Unstable car after fitting different alloys?

[aztecbandit1]

Put my 18" alloys on the Lexus is200 on Saturday, and now the thing feels like it has very light steering, slight vibration at around 70mph, and very unstable above that? The oem alloys had 225/45/17 on the front, and 235/45/17 on the rear and felt very well planted when driving? now its fitted with 225/40/18 tyres and its horrible?

 

The spigot rings that were on the were too big (73.1 - 65.1) so fitted some new ones today 73.1 - 60.1mm (Lexus size 60.1) which has helped a little but still feeling very disconnected at speed above 50mph?

 

Have had a little search about the site for similar problems and a few i've come across have mentioned the balancing of the wheels? would this cause this type of problem? the old wheels were standard lexus alloys with an offset of 50, and the new alloys are a 42? offset..

 

Any help would be great as its quite annoying and feels quite unsafe to drive?

 

Thanks

[adam_r]

Put my 18" alloys on the Lexus is200 on Saturday, and now the thing feels like it has very light steering, slight vibration at around 70mph, and very unstable above that? The oem alloys had 225/45/17 on the front, and 235/45/17 on the rear and felt very well planted when driving? now its fitted with 225/40/18 tyres and its horrible?

 

The spigot rings that were on the were too big (73.1 - 65.1) so fitted some new ones today 73.1 - 60.1mm (Lexus size 60.1) which has helped a little but still feeling very disconnected at speed above 50mph?

 

Have had a little search about the site for similar problems and a few i've come across have mentioned the balancing of the wheels? would this cause this type of problem? the old wheels were standard lexus alloys with an offset of 50, and the new alloys are a 42? offset..

 

Any help would be great as its quite annoying and feels quite unsafe to drive?

 

Thanks

 

Not wanting to have a 'go' at you but you are VERY silly for driving on alloy wheels that dont have the correct spigot size (without the adapter). this puts a huge amount of stress on the bolts and i have known wheels to come off due to this, where the wheel bolts shear.

 

Have you had the tracking / geo done since you fitted the new wheels ? its silly to say but you might have knocked something slightly ?

What tyres do you have fitted ?

 

Sorry i cant be of much help but im pretty sure your feeling is down to a tyre or tracking issue.

[Rich]

Are they new wheels/tyres? Maybe they just need to scrub in first and that's causing the light steering?

[Tony]

Jack it up and spin the wheels, this way you can see if their hub-centric.