Tuned pipe header spring retaining holes getting worn

[Kez]

The Picco exhaust header is held to the motor with a retaining spring as does CMB. The spring digs into the aluminum header and the holes become elongated and will eventually wear through. I don't want to be replacing the header every year. Is there a better way to keep the holes from wearing?

Thanks, k

 

[Hydro Junkie]

What about putting a 2-56 sized washer on the pipe side of the holes? Silver solder them on and it should strengthen the flange material and slow the damage down

 

[Danny King]

Stretch the spring so it isn’t so tight

 

[Mark Bullard]

Get rid of the holes on the header. Make a ring out of steel that will fit over the header tube loosely and that is larger than the part that slips over the exhaust of the motor. Drill two holes on each side for the spring. This is the way Rossi did many years ago and they never wore out. A Lathe make it easy to make these with a tube and using a parting tool.

 

[Walt Barney]

I just drill another hole in the header and when the original one wears out use the new holes, I have a header on a 21 that is so old that I have drilled it twice, on each side
Walt Barney

 

[Tom Foley]

Sometimes I'll put a blob or two of weld on the lip and reshape , lasts for a very long time .

 

[Kez]

Thanks Guys for your replies.

Mark, I cannot silver solder steel or SS to aluminum. And 2-56 washer is too big for the flange anyway. But your idea is similar to one I thought of, which is to enlarge the existing holes and JB weld the smallest K&S brass tubing into the holes.

Danny, stretching the spring probably won't help as it is the vibration that is doing the damage. It is happening to both .21 and 45 size headers

Mark, I like the idea. I will do a drawing and ask a machinist to make the ring for me. If I could not find someone to make the ring at a reasonable cost, I am thinking of using 1/16 piano wire to form the ring and then silver solder two little loops for the retaining spring.

Walt, I think your idea will work as well. However, the holes are smaller than 1/16. Not only these jewelry bits harder to come by, I am not sure if they can drill through that much aluminum without breaking. Where did you buy the bits?

Tom, I do not have aluminum welding capabilities. So it is not an option for me although I like the idea as it is the simplest solution

Thanks, k

 

[Hydro Junkie]

Kez, the only place I know of that carries bits that small is Micromark. The webpage for one of the sets is
https://www.micromark.com/20-piece-Micro-Size-Drill-Bit-Set-with-Index-61-80

 

[BobHorowitz]

MSC direct or Carr McMaster for drill bits. Both have have great web sites.

 

[Daniel's Racing]

Kez, the only place I know of that carries bits that small is Micromark. The webpage for one of the sets is
https://www.micromark.com/20-piece-Micro-Size-Drill-Bit-Set-with-Index-61-80

Dremel bits come down to 1/32"
https://www.ebay.com/itm/120898627737

 

[Walt Barney]

I have a numbered drill bit set that I have had for about 20 years and still use it, I think I won it at a drawing at a tool showing,
that I won two prizes.
Thanks
Walt Barney

 

[ACTION JACKSON]

I have the big ring fitting over the header tube on my gold head CMb and it works very well

 

[Kez]

Guys, thanks for the jeweler drill bit info. I remember having used them many years ago for drilling holes in PC boards.

Steve, can you post a picture of the big ring that fits over the header of your CMB?

Thanks, k

 

[Tom Foley]

Kes , send it to me and I'll put a few dabs on there for you . Should last for years . Check the sizes on AN washers and you night find one close that you could work MSC or McMaster has anything you need . A set of Jobber size # drills is priceless around the shop .

 

[Kez]

Hi Tom,
Thanks very much for your offer. I wish I read your reply last night. I ended up gluing a piece of 1/16 K&S tubing with JB Weld. The ID is just big enough to accept the spring.
I am going to try it and see how it holds up. If it did not work, I will send the header to you.
Thanks again. kez

 

[Tom Foley]

Hi Tom,
Thanks very much for your offer. I wish I read your reply last night. I ended up gluing a piece of 1/16 K&S tubing with JB Weld. The ID is just big enough to accept the spring.
I am going to try it and see how it holds up. If it did not work, I will send the header to you.
Thanks again. kez

That is a good idea !!! Let us know how it works. I like that !

 

[Mark Anderson]

When I drill a header, I do it at 45 degrees right in the corner where the flange meets the body using a .040 drill bit. I have never had one wear out

 

[Mark Anderson]

If you say so Tom. Ran big blocks for years, never a failure. I have headers with many hours on them with no failures. As you said there are alot of variables. Just sharing what works for me. Not trying to debate. If your method works for you great.

 

[Kez]

Hi Mark, can you post a picture so that I can see how you drilled the holes? Do you have to bend the "U" of the spring?
Thanks, k

 

[Tom Foley]

If you say so Tom. Ran big blocks for years, never a failure. I have headers with many hours on them with no failures. As you said there are alot of variables. Just sharing what works for me. Not trying to debate. If your method works for you great.

You know I tried to delete this because it didn't sound right after I read it at a stop light lol . I did not mean to sound disrespectful ! You are right whatever works is good ! Really it's not so much a failure to me but when I see that hole elongating , getting near the edge I just hate that . Now just to get a chance to actually run !!