Bumpstops, the short story...

[632 Regal]

http://www.bimmer.info/~regal632/bumpchop1.jpg
http://www.bimmer.info/~regal632/bumpchop2.jpg
http://www.bimmer.info/~regal632/bumpchop3.jpg

[632 Regal]

http://www.bimmer.info/~regal632/bumpchop4.jpg
http://www.bimmer.info/~regal632/bumpchop5.jpg
and they lived happily ever after.

[Dave M]

Nikolai Vodka, never seen the likes. Is it from Kentucky?

As a Vodka user, I may have to have you send me a bottle. I've had everything I can get my hands on in Canada.

Dave M

[genphreak]

Jeff are those stock rear bumpstops or are they a generic type?

I have been trying to work out the right theoretical length, ie height of the original bumpstop. Do you know what it was?

I say this as the most important thing to maintain is the bumpstop's compressed size as this is calculated to prevent suspension components reaching the full length of their travel and hitting things/each other/wrecking bushings etc.

S@#$!, it may even be different on a Bilstein shock if it's body was a different height... So I just went out the back to check- here is a pic (below). You can see that the Billie is a good 3mm shorter... its not huge, but it means it will travel 3mm further than the Boge- so the Billie bumpstop should be a whole 3mm longer than stock). What a ground breaking discovery... :| but at least stock Boge bumps are all that is needed; I doubt 3mm makes enough difference to worry anything.

My stock bumpstops had completely disintegrated (you can the shock in the pic was as old as the car when it came off- 17 years ;))... I'd love to know if anyone has got a real set of stock ones and can measure them up for us!

F@#$! Bilstein, why couldn't they get it right in the first place??? I tried to get a Billie bumpstop kit once, they (Aussie bilstein distributor) didn't know of one.


Jeff; re your pic, do you really think that glue will hold?

I like the idea of keeping both compression sections, but....

Under a hit of 1200kg at (who knows how many) metres per second the material will be squished to the max. I doubt the glue would deal with the amount of elasticity required to maintain a bond as the foam is compressed and flares out sideways.

If it separates the lower ring will drop down the shock piston and it may (but probably not) squash dirt into the piston seal as it gradually disintegrates from all the shoving up and down the shaft.

[genphreak]

Do you think jeff drank the majority of the bottle before or after he took glued 'em up? :D Nick

[genphreak]

Apologies everyone, I photographed the shock without the lower spring seat. If you place this 'hat' on the shock the body length of the shock to the bottom of the spring will work out the same as the stock shock. :)

All good. So stock bumpstops are perfect.

[632 Regal]

those are the front stops, originally they were 3.5 inches. I cut an inch out of the central section, this leaves a little over an inch of cushion plus the air cushon. The Bilsteins had 1 inch of cushon which was perfect as to not bottom out unless you hit a crater, I think this height will be good. I will pop the sachs in next weekend and give a final oppinion after about a week or so.

The glue is flexible, not as strong as I liked but should withstand the compression and events associated.

[632 Regal]

Dave it is a Kentucky made vodka, in researching it is about the cleanest you can get next to absolute which spends millions advertising its 4x cost product. I persanally, side by side taste sample cannot tell a bit of difference.


Nikolai Vodka, never seen the likes. Is it from Kentucky?

As a Vodka user, I may have to have you send me a bottle. I've had everything I can get my hands on in Canada.

Dave M

[Anthony (M5 in Calgary)]

http://www.bimmer.info/~regal632/bumpchop4.jpg
http://www.bimmer.info/~regal632/bumpchop5.jpg
and they lived happily ever after.


Dude!

http://img.photobucket.com/albums/v11/interalian/DSC00344.jpg

(2.9" M5 stoppers) Stupid expensive - my next R&R will use the cut-down $12 parts...

[632 Regal]

yea, 12 bux vs 45 each, quite a difference and with as often as i tear this front **** apart i will take the chance of the glue spitting.

Do you have any clue what this is and if its needed? I have another week to order it up if needed.

http://www.bimmer.info/forum/showthread.php?p=158903&posted=1#post158903

#11, dont seem to be needed on my car but wondering. One day I'm gonna be done with this front end ****.

New rotors cleared up 90% of the thrust arm bushing shimmy but still have a tad. On inspection AGAIN I cant isolate anything.


Dude!

(2.9" M5 stoppers) Stupid expensive - my next R&R will use the cut-down $12 parts...

[632 Regal]

the picture order is correct, the bottle refills itself.

Do you think jeff drank the majority of the bottle before or after he took glued 'em up? :D Nick

[genphreak]

those are the front stops, originally they were 3.5 inches. I cut an inch out of the central section, this leaves a little over an inch of cushion plus the air cushon. The Bilsteins had 1 inch of cushon which was perfect as to not bottom out unless you hit a crater, I think this height will be good. I will pop the sachs in next weekend and give a final oppinion after about a week or so.

