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Nice clean look. They compliment the lines of the bike well.
Paul
Thanks. Ultimately, though, Id trim the exit pipes of the cans, so the length is close to the SS100s system. Heres a couple of better perspectives. I didnt trim anything in this interim just-for-fun mock-up, but to my eye the system is a little too elongated as-is vs the SS100, which is more compact...
Yup, Gasbox is getting close to doing a new run of these cans and will hold a pair back from plating for me. This project is therefore green-lighted.
Only question is no dent or with the dentwhich I currently haveas they sell them both ways. I think that I want the mufflers fitted as close as possible to the frame members like I currently have themwhich seems to align well with how the no. 2 cylinders pipe comes back from the port, as seen here. So, Im 99% sure that I will stick with the dented version
Final consideration is whether to invest in a TIG welder. I recently successfully welded up a new kickstand to the 71 Bonnevilles frame using my Hobart MIG, but thats DOM tubing with a wall thickness closer to what Im used to fiddling with: at or just under 1/8. I also successfully repaired the rear mounting stud on the R/H gas tank for this 51 FL (which I think is actually taken from a 61 judging from the badges), and that material is much thinner.
Ive watched the guy at Route 66 Mufflers weld up custom exhausts with a MIG, but I wont have much room for error, as a pair of these mufflers is ~ $200 (unless they give me a break due to no chrome).
Any thoughts? I guess that I could practice with some pipe that Ill have to purchase for the crossovers anyway and see whether Ill be able to do this without ruining the cans
Hmmm I also have to decide whether the crossovers are the same O.D. as the headers. Is it my eyes, or do they look just a little bit smaller than the headers ?
Last edited by NM Pan-shovel; May 19, 2025 at 01:22 PM.
I think the welding jig is easy-peasy: just use 2” angle iron and attach strips of wood to gently but firmly grab the cans and crossovers, so as to put the fishtails in precise alignment in a vertical plane (horizontal on the welding table). Well, maybe use leather or something else softer but heat resistant for the recesses for the cans…?
Regardless, that’d allow me to do the tack welds on one side, then I could just flip it for the other, and repeat the process to complete the welds.
Finally: I found a custom mandrel bending place that might be willing to produce a gentle S-curved extension for me—which if they can add a flare at the forward end would avoid the cost of a TIG welder and bottle of argon for the header. As I’ve said, I don’t think near-perfect inside welds are as important inside a muffler as inside a header pipe.
It would also avoid having to lift the engine to install a new, two-ended squish pipe. The chrome clamps I am using look really nice, so adding one more down by the brake pedal wouldn’t look too bad…
Last edited by NM Pan-shovel; May 19, 2025 at 01:44 PM.
All right… way better. Found a local TIG welder who will do the job for an hour or less labor—his minimum—if I bring it in jigged and cleaned up. So, far cheaper and easier than buying a TIG setup, bottle of argon, and doing all that learning. I would’ve enjoyed it, but that’s a lot of bread for a new SS pensioner!
BTW here is a quick video of the slight change these tips make when added to the Gasbox modifed vintage Sporty mufflers (their baffles are drilled for a bit more flow). Brief break in the storm, so I took advantage. I really like the way they quiet it down just a little bit without losing the neat exhaust note of these mufflers. That slight hiccup sounds like maybe I need to adjust the Super E’s accelerator pump...?
Also: unless I’m imagining things, I think I can see a puff of oil smoke from no. 1 cylinder when I let off the accelerator at a couple of points. Definitely need to R&R that darned front head and get this engine 100% good to go for the next decade or three.
However, I didn’t like the extra length so trimmed the muffler outlets this a.m. I think it looks better with the tips inboard from the tire’s rear edge a bit more as shown below…
After I get the valve stem seal issue ironed out this weekend, and complete the remaining ~150 miles of ring-bedding and change the oil, I will crack open the throttle a bit and see if I want to dremel out those tabs in the fishtails’ outlets. These tips are very sturdy, so I’m not worried about any distortion of the shape, and assume they are there to replicate the British models they are intended for.
Right now—while still being gentle for the first 500 miles—it seems like it’s slightly more responsive just off idle. So, perhaps this particular top end (S&S ported heads w/standard size valves and Super E carb) likes a skosh more back-pressure than the side-by-side shotguns with drilled-out ‘60s Sporty mufflers.
But I’ll be curious to see how the midrange and WOT behavior is. I wouldn’t think that without those tabs there would be much reduction in flow because those tips are 6” tall and plenty wide to meet or exceed the area of the round 1-3/4” pipes…?
Last edited by NM Pan-shovel; May 20, 2025 at 12:32 PM.
I did some quick math and decided I wanted to retain the same area as the muffler outlet, which is 1-3/4 I.D. Well, and I wasnt as crazy about the mid-range effect of those connecting tabs. So, out came the dremel and I removed them.
