Plugging muffler crossovers

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desertrefugee
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Plugging muffler crossovers

Post #1 by desertrefugee » Fri Sep 06, 2019 4:18 pm

Hey guys, I was lucky enough to find some early Sportster mufflers for my 78 GL. They were non catalytic and non crossover. Easy breezy. But they are getting scarce and I find that most of those now available cheaply have the crossover holes that need to be plugged. What are some of the more ingenious ideas folks have used to plug those things? Freeze plugs? Welding required?
'97 Valkyrie, '79 CBX-Z, '78 GL1000

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Sidecar Bob
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Re: Plugging muffler crossovers

Post #2 by Sidecar Bob » Sat Sep 07, 2019 7:50 am

Here's what I did for the ones on my winter machine
Blocking crossover.JPG
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Mr. Honda ('83 GL1100/Dnepr) summer New Engine Thread
The Famous Eccles ('84 CX650EI/VeloUral) winter Never Ending Build (CX500forum)
Click: Colour schematics for all GL1000 & GL1100 and GL1200 standard models plus instructions on how to download the full size version
"A guy with two sidecars can't be all bad." - Cookie
Another guy with two sidecars..... Hmmmm... must be something to that....

heraldhamster
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Re: Plugging muffler crossovers

Post #3 by heraldhamster » Wed Sep 11, 2019 3:14 pm

I've even gone so far as to just cut 'em & then pinch them off very tightly.
seems to have worked well, but that was on FLH mufflers, I think.
sorta bulldogged custom 1978 GL1000 - "geekster" - daily rider
full Vetter dress 1979 GL1000 - "Barge" - daily rider (currently down)
1986 1200 Aspencade - "Heart of Gold"
1990 1500 Aspencade - It's ALIVE! but with a green drool...
1978 for $100 - project in worx
1978 from a previous member here - taking up space
my original '79 bought in '91 - replacing engine (eventually, maybe someday)

H2G2=42

A competent and self-confident person is incapable of jealousy in anything. Jealousy is invariably a symptom of neurotic insecurity. ~ Robert A. Heinlein

The good thing about science is that it's true whether or not you believe in it. ~ Neil deGrasse Tyson

SnoBrdr
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Re: Plugging muffler crossovers

Post #4 by SnoBrdr » Thu Sep 12, 2019 1:22 pm

Sidecar Bob wrote:Here's what I did for the ones on my winter machine
Blocking crossover.JPG


Won't the plugs melt?

The ones I used didn't have a crossover hole, I was lucky I guess.
78 GL1000 Original Owner 131k

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Sidecar Bob
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Re: Plugging muffler crossovers

Post #5 by Sidecar Bob » Thu Sep 12, 2019 2:19 pm

The plugs are steel fender washers. The smaller outer ones are a good fit in the openings and the larger inner ones had to have the edges bent so they would fit inside the tube. The black around the edge is high temp silicone and they are held in with 1/4" bolts with ESNs. It has been together since fall of 2016 (almost 6200 Km) and shows no sign of coming loose.
Mr. Honda ('83 GL1100/Dnepr) summer New Engine Thread
The Famous Eccles ('84 CX650EI/VeloUral) winter Never Ending Build (CX500forum)
Click: Colour schematics for all GL1000 & GL1100 and GL1200 standard models plus instructions on how to download the full size version
"A guy with two sidecars can't be all bad." - Cookie
Another guy with two sidecars..... Hmmmm... must be something to that....

SnoBrdr
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Re: Plugging muffler crossovers

Post #6 by SnoBrdr » Thu Sep 12, 2019 2:28 pm

Sidecar Bob wrote:The plugs are steel fender washers. The smaller outer ones are a good fit in the openings and the larger inner ones had to have the edges bent so they would fit inside the tube. The black around the edge is high temp silicone and they are held in with 1/4" bolts with ESNs. It has been together since fall of 2016 (almost 6200 Km) and shows no sign of coming loose.


