unsettling vibration

[Tiababy]

So had my Tyres changed on my last day off (Tuesday) went on the motorway yesterday and noticed a steering wheel vibration that starts at just over 70 (The car had been on the motorway Tuesday morning with no issue)

Didn't have any vibration or trouble on my old Federals 595RSr. They are now shod in Contisport 3's and I've also noticed the handling isn't as spot on (whether this is down to the tyre being a different type or a result of whatever is causing the vibration I'm unsure)

I've checked the pressures as when the front drivers side was put on it made my TPMS flash up STOP! puncture. They had over inflated the tyre so I let some air out then stopped at the local garage to double check the pressures.
Running 33 all over as I did with the 595s.
Might change this after work today (32 front and 30 rear) as I think this is what recommended for town driving. Would running them at 33 rather then the recommended 35 be cause for the vibration on the motorway?
If messing with the pressures doesn't help would my next step be to get them balanced again (as they had been balanced for the 595s but not the contis) as this is an issue that has only arisen since the tyre change.

 

[KevF182]

Sounds very much like they are unbalanced. Did the tyre fitter not do this though?

 

[TheEvilGiraffe]

Why did they not get re-balanced when you had new rubber fitted !? :S

All it takes is a few grams to unsettle a wheel which is spinning at very high speed when you're doing 70mph...

 

[Tiababy]

If it wasn't for the fact they have been closed over Easter it would have already been back. To be honest I'd rather now take it somewhere where I know they will do it properly as I don't have confidence in the garage that put the new tyres on.
Taking some of the air pressure out seems to have lessened the effect it has. As soon as I find somewhere that's open it's going in. Just wish I didn't have an 10 hour shift at work to try an get it done around.

 

[Tiababy]

Just thought I'd update this as I did go and get my wheels balanced on my next day off.

Turns out my front passanger side wheel has, can't think of the word so shall say buckled, so the balanced it to counteract this until I can replace it (I have a set of 4 alloys at home as spares as I know these wheels are very easy to do this too)
Vibration isn't noticable now until much higher speeds as its only a very slightly damaged. Will be getting the tyre and TPMS valve switched onto my new alloy on my next day off.
Don't you just love shift work, such a pain to get your car sorted around.
Used National tyres in farnborough opposite the swan/airport. Really good service and the chap who did my wheels knew what he was doing. Will use them again rather then a certain KF who always try to get more money out of me.