Shakes @ 50-60 MPH

[pat_986]

Over the last year, I have replaced loads of parts on my Valver, I like to get things replaced before they can go wrong.

The problem I have now is a severe shake on the steering wheel when braking, It is at its worst between 60-50MPH.
The disks are about 3000miles old, same as the pads, front wheel bearing's, and bushes............I also replaced both drive shafts last weekend.

Is it the disks that are warped?? I think this is the cause but I don't understand why the wobble is at it's worst between 60-50MPH and not at higher speeds, I also made sure they were well bedded in when new, before any hard braking.

Any ideas???
I have also just had the front wheels balanced this weekend.

Thanks

[GTI-Russ]

Tracking? Had that promlem in my old BM. used to shake like crazy at 60mph but was ok at 70.

But then again that was'nt under breaking, tis just an idea mind :wink:

[pat_986]

Yeah, could do tracking, think it must be disks as the main culpret though!

[diggs04]

tracking and wheels need balancing. :lol:

[VIPERONE]

make sure your wheel nuts are tight, your tracking is sorted and that your wheels are not buckled

[pat_986]

Thanks guys, Wheels were ballanced this weekend, and obviously done up tight.......................The tracking.....this wouldn't explain why it is only doing while breaking though....would it???

I have just ordered some Brembo MAX disks, so will fit these with new pads+get tracking done, and see how I get on from there.

Thanks for all your help.

[VIPERONE]

apologies.. i had warped discs.. and a symptom was shuddering when braking at high speed

[pat_986]

apologies.. i had warped discs.. and a symptom was shuddering when braking at high speed

Thanks mate, I'm 90% sure it is warped disks, just unsure of why 60-50mph causes the wobble?? Well I will see what happens witht the new disks!

[Amirclio]

What wheels have you got on? Are they a tight fit over hub? You may need some spiggot rings if they arent tight. I had this problem on my previous clio, after market wheels with a small gap where the centre of the wheels fitted round the hub. The spiggots fill this gap (looks like a doughnut) making for a tight fit.
Amir

[pat_986]

There standard phase2 wheels.

[Anders]

The shudder at a certain speed is all to do with the natural frequency of resonance... everything has a certain frequency of vibration...like pushing a young kid on a swing...

It could be a number of things, wheel balancing, warped discs etc... If you are sure it is warped disks, then you can tests for this by slightly braking and seeing if there is a variation in braking force as the wheel rotates..so when the warped bit passes through the calipers you should be able to feel more bite..it probably gets more noticeable the slower you go.

Another thing could be slightly misaligned discs, seen a few before, ie the not centred rotating mass will give you a vibration at speed.

[pat_986]

Thanks for this mate.

I have had the front wheels balanced, and I will fit my new disk's this weekend. I have orderd some Brembo MAX disks so I hope they are high quality..............or at least better than the crappy ones I have now from good old ebay!!

[VIPERONE]

Have you checked the hub nuts? 30mm socket