Ak OK thought it was a simple freeze plug.
78 GL1000 Original Owner 131k

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Sidecar Bob
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Re: Plugging muffler crossovers

Post #7 by Sidecar Bob » Thu Sep 12, 2019 3:04 pm

You could use a steel freeze plug if you could find the right size but I had the washers &c on hand. This is the first set of HD mufflers I've had with the crossover; It wouldn't be my first choice but they were free....
Mr. Honda ('83 GL1100/Dnepr) summer New Engine Thread
The Famous Eccles ('84 CX650EI/VeloUral) winter Never Ending Build (CX500forum)
Click: Colour schematics for all GL1000 & GL1100 and GL1200 standard models plus instructions on how to download the full size version
"A guy with two sidecars can't be all bad." - Cookie
Another guy with two sidecars..... Hmmmm... must be something to that....

heraldhamster
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Re: Plugging muffler crossovers

Post #8 by heraldhamster » Fri Sep 13, 2019 12:35 pm

Sidecar Bob wrote:...It wouldn't be my first choice but they were free....


right?
nice ingenuity on the fab work.
sorta bulldogged custom 1978 GL1000 - "geekster" - daily rider
full Vetter dress 1979 GL1000 - "Barge" - daily rider (currently down)
1986 1200 Aspencade - "Heart of Gold"
1990 1500 Aspencade - It's ALIVE! but with a green drool...
1978 for $100 - project in worx
1978 from a previous member here - taking up space
my original '79 bought in '91 - replacing engine (eventually, maybe someday)

H2G2=42

A competent and self-confident person is incapable of jealousy in anything. Jealousy is invariably a symptom of neurotic insecurity. ~ Robert A. Heinlein

The good thing about science is that it's true whether or not you believe in it. ~ Neil deGrasse Tyson

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Sidecar Bob
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Re: Plugging muffler crossovers

Post #9 by Sidecar Bob » Fri Sep 13, 2019 12:57 pm

Thanks. Here's what they looked like on the bike when I put that exhaust system together. Unfortunately I made the mistake of buying new reproduction headers from Silver's instead of having a friend on cx500forum send me a used set and they were almost completely covered with rust after the first winter. I now have a set of original GL500 headers waiting for those ones to rust out (they are fairly rough but I'd bet they'll look a lot better in 7 or 8 years than these do after 3).
Eccles 25 Nov 2016 left.jpg
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Mr. Honda ('83 GL1100/Dnepr) summer New Engine Thread
The Famous Eccles ('84 CX650EI/VeloUral) winter Never Ending Build (CX500forum)
Click: Colour schematics for all GL1000 & GL1100 and GL1200 standard models plus instructions on how to download the full size version
"A guy with two sidecars can't be all bad." - Cookie
Another guy with two sidecars..... Hmmmm... must be something to that....

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ericheath
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Re: Plugging muffler crossovers

Post #10 by ericheath » Sun Sep 15, 2019 5:41 pm

I used freeze plugs. Tapped in until snug and tack welded to keep them there. Works fine. Wish I could get the center Blick back in but I welded mine to the headers. I can’t stand the loudness. Some Loud sounding bikes are pretty cool, but in my opinion, the Goldwings are not.

This year I bought some copper pipe caps, spread the ends a bit and drove them in to the center. The sound was so much better, but they only went 20-40 miles before pressure drove them out. I probably could pin them in place. Hmmmm
Whatever I suggest here should be given ample time for a moderator to delicately correct. I apologize in advance.
77 WING, 1200 engine with 77 heads, cams, gl1100 foot pegs, Magna V65 front end, 764A carbs, [-gone Suzuki M109 monoshock--, replaced with gl1100 shocks] gl 1200 swing arm, gl1500 final drive, wheel and rear brakes Valkyrie seat, Meanstreak tank, Sportster pipes, Power Arc ignition off crank.
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Sidecar Bob
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Re: Plugging muffler crossovers

Post #11 by Sidecar Bob » Sun Sep 15, 2019 8:21 pm

You could always try a lollipop baffle.

FWIW, I've had HD mufflers on Mr.H for 22 years and they aren't what I would call loud. Louder than stock maybe but once I'm doing more than about 65 Km/h I can't hear them over the wind noise.
Mr. Honda ('83 GL1100/Dnepr) summer New Engine Thread
The Famous Eccles ('84 CX650EI/VeloUral) winter Never Ending Build (CX500forum)
Click: Colour schematics for all GL1000 & GL1100 and GL1200 standard models plus instructions on how to download the full size version
"A guy with two sidecars can't be all bad." - Cookie
Another guy with two sidecars..... Hmmmm... must be something to that....


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