Rear Bumper Under Riders

[tmh]

The rear bumper under riders on my 73 CS were rotting/rotted away as they were sealed against the body. I just had the small rust spots on the body they were causing fixed. I see many cars on this site without them.
Are they supposed to have drain holes or somehow be watertight?
Is it a detriment to the value of the car to simply leave them off and smooth out and repaint their mounting point?
What is the proper way they should be mounted and attached regarding the rear bumper and the body of the car?
Does anyone have a set for sale?

I appreciate any feedback. I did try to search the subject but only found limited information rather than a thread addressing my various questions.

 

[scottevest]

I am anxious to hear the response to this question. My underwriters are off and I prefer the way it looks without them

 

[bavbob]

I have none and don't plan on getting them. I really cannot imagine they do anything other than be cosmetic and if you don't have/want a show car, then it depends on your taste.

 

[rsporsche]

as i remember - yes, there are drain holes on the underriders. they are small holes, so they could clog up easily. about 1/16" diameter. maybe 3/32"

 

[HB Chris]

If yours is a US 73 it also has a large rubber spacer between the chrome and the body. Those parts re long ago NLA but someone on eBay sells stainless replacements. They are a pain to remove as the bumper has to come off with them attached.

 

[Ohmess]

I like the look with the underriders.

On my 72, they are designed to be installed up against the body with small drainage holes to allow moisture to escape. These only allow modest amounts of moisture to escape, and if they clog, the underriders do not dry out and they rust from the inside.

Once I found a good set of underriders, which took me a couple of years, I did not install them tight against the body. Instead, I used a handful of washers so as to set them off maybe 5mm from the body - just enough to allow lots of airflow around and behind the underriders. In theory, this should help preserve them for a much longer period of time.

 

[scottevest]

Do they serve ANY purpose or purely cosemetic?

 

[Drew Gregg]

I have a '73 with the extended rear bumper and the rubber spacers. The under-riders have holes in their bottoms. I had one decent one and one very rusted that was replaced thanks to a forum member. After getting it re-chromed and several fixes to the previous jury-rigged way they were mounted,all is now correct. My advice is to fill the mounting holes in the body and leave them off of the rear bumper. The only purpose they serve is to catch water & debris coming up from the rear wheels while rusting again. Spend your Coupe $$ on other parts of the car. Here' a pic of my car w/o the rear bumper. You can see the holes for the under-riders in the bottom apron.

 

[Drew Gregg]

If you are not a purist and want a really cool looking rear, find a way to route exhaust pipes through the under-riders like on a '57 T-Bird. Then they will really serve a purpose.

 

[Ohmess]

Scott - they are purely cosmetic.

Drew - they are more securely mounted with a bolt through the body mount holes in additon to the bumper mount.

I love the idea of routing the exhaust through the underriders; post pictures when you do this.

 

[teahead]

BMW E9 rear bumper horns | eBay

Price for pair (2 pieces).

www.ebay.com

 

[Honolulu]

The bumper under-riders are cosmetic.

So is the bumper on early cars.

 

[bavbob]

Anyone who has removed their pre-DOT bumper knows it is cosmetic based on rigid mounting and its weight. My advice is to never do this because you will then be scared to death to drive your coupe, not for injury to you, but injury to the bumper. While I am not a DOT fan, making a more substantial bumper was warranted.

 

[tmh]

I am buying the set of Ebay. Making sure they drain as they are supposed to is a lesson to learn. Like the lesson I learned about the sunroof drains working as they are supposed to. When I had my car restored in 1991 the rear bumper was rechromed to a high finish and assembled. Over the years the bumperettes just kept rusting from the inside. They basically fell apart in my hand recently. Stupid me not to inspect them. I had never realized they were securely fastened and sealed up against the body, collecting water. I had always assumed they were fastened to the bumper and water would run off of them. The rest of the bumper has been fine.

 

[Ohmess]

Anyone who has removed their pre-DOT bumper knows it is cosmetic based on rigid mounting and its weight. My advice is to never do this because you will then be scared to death to drive your coupe, not for injury to you, but injury to the bumper. While I am not a DOT fan, making a more substantial bumper was warranted.

Once the DOT was able to mandate 5 mile an hour bumpers, automotive design was ruined. We've all had the experience of departing a classic car event and heading back into the everyday world of depressing, ugly automotive designs. And let's not forget the truck hoods, which now stand high enough that if you get stuck parking next to one in a car of any kind, you cannot see over them to get out of your parking space.

 

[Stan]

If you are not a purist and want a really cool looking rear, find a way to route exhaust pipes through the under-riders like on a '57 T-Bird. Then they will really serve a purpose.

I think you would need to make custom under riders large enough to accommodate a 60mm tail pipe. Then to balance, a custom final muffler with dual exhaust. Would look cool another member did something like that with Remus motorcycle mufflers.

 

[Koopman]

The rear bumper under riders on my 73 CS were rotting/rotted away as they were sealed against the body. I just had the small rust spots on the body they were causing fixed. I see many cars on this site without them.
Are they supposed to have drain holes or somehow be watertight?
Is it a detriment to the value of the car to simply leave them off and smooth out and repaint their mounting point?
What is the proper way they should be mounted and attached regarding the rear bumper and the body of the car?
Does anyone have a set for sale?

I appreciate any feedback. I did try to search the subject but only found limited information rather than a thread addressing my various questions.

 

[Koopman]

I wonder if undercoating would be an answer to the rust problem?

 

[eriknetherlands]

I think the ones from ebay (werent't they from Lithouania?) are stainless steel. Still it would be good to check the drain holes once a year or so.

 

[teahead]

I think the ones from ebay (werent't they from Lithouania?) are stainless steel. Still it would be good to check the drain holes once a year or so.

I don't think so. NO mention of SS.

Plus:

“Base is restored as new. Tripe plated- copper/nickel/chrome”