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AnonymousA little while back I drove over my pride and joy FMF Powercore4 muffler. It was damaged beyond repair. I sulked around for a few weeks, then gave myself a good kick up the arse and told myself to get over it.
I had an old Ducati muffler which I got out of a dumpster at the local Ducati dealers. I also had an original stainless steel muffler and mid pipe. With a bit of cutting and grinding, I was able to mate the mid pipe from the original to the Ducati muffler inlet. I made a small collar to match up the difference between the two size pipes and used some thin copper sheet to make it a really tight fit. I dicked around for couple of days making sure that I had all the angles and clearances spot on. It was critical that the tyre wouldn’t hit the muffler on full compression of the suspension. ie after landing a double backflip etc.
I marked the joins of the pipes and muffler with permanent marker, so it was simply a matter of lining up the marks and welding the two seams. Initially I was gonna get it welded with a stainless TIG or MIG, but out of curiosity I popped into a muffler shop and asked them if the did stainless welding and how much. The guy told me they normally just use normal MIG on stainless systems and had never had a problem. Taking away this free tip, I dropped over to a mechanic mates workshop and borrowed his MIG. I lined up everything and gave it a small tack weld. It was slightly out, so I broke the weld so I could do it again. In the process I burnt my hand on the pipe and dropped the muffler. When I picked it up and lined up the marks again, I had somehow rotated the muffler input pipe and mid pipe by about 20-30 degrees. My alignment marks were only on the muffler and input pipe, as the other end was a snug fit. I didn’t notice the problem until after I had got home and placed it on the bike.
I thought about cutting the mid pipe and re-welding it, but I found that when I mounted it on the bike, the clearances were all still good but the muffler looks a bit funny as it is not mounted vertically. If I find at a later date that it causes issues, I can always redo it. I reworked the original Ducation mounting bracket to suit the mounting position on the WR. The muffler had some captive nuts in it, so I utilised those, rather than drill holes in the can.
One day if I get bored, I might clean up the welds with a linishing disk, but at this stage, I just want it on the bike, so I can get out and do some riding when I am healthy enough.
Here are some pics of the finished product. Unforunately I never got any of the beginning of the project, as the finished product doesn’t do justice to the amount of work that went into getting it right.
EDIT: I forgot to mention That I fired up the bike and it sounds awesome. I reluctantly say that it even sounds better than the FMF muffler did. It is a nice deep thump and not that loud. The total cost of this, including parts was absolutely nothing. It was all done with bits and pieces I scrounged.
1)The joints. The orange discolouration isn’t rust, I think it the flux from the MIG
2)Looking from the front of the muffler, you can see how the rotation is offset from verticle
3)The following two pics are from the rear, showing the offset.
4)The mounting bracket. Don’t know how well this shows it
5)Mounted with side cover in place, but no seat.
Nice job Nigel
I told you, you had to much time on your hands :laugh: Question When you migged up the pipe,did you use stainless steel wire ? If you didnt it may fracture down the track a bit as the weld may be brittle.(trust me,I know)I also dont mean to put a damper on your efforts but you really need to cut and rotate the pipe to make it look proffessional. Ps in future wear gloves and you wont burn yourself.(thats the workshop supervisor in me coming out!:laugh: I do the same thing at home myself:laugh: ) Whats your next project??cheers Ollie
AnonymousThe MIG was just plain wire as that’s what the muffler guy said he used on stainless systems. I always thought you needed to use stainless filler on stainless steel, but I was surprised as to how easily it actually welded with the standard MIG wire.
As far as rotating it, I will keep it as is at the moment. It will be a talking point when people see it. I’ll come up with some bullshit about optimal exhaust flow theory and the dyno testing proved that this was the best angle for the muffler. When the weld cracks, that will be the motivation to change it.
I will no doubt one day rotate it, as I am deep down annoyed with myself with such a silly mistake, considering how much time I spent playing around to get all the angles correct. It was like being back at school doing three dimensional spacial calculations.
The next project will be a for a poor man’s motard setup , using a set of 48mm forks (if I can negotiate a deal to get them) and some Avon Distanzia tyres on trailbike rims. Obviously because of the relative high cost involved with this dream, it will take some time to raise the funds, but it gives me plenty of time for my overactive gigantic brain to do some lateral and creative thinking.
N
AnonymousTrailboss wrote:
Quote:PS thought you ran a trials tyre?TB
I normally do, but I currently have a 19″ YZ wheel mounted with Maxxis IT tyre. This is because of my runs around the streets to adjust the carby jetting. The trials tyre would get destroyed if it ran on asphalt, as it is so soft.
I also have another 18″ rear with a paddle tyre mounted. It’s nice to have a choice.
AnonymousTrailboss wrote:
Quote:Just noticed the side cover, whats doing there Nigel? Your going well today with how to win friendsTB
That was David Knight’s doing, not mine.(as described in point 6 of original post) Honest mister:dry:
You know where the “smite” button is. My karma is too high anyway.
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