Sacrificial Exhaust Hanger Build

[Samm]

Hi Folks,

 

After a couple drops the exhaust is inching closer and closer to the swingarm. I don’t plan on becoming a better rider fast enough to solve this problem so here’s my mechanical fix (yet to test…).

 

 

Like an aluminum derailleur hanger on a mountain bike this will bend/re-bend/break before the steel frame mount and can be easily and cheaply replaced (always have a spare and carry with your tools!). This is the stock exhaust but it would work for aftermarket as well.

Tools needed:

Allen Keys – 4mm, 6mm, 8mm

14mm wrench

Drill bits, taps (maybe), bandsaw/hacksaw, file, sander

Hammer and starter punch

 

Materials:

2” x 3/16” Aluminum Flat Bar

Rivets 

JB Weld (maybe)

 

First, remove your can. 6mm allen key for the pipe clamp, 8mm allen key and 14mm wrench for the frame hanger bolt. Drill the head off the "strap" rivet and slide that sucker off.

 

 

You can't remove the rivet completely unless you drill the hole out bigger, it's sandwiched between two layers of the can. You can push it to the side and install a new rivet to cover the hole or just drop a blob of JB Weld on (sand/clean area first). That's what I did. It's hidden on the wheel side of the can and hopefully the JB can handle the heat, we'll see.

 

 

Next, layout the strap mounting holes on your flat bar. I use a hammer and starter punch before drilling holes. I drilled the two small holes with a 13/64" drill bit and tapped with an M6 x 1.0 tap (welcome to Canada eh, a cultural melting pot where all standards of measurement are accepted). By tapping I can use the existing bolts, if that's not in your wheelhouse find some longer nuts and bolts and through-bolt it! For the large hole any old nut and bolt you've got lying around will do the trick. I found an old M8 to keep things metric.

 

 

With the strap mounted to your newly drilled and tapped flat bar hold them up to the frame mount on the bike and decide how far apart you want your mounting bolts. I ended up with 2 7/8" center-to-center but you do you. I thought the distance looked long enough to allow for some bending if dropped but not so much that I was stressing the bracket under the weight of the pipe (as I mentioned earlier I haven't tested this yet...). Mark and punch your new mounting hole and clean up the design. I cut my bracket using a bandsaw and finished with a belt sander but a hacksaw, file, and some sand paper would do the trick. 

 

 

Remember, you need two right off the bat - one installed and one on hand to get you home when the first one breaks after too many falls. 

 

 

 

Its not super pretty but as long as I stick to the same hole spacing I can work on the design as I replace them. Mount everything to check fit then mark a hole for the new strap rivet. You can skip this step if you're still prototyping but I went ahead and committed. You can see the JB in the original hole below.

 

 

 

If you're set on your new strap position, drill for a new rivet. There are two layers to the can. I drilled just through the first and used a washer to achieve the proper spacing so the rivet didn't bottom out. I see no problem with drilling through both layers and using a longer rivet but maybe increased exposure to fumes/heat will shorten the lifespan of the rivet, who knows, I'm not a doctor...

 

 

 

I've decided to repaint the can with some high heat enamel so I'm not setting the rivet just yet - as is it looks like s%#t with the old rub marks. I'll report back once that's done and give an update as to how the new bracket holds up. If anyone else has tried this or if any engineers out there have some tips I'd love to hear from you!

 

Happy Trails Folks!

 

Edited October 17, 2020 by Samm

[Samm]

Painted and assembled!

 

Edited October 18, 2020 by Samm

[CoreCass]

looks nice and sturdy. tough why would you reposition the bracket ?

also. your bracket spacer is tightend with 1 bold. do you have a bump or something to keep it from rotating on the mount of the bike ?

 

[edit i might be stopid. if so than just say so]

Edited October 18, 2020 by CoreCass
[]

[Samm]

9 minutes ago, CoreCass said:

looks nice and sturdy. tough why would you reposition the bracket ?

also. your bracket spacer is tightend with 1 bold. do you have a bump or something to keep it from rotating on the mount of the bike ?

 

[edit i might be stopid. if so than just say so]

No bump. The three bolts on the exhaust strap end of the bracket should keep it from sagging or rotating around the single bolt on the frame end...hopefully. 

