15 replies to this topic

[tb205gti]

I have a problem with my mini (surpirse!! :))

When doing roughly 90 m/h in it, it starts to shake quite badly. it feels like it comes from the front left wheel. Balancing on the wheel is okayish, not perfect, but ok.

If I let go of the throttle, the shaking almost stops, also if I accelerate more it almost stops. The problem is worst when I'm just cruising at 90-95km/h.

Any ideas? is the bearing adjustable on the hub? (the mini is a 1977, 998cc). can it be poor bearing adjustment and a not so perfect balancing?
I'm running Chromodora 5x10 wheels and std. drums.

[rally515]

Could be a number of things to be honest, such as bearings, driveshafts Its obviously a problem which is in the drivetrain upfront

[tb205gti]

Could be a number of things to be honest, such as bearings, driveshafts Its obviously a problem which is in the drivetrain upfront

I didn't consider the driveshafts at all, they do not make any knocking, grinding or other unhealthy sounds when on full lock, nor when driving. But it could be them I suppose.

[konyo]

This happens to me too really badly when i come off the power, however if i floor it it then gets smooth again.
I just have to repump up my front tyres and its fine lol.. one of my front tyres has a slow punture so that causes it. Maybe the same with you?

Edited by konyo, 27 March 2013 - 12:24 PM.

[Gulfclubby]

I'm with DILLIGAF with this one. Most of the time if you can only feel it at high speeds, it's a small thing like uneven balance.

[jaydee]

Please dont be tempted to 'adjust' wheel bearings.
Take it to a garage that can handle 10" wheel and have them properly balanced.

[tb205gti]

I'm with DILLIGAF with this one. Most of the time if you can only feel it at high speeds, it's a small thing like uneven balance.

It is not normal poor balancing, this is far more "violent". The whole car shakes and judders, if it was just a poor balancing, it would just shake a bit.

[jaydee]

Are the wheel nut torqued correctly?
'Whobbly' wheel bearings are usually noticeable under braking, shuddering at speed sounds like something to do with wrong balance

[Gulfclubby]

It could of course be a case of bad tracking too. But it'd have to be serious to be noticeable like that.
Jack it up and grab the front wheels and see in what directions you can move them.

[Cooperman]

Check wheel balance, track rod ends, tie-bar bushes, lower arm inner bushes, steering rack nuts (inside the car), steering shaft to rack bolt.

[tiger99]

And the subframe mounts, especially to the toeboard. They often fail, unless you have fitted a solid kit.

[carbon]

I had a similar problem quite a few years back, with a set of Astrali alloys. Really rough at speed, took the wheels in to get balanced several times but could not get to the bottom of the problem. Finally chocked up the front wheels and carefully spun it up, it was jumping around and really obviously out of balance.

Turned out that the holes for the wheelnuts had not been properly centred in one the alloy wheels, must have been when they were drilled at the factory. As a result this wheel was running out of true.

Centre hole was OK, which is why this was not picked up by balancing...

Would recommend that you check at the rim for any run-out, should be less than 1mm.

[tb205gti]

A small update from me. I checked the tire pressure (just to note, It has been stored for nearly 5 months now, I have not been driving in it since November). But one of the wheels was at only 1bar. I gave them all 2bars. It shakes a little bit now, but nowhere as much as before.

Bad balancing combined with too low tire pressure may have caused it to shake. I'm waiting on my new wheels from R&R Alloys to see if it also shakes with them. If this is the case I need to look into some of the other things suggested here.

Thanks for your input :)

[Jmccrary]

TB, I never thought about the tire pressure...mine has a bit of a shake in it around 45-60 mph...may have to check the pressure...was also thinking about the tq of the nuts...i too am looking at getting new wheels so may wait...

[jaydee]

uneven pressure wont cause shaking unless one of the tyre is actually flat, but will accentuate any juddering caused by wrong balance
wheel nut torque setting is about 60-62 Nm