Installing exhaust pipes/muffler...

[bobdo]

Thanks Chris,
Ok, so a '46 EL & FL should have the mount above the sidecar loop casting. It appears to me that the pipe clamp is a "C" shape, but not certain. From my research, approximately an equal amount of bikes highly restored & original condition have the clamps above & below the casting on 1947 EL & FL models.
As a Senior Judge, what's your take on this? I'm not having my bike judged, but I't seems to be a detail that varies in placement & type of clamp.
Once again, I appreciate all the help you give. -Bob

[Steve Little]

Here is a factory shot of the 1947 UL.

Chris. It may be my small Ipad screen or lack of reading glasses, can you look at the original picture and let me know you'r definition of what looks to be non original welding just above the sidecar loop.
Maybe this picture is a experimental 1948 U model (taken early in 1947 during the development stage of the new style frames for 1948)
It looks like the sidecar lug has been cut and shut to assimilate the new new angles for the Wishbone frame.
Regards Steve

[Chris Haynes]

All I can tell you is that the photo was entered into the Pholman archives on June 7 1947.

[bobdo]

I'm back on the exhaust installation.
I have a question, what is the typical depth that a header pipe goes into a Knuckle head? I have a matching set of heads. Both header pipes are close to the same diameter. The rear pipe slides in nicely all the way, about 5/8". The front pipe is very tight & only goes in about 5/16". Is that common? Is 5/16" enough? I'd like to know before I trim length.
Also, It's too early to tell because I'm still fitting the front header pipe, but it looks as though I need to attach the clamp above the sidecar loop casting. I have a NOS "C" shaped pipe clamp & a NOS "b" shaped frame clamp that I'm using. (I know that's probably not right for a 47EL) It appears that if I wanted to attach the clamp below the casting I would need both "b" shaped clamps due to the lack of room. -Thanks

[55tmm]

Here is a pic of the clamp on my original 47 FL ,don't think its ever been apart.
Hope it helps

[bobdo]

55tmm,
Thanks, that is a new configuration to me. It appears both brackets are "b" shaped & back to back. I still wonder if the location under the casting was only for slinky allowance or all the time. The two "b" shaped brackets are whats available aftermarket, so maybe they got it right. I've only seen these mounted above the casting. I've seen many many NOS brackets that are a combination "b"frame & "C"pipe. I bought a set. I've never seen this combination on a bike though, its either one type or the other.

[bobdo]

Hey everybody,
I finally got the front header bracket on, here's what I did. DISCLAIMER: this is not meant as final correct information toward a 100 point restoration. I'm not having my bike judged. I wasn't able to get definite OEM bracket mounting info for a '47 EL. I tried a couple ways, but this is the only way I could get it to fit. The bracket is repop, but is exactly like NOS. I have both & used the repop because I had to elongate one of the frame bracket holes slightly to align. (see pic)
Also, (see pic 2) a rookie mistake. While fitting the exhaust I aligned the front muffler clamp with the front edge of the muffler pipe. This seemed logical to me to maximize the clamping surface. It always bothered me why nobody did this, I thought they were just getting more length out of the exhaust, now I know. The first kick told me why when I planted the kicker arm into the front of the muffler. Luckily, it didn't tear through.
I hope this info helps someone out. If you have questions about mounting a Knuckle exhaust, let me know.