suggest what might be the problem and a possible solution. I'd rather not take it into the shop for something I feel can be self-diagnosed and corrected at home. I'm just looking for a little direction as to what the problem may be and where to start looking.

Thanks

[J.Gordon]

Have you sharpened your blades lately? I would guess that they are out of balance. A unbalanced blade will also rob a lot of horsepower. Check out the Maga-Matic balancers. http://www.magna-matic.com/

[Cleanmaxx Brian]

You have a blade that is out of balance. This if not fixed will tear up the bearings as well!

[SteveInMD]

I'm having sticker shock over the Magna-Matic balancer. They seem to be very proud of their products. I'm sure they work very well. Can anyone recommend a product for a small operation?

[bigz1001]

Start simple. Are all bolts tight? Are any bolts missing? Is a blade bent or broken? Are the blades balanced? (Much cheaper to contact local shops and pay a few dollars per blade to have them balanced than to make the investment yourself as a homeowner.) Have you hit anything with the mower that could have warped the deck?

[RKISTNER1]

Fill a bucket up with water. Take blades off ,then stick a screwdriver thru the hole. Then hold above water then ck 2 see if one side hits b4 the other.