Same dt125r ......new problems !!!

Firstly thanks for all your help with my last problem !

Now onto my new problems

At about 5000 revs and onwards im getting some major vibrations so much that after a short trip my fingers on my left hand go numb.

This particular problem started about 2 weeks ago

The temperature guage has gone close to the red

This problem started about a week ago

It feels like it has Kangaroo petrol in it its spluttering and jerking and really doesnt seem happy at all ....tonight it cut out but started running again straight away.

And this problem only about 3 days ago

I dont thrash the bike i use to commute to work and i do about 25 mile a day and never go over 7-8000 revs and never more than 70

I always use the same petrol station so i wouldnt think the petrol is the problem

Ive replace the coolant

There is correct amount of engine oil in

There is plenty of 2 stroke oil in.

Any ideas

Thanks in advance

Mark