Pet Peeves - motorcycle related only or this thread will consume the board!

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desert_max

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I don't have awful lot of pet peeves with regard to motorcycles, but I did discover one thing today that bothers me. Take aftermarket exhausts for example. The '90 semi project Vmax that I have has 2 Brothers slip-ons. These are some huge cans. Whoever installed them nicely fashioned a couple of very substantial aluminum bracket/hangers to support the massive mufflers. Hangers that suspend from the shock mount/grab rail area. I intensely dislike that and am of the opinion that if a muffler can't be hung with a bracket that is almost invisible, it shouldn't be on the bike. In this case I will let it slide because I will not be keeping this motorcycle.

IMG_1132.jpg

Then there's the Honda 750 K5 that I just picked up. Gorgeous, pristine Kerker came with it. But, yeah, you guessed it, a steel bracket made to hang off the shock mount was expected to be used to hold this can up. I refuse. I trimmed it back, bent it into shape, and tied it into the rear footpeg mount. This can isn't going anywhere. And you can barely see the mount.

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Sorry, I had to vent. But, I do not like unsightly large brackets that aren't really necessary.

And while I'm at it, as used exhaust systems go, this Kerker is among the nicest I've ever come across.
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Something I like to see to lighten the appearance of unsightly brackets is a series of holes to lighten them visually, weight-wise, you're not making much of a difference, but visually, they definitely become more-bearable. Going graduated hole sizes helps with the cool-factor.

For something you're supporting which is long, the vertical bracket is a better choice than the horizontal bracket. Having said that, I also have used the fabrication of the horizontal bracket on my bikes.

I suggest a fender washer on that rubber washer/grommet to provide you with more bearing area for the rubber. In the fashion you have, it will fail over-time. GB electrical hardware or the Jandorf grommets, available at Ace Hardware or Home Depot, should have grommets that will fit the hole on the Kerker flange, or you can simply use a thick rubber washer, I'd probably use two thinner ones, on either side of that canister flange, 'sandwiching' it and providing more resistance to vibration, and a nylok nut on the inside. Jandorf 17/32 in. Dia. Rubber Grommet 5 pk - Ace Hardware The wider wall ones look to be much-more supportive. If you're just doing wide rubber washers instead of a grommet, I'd use a SS fender washer about the same size as the rubber washer, then the rubber washer, then the canister flange, another rubber washer, and another SS fender washer nestling-against the bracket. Making the bracket parallel to the canister flange, rather than at some oblique angle where the rubber washer is 'pinched' at one side, is much better for survival of the system of attachment. A slight bent-in 'dogleg' could get things parallel, or a stack of SS fender washers (my least-favorite) to accomplish the parallel-geometry between the Kerker canister flange bracket and your hanger-strap.

VMax desert-max Kerker 4-1 strap.pngRubber grommet.png

Congratulations on the SOHC 750/4, it is much-cleaner than the one I have. I also have the Kerker 4/1, but it's rusty.
 
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I'm willing to bet those Two Brothers cans aren't as heavy as they look but I agree with you, that bracket is horrible.
 
when I've made horizontal brackets to hold exhaust weight I add a 'side' extension to the leading edge to go under something like the frame or footrest hanger so if the bolts get loosened the bracket will still stay in place
 
The original bracket could be "hidden" by painting it black, similar to what has been done to "reshape" this Honda petrol tank.
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Now I understand why you want to get rid of that hanger to hide it but as FM said, a horizontal bracket is not the best enginerring solution due to the moment at the mounting.

Although the exhaust can may not be particullary heavy, without any support and the far end, there will be more stress towards near to where it is mounted, namely at the engine, that may cause the metal to fracture.

My suggestions would be to add another piece to triangulate the bracket to stop side to side movement, the orange strip in the photo. If you do not have a welder, use a bolt (yelow circle) to hold it to the other piece. This also doubles the amount of material at mounting point. Ideally there should be a bracket as vertical as poosible, like the green line but then we're back to the original problem.

To give some vertical support, extend the bracket and bend it under the frame, as per blue line - I believe this is what JT is saying.

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Thanks for the commentary, guys. As it is, it seems fairly well-planted and solid - unless it loosens up. I do like the triangulated suggestion (02GF74) or that AND what JT has suggested.

...and then there's Mr. FM:
I suggest a fender washer on that rubber washer/grommet to provide you with more bearing area for the rubber.

Yeah, the original Kerker grommet was pretty wasted. That was all I had on hand. When it curled like that (without a washer) I pulled it immediately - but not before snapping a couple of photos of the faux paux. I'm not sure it's needed, again likely to prevent metal fatigue on the bracket, but I will source something that won't be unsightly.
IMG_1408.jpg

And after cutting to size, I did fashion bends on both ends of the bracket to mount flush with the respective surfaces. (Still haven't re-painted, but it's a good fit.