 

I'm a little confused with your first question. I slid the strap towards the back of the exhaust to make room for the new sacrificial aluminum bracket.

[Matth]

Yep i get it. Your bracket being weaker than original and will bend before the hanger does hence being sacrificing. Looks a good job.

still needs exhaust lifting though!

[CoreCass]

On 10/19/2020 at 1:18 AM, Samm said:

I'm a little confused with your first question. I slid the strap towards the back of the exhaust to make room for the new sacrificial aluminum bracket.

 

On 10/19/2020 at 8:45 AM, Matth said:

Yep i get it. Your bracket being weaker than original and will bend before the hanger does hence being sacrificing. Looks a good job.

still needs exhaust lifting though!

 thanks for explaining. could not find the right words i guess.

 

might add that i find it more sturdy looking with the bracket a little backward's.  also think its more beautiful in a way. might do this mod as well. [as for 8m..  its not a problem over here across the pond :P]

[Xtz76]

Hi, looks really good.  Have you had any experiences with it yet? Does it work the way you want? Is it tight enough? No wobble more than before? And the most important question: does it bend so it protects the original exhaust hanger? Thanks

[Samm]

25 minutes ago, Xtz76 said:

Hi, looks really good.  Have you had any experiences with it yet? Does it work the way you want? Is it tight enough? No wobble more than before? And the most important question: does it bend so it protects the original exhaust hanger? Thanks

I fortunately haven’t dropped it yet so I can’t say that it works as intended yet but it’s holding up fine to the 1000ish km of on and off-road riding so far. As soon as I dump it on the right side I’ll post the results. 

[Xtz76]

Thanks for the answer. Let's hope your T7 doesn't fall over that often. I'll build that now too. I bought a used exhaust very cheaply. this will now be my subject. Thanks for the great idea.

[Samm]

52 minutes ago, Xtz76 said:

Thanks for the answer. Let's hope your T7 doesn't fall over that often. I'll build that now too. I bought a used exhaust very cheaply. this will now be my subject. Thanks for the great idea.

Good luck! Post some pics when you’ve got it finished, be cool to see any improvements you might make on the original basic design. 

[Samm]

UPDATE:

Okay so this first attempt was a total failure! 
 

I went down hard on the right side on some ice and the thin steel mount bent in and cracked on the sides (as has happened to a few guys already). The 3/16” aluminum is still straight as an arrow - way too strong obviously.

 

I’ll weld the steel hanger and put some relief cuts in the aluminum plate and hopefully the next time She goes down we’ll see a bent aluminium plate. Fingers crossed...

 

[T-88-]

Thanks for the update mate... Keep us posted. I'm keen to find a solution for this issue. I've done a number on my swingarm already :( 

[Matth]

Thats a shame. I think there is inly one way to solve this and do what Cory has done and move the silencer out of the way and redirect the connection tube

[Samm]

I put two relief cuts in the plate about 1/2 depth which still didn’t help - dumped her in the mud and bent the steel again. Might remove some more material from the aluminum next time I have it apart to weld the steel a little prettier. 
 

I agree, the Camel route is looking real appealing. Just can’t justify the cost until I’ve bent and rewelded the original mount enough times that it starts looking like s#%t...then I’ll pull the trigger on a high mount system.

[Boondocker]

2 hours ago, Samm said:

I put two relief cuts in the plate about 1/2 depth which still didn’t help - dumped her in the mud and bent the steel again. Might remove some more material from the aluminum next time I have it apart to weld the steel a little prettier. 
 

I agree, the Camel route is looking real appealing. Just can’t justify the cost until I’ve bent and rewelded the original mount enough times that it starts looking like s#%t...then I’ll pull the trigger on a high mount system.

 

Kudos for trying to address this problem waiting to happen. Since I'm in the market for a tail rack, I'm looking for a bar mounting system that that would stick out just enough to do for the muffler what engine guards do for the engine/fairings. In the meantime, I'll try to only drop my bike on the left side. Doh!

[Boondocker]

On 4/11/2021 at 2:37 PM, Samm said:

I agree, the Camel route is looking real appealing. Just can’t justify the cost until I’ve bent and rewelded the original mount enough times that it starts looking like s#%t...then I’ll pull the trigger on a high mount system.

