new front tyre fitted , problem ?

[steveg]

Hi ,
Got a new front strada fitted today , rear is about half worn .
Sometimes when I roll off to lower speed limits take both hands off the bars & stretch , noticed that since the new tyre has been fitted the handlebars wobble at 40 - 50 mph slightly , not massive but not noticed before , under 40 mph & is fine , with both hands on handle bars fine .....
Not sure if its anything to worry about as is fine apart from the hands off shake at 40 -50 mph ?
Have checked tyre pressure ok , tyre is seated on rim ok .
Wonder is its because the rear tyre is half worn , with a new front ?
Or is the front balanced incorrectly , if so I would have thought I would have felt it at all speeds ?
What do u recon ?
BTW The place a got tyres from is 100 mile round trip

Cheers Steve

[Stu]

A wobble at a particular speed would indicate the tyre is not properly balanced.
take it back
Or if you want to satisfy yourself, remove wheel, support it through the axel so that it spins freely, ensure it doesn't always stop spinning at the same place (as that would indicate it's not balanced.

[Viney]

It can also be other things, head bearings, tyre pressures etc can all cause what you are desctibing. You probably didnt notice it before. It can aslo be where you sit on the bike. Try leaning forward a little thus bringing more wieght over the fornt wheel and see what happens.

[steveg]

took it back , bought tyre originally from Mick Central Wheel B'ham , took it to branch @ pershore ( did not know they did tyres) , Turns out I know the mechanic there Wiggy , he took wheel off , head bearing , checked seating etc & balance all fine .
Still got 50 mph hands off shimmer , to be honest it might have been there before and never noticed !

At least I've had a 2nd opniON , used Central Wheel B'ham for years & they are a top bunch who know their stuff .

Cheers Steve