The glue is flexible, not as strong as I liked but should withstand the compression and events associated.Ow! I thought those were the rear ones you were cutting down.

Are the front stops not inside the outer shock tube?

Or are these emergency stops in case the top stop disintegrates... :) I can't remember Kristian and I putting ANY on the front- and she bangs... not bad but she bangs... and I didn't hit a bad hole... yet. Looks like I have to install something like this too... no? One needs both?

Have you cut the rears down also?

Cheers Jeff, Nick

[genphreak]

Heh, thanks Buddy!! 2.9" of full-force bangin' bounce. I better get some. Only question now is, do I have to do the same as Jeff or can I leave them standard height- My springs do not slam the car like his have...

[632 Regal]

front stops are at the top where the shock attaches to the strut bearing. Only the Bilsteins have an internal stop as far as I know. You should have something in there, if it hits solid it could bust the strut bearing.


Ow! I thought those were the rear ones you were cutting down.

Are the front stops not inside the outer shock tube?

Or are these emergency stops in case the top stop disintegrates... :) I can't remember Kristian and I putting ANY on the front- and she bangs... not bad but she bangs... and I didn't hit a bad hole... yet. Looks like I have to install something like this too... no? One needs both?

Have you cut the rears down also?

Cheers Jeff, Nick

[genphreak]

front stops are at the top where the shock attaches to the strut bearing. Only the Bilsteins have an internal stop as far as I know. You should have something in there, if it hits solid it could bust the strut bearing.Ahhh thanks. You are putting the Sashs #199s in with those stops. Good move; I thought you were still on your Billie sports.

I don't have any stop on the shaft under the strut bearing- am relying on the stops in the shocks- if I did that would explain it as 2 bumpstops hitting would be damn hard as opposed to nicely cushioned. I get a good bang when I hit a bad bump at speed, and my car is at most an inch little lower than stock. As this was what you were describing with your wretched Billies, I was going to void my warranty (what is it worth anyway... ) and do this too-

Do you still think opening the shock up to cut down the lower bumpstop is the right thing to do?

[632 Regal]

you will void the Billies useless warrantee, maybe call them and mention that several people mention that the bumpstops are too tall for your vehicle? Cutting my billie stops down helped a LOT.


Ahhh thanks. You are putting the Sashs #199s in with those stops. Good move; I thought you were still on your Billie sports.

I don't have any stop on the shaft under the strut bearing- am relying on the stops in the shocks- if I did that would explain it as 2 bumpstops hitting would be damn hard as opposed to nicely cushioned. I get a good bang when I hit a bad bump at speed, and my car is at most an inch little lower than stock. As this was what you were describing with your wretched Billies, I was going to void my warranty (what is it worth anyway... ) and do this too-

Do you still think opening the shock up to cut down the lower bumpstop is the right thing to do?

[632 Regal]

the vodka induced bumpstops are holding up very well so far, I havent noticed ANY bottoning out at all with this setup. The car seems to have settled an additional 1/2-3/4 inch from when I first installed the springs. Need a new side picture soon.


Heh, thanks Buddy!! 2.9" of full-force bangin' bounce. I better get some. Only question now is, do I have to do the same as Jeff or can I leave them standard height- My springs do not slam the car like his have...

[Jon K]

Why not just cut them at the end. The unit is one big piece of foam, I really don't think the middle section vs the bottom section is going to make much difference.

[632 Regal]

there is a difference and yes it will
Why not just cut them at the end. The unit is one big piece of foam, I really don't think the middle section vs the bottom section is going to make much difference.

[Jon K]

there is a difference and yes it will


Why? The center section does not appear to be reinforced in any manner... I have always just chopped the bottom part off about 3/4" and am fine - in fact, I've never even had the car bottom out

[632 Regal]

i just like doing things the hard way.


Why? The center section does not appear to be reinforced in any manner... I have always just chopped the bottom part off about 3/4" and am fine - in fact, I've never even had the car bottom out

[Jay 535i]

Forgive my ignorance: what does this modification accomplish?

[Anthony (M5 in Calgary)]

Why? The center section does not appear to be reinforced in any manner... I have always just chopped the bottom part off about 3/4" and am fine - in fact, I've never even had the car bottom out

Because the bottom part is an air spring. Cut it off and you lose the progressive compression and just hit the hard foam. Besides, the bottom portion has the lip to secure the dust sleeve...

[632 Regal]

some cars with real low suspension cause the top of the shock to slam against the strut bearing so we shorten the stock bumpstops so the car isnt riding on them.

Edit: this explanation sux...

Forgive my ignorance: what does this modification accomplish?