Can someone help?

[confusious]

Okay,

Im experiencing some strange vibrations on the bottom rear area of my bike. Easily noticable from take off to 3rd gear where it disapears. It almost feels asif the backwheel is going over a gravel road or small speed bumps.
Would this have something to do with the misalignment of the sproket?
I have checked the teeth and they are fine as it was replaced under 1000kms ago.

Could someone help me?

[Goldmember]

It could be the chain or you lost a wheel weight thats causing that vibrations on the rear of your bike

[Like to ride (ZX900R)]

Sounds like the chain is loose or stretched. If it was a wheel weight it would get worse as you accelerate.
If you can jack it up check the chain doesn't have loose or tight spots while turning the wheel and check the tyre hasn't got a flat spot from a rear lock up or a bubble from delaminating or stress.
Also a while back I had a good quality Michelin tyre fitted by a local Honda shop and they hadn't popped the bead all the way out, I rode all the way to Geraldton and it vibrated when I slowed under 80kms, I was thinking it was the chain which they also replaced, the tyre was rooted and replaced when I got back

[Doc Martin]

Is that a true likeness in your avatar if so there may be another reason(can't put my finger on it there just maybe)!

[confusious]

Sounds like the chain is loose or stretched.

Yeah i measured the freeplay in the chain this morning and it was too loose, no tight spots. Thanks.

Is that a true likeness in your avatar if so there may be another reason(can't put my finger on it there just maybe)!

It maywell be, hah, i wiegh probly a tenth of that big boy!