No sooner had I dunnit, when my neighbor stumbled by and said, Oh, you took out those anti-ringing tabs. Arghhh well, I rode down into ABQ again to get some stuff and complete the 500-mile ring-bedding process, and couldnt hear anything but that wonderful snarling exhaust note. Thank goodness. Looks like I need to get out a flapper disc and remove a touch more material...
However, when I shut off the bike in the relative quiet of the garage, I heard a strange sound sure enough, you can distinctly hear the fuel boiling in the float chamber as the pipes ticked and the oil trickled down into the sump. The valve stem seals get here mańana, so when the carb comes off as part of that process, Im going to experiment by closing off the regular vent into the air cleaner and opening up the aux vent. Might do nothing as some have suggested, but why not try?
This weekend: 500-mile oil & filter change + flush oil tank & lines + no. 1 valve stem seals + check valve seats and lap as necessary.
Yup, Gasbox is getting close to doing a new run of these cans and will hold a pair back from plating for me. This project is therefore green-lighted.
Only question is no dent or with the dentwhich I currently haveas they sell them both ways. I think that I want the mufflers fitted as close as possible to the frame members like I currently have themwhich seems to align well with how the no. 2 cylinders pipe comes back from the port, as seen here. So, Im 99% sure that I will stick with the dented version
Final consideration is whether to invest in a TIG welder. I recently successfully welded up a new kickstand to the 71 Bonnevilles frame using my Hobart MIG, but thats DOM tubing with a wall thickness closer to what Im used to fiddling with: at or just under 1/8. I also successfully repaired the rear mounting stud on the R/H gas tank for this 51 FL (which I think is actually taken from a 61 judging from the badges), and that material is much thinner.
Ive watched the guy at Route 66 Mufflers weld up custom exhausts with a MIG, but I wont have much room for error, as a pair of these mufflers is ~ $200 (unless they give me a break due to no chrome).
Any thoughts? I guess that I could practice with some pipe that Ill have to purchase for the crossovers anyway and see whether Ill be able to do this without ruining the cans
Hmmm I also have to decide whether the crossovers are the same O.D. as the headers. Is it my eyes, or do they look just a little bit smaller than the headers ?
Bit of a side track but just picked this up, used but a very good deal. Wasn't expecting much honestly but very happily surprised, 3-1 mig, tig & arc and it's AC & DC tig with the foot pedal, does 1/4" alone or 3/8" with a spool gun. Mig's better than my Miller Challenger, arc, welds start easier and less splatter, DC tig is better than my degrading eyes and hands can do, aluminium is next when I can find some scrap, all mine 3/4" & up. 8' mig gun will go but love the tig setup come with. For $600 and the guy never used the mig or arc side. Can get rid of 3 machines now, one will pay for this.
Bit of a side track but just picked this up, used but a very good deal. Wasn't expecting much honestly but very happily surprised, 3-1 mig, tig & arc and it's AC & DC tig with the foot pedal, does 1/4" alone or 3/8" with a spool gun. Mig's better than my Miller Challenger, arc, welds start easier and less splatter, DC tig is better than my degrading eyes and hands can do, aluminium is next when I can find some scrap, all mine 3/4" & up. 8' mig gun will go but love the tig setup come with. For $600 and the guy never used the mig or arc side. Can get rid of 3 machines now, one will pay for this.
I will be very interested to hear how you like it going forwardespecially with aluminum and thin-wall steel like exhaust tubing. Id love to have one machine rather than two, and it would be very cool to have TIG on-tap to do various smaller projects.
P.S. - I have a few aluminum scraps, and my neighbor-machinist likely does too, so PM me about what youd like to play with and well see if I can scrape up whatever youd like for cost of cheap postage.
I will be very interested to hear how you like it going forwardespecially with aluminum and thin-wall steel like exhaust tubing. Id love to have one machine rather than two, and it would be very cool to have TIG on-tap to do various smaller projects.
P.S. - I have a few aluminum scraps, and my neighbor-machinist likely does too, so PM me about what youd like to play with and well see if I can scrape up whatever youd like for cost of cheap postage.
Friend is bringing up an old sidecar he's putting on the 66 he just finished, somebody drilled a bunch of small holes, looks like it had a canopy or framed canvas something added at some point, going to do the fill repairs for him. Going to add a set of 18mm sensor bungs for the head pipe on the RK for the SC self tuner kit I scored a while back. Got another head pipe cheap, be the test, I'll do the pictures bit. So far I'm encouraged, still figuring out tungsten types and size and settings. DC inverter tigs have gotten cheap, home shop stuff under $300 new.
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I would’ve enjoyed it, but that’s a lot of bread for a new SS pensioner!