K5 Bracket.JPG

Once again, I appreciate the interest and suggestions. I'm keenly aware this isn't a Vmax, but IS one of my favorites from "back in the day" - along with the fabled Yamaha.
 
If you added a cross-piece at the point where the longer, extended bracket runs-up under the peg-hanger tubing, you could use a U-clamp there to secure the bracket. That would look much-better than a hose clamp, if you merely 'cupped' the steel bracket to the tubing contour and then added a perforated hose-clamp.
 
If you added a cross-piece at the point where the longer, extended bracket runs-up under the peg-hanger tubing, you could use a U-clamp there to secure the bracket. That would look much-better than a hose clamp, if you merely 'cupped' the steel bracket to the tubing contour and then added a perforated hose-clamp.

Pardon the crude rendering, but are you suggesting a bracket supporting the pipe from underneath (out of sight, mostly, out of mind)?
IMG_1408Highlighted.jpg
 
The bracket 02GF74 shows with his blue line, is the placement of which I was speaking. It would be simplest to just continue the bracket past its current point of attachment, and have it running vertically on-edge along the base of the triangle, towards the front of the bike. Then you could use U-bolts to fasten the strap to the tubing. That would probably be somewhat bulky in appearance, which is why I think changing the orientation of the bracket, to running its flat-side parallel to the ground after the bolt-hole for the forward megaphone support, and U-bolts over the tubing, and through the bracket strap.

A compromise could be, run the strap past the point of attachment to the triangle in a vertical orientation, and them weld a piece to T the bracket, to run under the tubing, so that again, a U-bolt could fasten the bracket to the base of the triangle tubing. That would be pretty-much as 02GF74 showed it.

I'm not any-good at design software, or I'd sketch something up.

Honda 750-4 megaphone hanger.01.png
 
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I see. Variations on a theme. Well, thanks for all the input on this. I will stabilize it eventually, but for now, there are other items higher on the priority list for this thing.

Thanks again!
 
Re. Rubber grommet, most exhaust systems (car and motorcycle) move relative to the bodywork or frame so are attached using rubber doughnuts or bobbins.

You would need a rubber buffer/bobbin/grommet between your bracket a d exhaust hanger to dampen out vibrations. Use a nyloc, or metal nyloc or spring washer so the bolt does not undo.
Screenshot_20210616-201159.jpg
 
That's a darn good reminder. While an SOHC 4 doesn't torque like a 383 stroker, it does need that flex ability. Hmm, Then a flat rubber washer won't allow that (even though the bolt is smaller than the hole).

Sheesh. Well, I'll figure something out. Thanks.
 
I'm over thinking this.
A rubber grommet should be enough; spring washer won't work as the bolt would be too tight.

Use an aerotight nut,* tighten until just all play is gone so any tiny movement between hanger and bracket is dampened by the rubber.

* could use nyloc if you are sure the insert won't melt.

Screenshot_20210616-224750.jpg
 
You know, I've been thinking about this a bit more myself, and I can't think of a single motorcycle in my garage that has rubber isolated exhaust system - either originally or now. Frankly, I'm not sure it's really even necessary. At the very least, risk is very low. With solid motor mounts, the powerplant (and exhaust tubes) are planted. Then, we're really only talking about vibration.

...I wonder if HD pipes are rubber isolated
 
You know, I've been thinking about this a bit more myself, and I can't think of a single motorcycle in my garage that has rubber isolated exhaust system - either originally or now. Frankly, I'm not sure it's really even necessary. At the very least, risk is very low. With solid motor mounts, the powerplant (and exhaust tubes) are planted. Then, we're really only talking about vibration.

...I wonder if HD pipes are rubber isolated
On the HD models with the rubber mounted engines, the exhaust is rubber mounted. My Fatboy Evolution is not rubber mounted - the exhaust is solid mounted.
 
...and I do like that Aerotight nut. Looks expensive.
Working on H-1N helicopters, many of the nuts were locking nuts with four slots instead of the two as pictured. No Nylocks allowed. I still have a jar of miscellaneous sizes around, but all are in SAE and National Fine thread. The other style of nuts were flanged with griping ridges on the face of the flange. We used nuts drilled for 0.032" stainless safety wire. Those are my favorite - I have the twist pliers and both 0.032" and 0.020" wire rolls.
 
I was trying to find a picture of one that I had made but this is the best I could find, it is made of 6mm stainless steel and is fixed by a bolt at the rear of the foot rest hanger but it passes on forward with a 3mm piece of plate welded to the lower side so that it fits snug against the bottom of the footrest hanger and is hard to see, the brake lever hides it also, even with loose bolts it didn't drop

streetfighter 3.jpg
 

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