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Gary Kinghorn
26-09-2006, 12:37 PM
I know I know stupid question but hey i'm good at them :lol: ............

The bump stops in both my 205 and my beemer sit ontop of the struts. I guess thats pretty much standard. There is nothing remotely close to them which they can be buffering against.........So what are they there to do?

Gary

Dave Malings
26-09-2006, 12:40 PM
When your suspension fully compresses it stops the metal on metal noise you might get without them :thumb:

Simon
26-09-2006, 12:41 PM
Stop the body meeting the suspension when you drive over a major surface change (ie the Karassell).

Gary Kinghorn
26-09-2006, 12:48 PM
Two very different answers there ............

Simon ......... I cant see it, the body is around 6 inches from the bump stop, it was my original thought but I would be suprised if it drove up that far or the body down that far. Of course you could well be right though :thumb: For the road to hell I guess ;)

Dave ........ Its a dome shape which point straight up from the top of the strut (like a cone head :lol: ) so I cant see your idea being correct.

Dave Malings
26-09-2006, 12:58 PM
Maybe this is not a bump stop then?

Simons explanation is pretty good.

Dave G
26-09-2006, 01:34 PM
I think you are just referring to the 'dust cover' which is incidentally a coont to get back on!

:thumb:

Gary Kinghorn
26-09-2006, 01:40 PM
Originally posted by davetouring@Sep 26 2006, 02:34 PM
I think you are just referring to the 'dust cover' which is incidentally a coont to get back on!

:thumb:
Thats the fella Dave and yes they are ........ hence the reason they are sat in the rear well rather than on the struts ;) On the 205 they are definately called bump stops as thats what they were supplied as when I bought my poly bushes :thumb:


New rear top mounts arrived at lunchtime ;)

Darren Langeveld
26-09-2006, 01:42 PM
It prevents the strut compressing completely in the event of a big shock (i.e. a FG jump) Think of it as the last chance saloon for the structure of the car ....

I fitted lowered springs and shocks to the front end of a 205 GTi I used to own but used the standard bump stops. When I put it all back together and dropped it I realised that as the springs were shorter the bump stops were now too long, and the car was riding along on them. A little stiffer than I first intended !!!

Rather than dismantle the SOB's I simply enlisted my trusty soldering iron and melted through them at mid point to remove the top half from the strut. Bingo! I had some travel back!

Pooky
26-09-2006, 05:10 PM
Bump stops perform a few functions depending on the car. For some they are simply there to prevent the suspension crashing where it suddenly runs out of travel as others have stated.

For most road cars they should be called spring aids or assistors because they are developed to work with the springs to stiffen the suspension as the wheel moves into bump. This is both for ride to absorb larger bumps better and also to cope with changing loads, i.e. when you have a car full of people and luggage the rear suspension will permanently contact the bump stop to stiffen the suspension. They also work for handling where they come into contact during cornering stiffening the front axle for example to promote a healthy amount of understeer.

It's normally easy to tell what your bump stops has been developed to do, if they are fairly long and soft then they will be working as a spring aid.

Gary Kinghorn
26-09-2006, 07:12 PM
Thanks Pooky / Teflon and the rest of you.

From memory the poly versions on the 205 are very hard, whereas the std items on the 325i are soft as anything........

Some interesting replies though guys :thumb:

Gary

Floyd
27-09-2006, 09:05 PM
Bump stops are considered part of the suspension. The length and density should be closely matched to the spring length and ride height. Some companies don't have a clue about this :angry:

The bump stop is there to stop spring bind on full compression. It acts like a buffer as said earlier as well as other properties.

F

Pistonhead78
27-09-2006, 09:25 PM
Originally posted by Gutmann pug@Sep 26 2006, 12:37 PM
I know I know stupid question but hey i'm good at them :lol: ............

The bump stops in both my 205 and my beemer sit ontop of the struts. I guess thats pretty much standard. There is nothing remotely close to them which they can be buffering against.........So what are they there to do?

Gary
its when ur sus has reached the end of its travel, its the last thing that prevens ur suspension embeding itselfe in ur roof lol