@Samm  -  The more I look at the OEM exhaust mounting and consider the ramifications of a right-side tip over, the more I want to address it. I'm not ready to buy stick-way-out panier racks or replace a brand new exhaust either, so I think your idea has enough merit explore further.  I was thinking about automotive exhaust hangers made of rubber or a thick woven strap and wonder if something like that could be employed here instead of metal to provide enough flexibility to reduce the chance of subframe damage. I am concerned that a flexible mount may introduce unwanted flex that could fatigue the exhaust elsewhere. Also concerned that the "lateral" remount using a flexible member may not provide sufficient support (might droop). Such are the challenges of trying to jury-rig a modification. 

 

The kind of parts I have in mind

metal and rubber mount

rubber mounts

 

 

I wonder how the Yamaha engineers arrived at the OEM design. Did they never drop the bike in testing?

Edited April 16, 2021 by Boondocker
added links to parts

[Mikebike]

Hi Saam,   

 

     I like your idea, I think I will try it with light gage stainless sheet.  

 

Mike

[Samm]

1 hour ago, Mikebike said:

Hi Saam,   

 

     I like your idea, I think I will try it with light gage stainless sheet.  

 

Mike

Try tinfoil, that frame hanger is weeeeaaak...

 

Just kidding. Good luck, let us know how it turns out! 

[Mikebike]

ha ha thanks,  I dropped my bike yesterday on my second ride, it is a beast I even put the lowering links on it.  I may have to go to the low profile seat .  I dont think I bent the hangers but have not had a good look at it.  

 

[Stujamur]

Any update / progress with this hanger . Looking for a similar mod rather then going the high pipe route 

[Samm]

Fortunately I’ve stopped dropping the bike as much. I’m riding not wrenching for the time being but from my experience this project should be done like @Mikebikementioned above, with a light gauge stainless or maybe 1/16” aluminum. The project doesn’t take long, the materials are cheap, and the stock muffler doesn’t stay pretty for long so I would suggest giving this a try and reporting back with what material you used and how it turned out. 
 

Did you get some positive results @Mikebike?

[Mikebike]

Hey Samm,

 

     I have put this project on hold for now. I am going to get on it once riding season slows down a bit.  Does anyone have a measurement of where the muffler should be so one can track just how much things are moving?

 

[Boondocker]

Following on from the idea of @Samm, the original poster to this thread, I pursued my variant of a flexible hanger.

 

My “solution” doesn’t fix the problem of the exhaust location where an impact that bends it inboard can lead to swingarm and/or subframe damage. My idea offers a little flexibility where maybe bend-not-break would be enough to avoid further damage. There is about 1cm of lateral movement on offer. Note that the exhaust pipe and its connections have to absorb that flex. For $10 in parts and a little drilling and grinding, it’s worth a try.

 

So far, I’ve done one run including a few miles of bouncing through desert washes, no falling over, and it looks to be holding up. I was afraid it might sag because it’s kind of “jointed”. I may replace the rivet between the 2 bolts to tighten that joint in an effort to minimize sagging.

 

This is the link to the part, an automotive exhaust hanger.

metal and rubber mount

 

If you compare the new part to the modified part, you can see what remains after cutting, drilling, and grinding. Second bolt sourced from private stash. Basically, I ground off the rivet that holds the long metal piece to remove it and cut off the "L" bend on the short end.

 

Here it is mounted. As you can see, it moves the exhaust can bracket rearwards exposing any wear that has occurred in the stock position.

 

Close up. A little extra grinding was required to clear the stock beveled washer. I wanted to keep that part.

 

From the inboard side. Note – the exhaust can bracket is riveted to the can. I used a Dremel Tool to grind off the rivet and filled the hole with JB Weld.

 

I guess the acid test will be next time I dump it on the right side and contact the exhaust. Hope I don’t have to report back on that too soon.

 

[glenc0]

like every thing about this mod--cheap and may save the exhaust hanger--instead of jb weld put another rivet in the exhust

[Boondocker]

3 hours ago, glenc0 said:

like every thing about this mod--cheap and may save the exhaust hanger--instead of jb weld put another rivet in the exhust

I don't have a rivet gun but I have JB Weld. It's still holding after a 1000 miles.

 

As an update, I replaced the hanger rivet with a bolt. It hasn't sagged.