Exhaust noise coming from under the bike

Wow, looks like the underside of a number of my cars over the years.
I know that grey slop - sticks to YOU like mad. At least it washes off with water.
It will last for a few days with tin cans - longer if it remains tighly clamped with no flexing and minimal vibration.
Sometimes, I have had better luck simply taking extra care to trim the tin cans, "just so" and clamping a double layer of them without that grey stuff at all. When it turns to powder and falls out, the space it occupied becomes a hole.
However, if you were happy enough with the original pipes with 25% holes, you will be please with the improvement to only 5-10% holes. Not perfect, but an improvement.

I think you need to make friends with a plumber who is good with steel pipe and fittings. For a couple of beers, you'll get it down to 98% solid, 2% holes and it will last for weeks/months/years :wink2:
 
well it held at least one trip to work :)

man this sounds so much better.. Much deeper, beefier sound but lower volume. Less as if something is wrong with it lol

Less head turning though, more like a 'normal' bike. But I'm happy.
 
I'm thinking about adding some heatwrap around this construction of mine. Just to keep it all in place, so the cans don't come off
 
more research shows that it'll last if I now wrap this fix in glass fiber tape (stuff used in putting up dry wall or something, it's cheap), let it heat up and burn off all the glue which leaves it a caramel color, then spray paint it to further protect the exhaust paste from water (which dissolves the stuff).

That's what the expert rat bikers tell me :laugh: I guess it's worth a shot since it'll only cost me like 3$ for a roll of tape, I still have heat resistant black spray paint lying around
 
So just a quick follow-up

I wrapped the exhaust with the budget fix in that glass fiber tape stuff, and painted it with some heat resistant black paint. I put the fix on a week and a half ago, and then the wrap I did last Thursday (5 days ago), about 5 days in between the two.

Today I noticed my exhaust was getting slightly louder again.. :doh:

I think the exhaust putty stuff has gone, and the cans are the only thing keeping it less loud than it was at this point.

So for anyone out there considering this: it's probably not worth the effort or the money, even though it's a very cheap fix.

Unless if you don't mind fixing your exhaust up every two-three weeks.
 
If you decide to go for one more round before visiting the plumbing supply or the welder who works off the books evenings and weekends, try a double layer of soup can with the seams offset and none of that grey slop. It won't be perfect, but if you are careful with your trimming and get a pretty tight overlapping fit, it will stay without changing longer.
That grey stuff turns to powder and then when it falls out, the spaces it used to occupy become large holes and the metal loosens up.
 
thanks Lou, I think that will be my next move. Also I will get more hose clamps, since those seem to hold everything together quite well actually

the grey slop is terrible and I don't recommend anyone ever using it. This is 100% made for *sshole used car salesmen to hold leaks for a few days so they can make the sale, only for the buyer to find out the exhaust is busted a few days later. I'm thinking even duct tape will do a better job to be honest
 
Willem, could you try wrapping it in a couple layers of that fiberglass tape, and coating it in the high heat JB weld ?

Depending on the size of the leaks i would assume the tape would create a base and the JB weld would coat everything then harden and bond through the tape to the exhaust and create a seal.

I have never done this so who know if it works lol
 
I've wanted to try that myself on my old car.
Another thing I read somewhere is to use the high heat permatex silicone under a tin can - but I have no idea if it would last any longer before burning off. As I recall though, the temperature ratings are about the same - so maybe...
 
Hmm I can't seem to get a hold of high temp JB weld (or any JB weld for that matter) in the Netherlands. Well, not without selling my left leg and shipping some from the states at least. And I need my left foot to operate the shifter peg unfortunately.

The only thing I can really get here in NL is 'moldable steel', some kind of putty. Gets as hard as steel, but it can't withstand the heat. The only thing that says it can is this exhaust paste. But then that can withstand heat, but not water.

I'm thinking I'll take all the crap I put on there off, leave the paste and try to shape some cans or other material in such a way that it closes most of the gaps. I'll strap it all down with some hose clamps and wrap it in a layer or two of glass fiber tape, then I'll smear on some goo for good measure, and add some more layers of tape. I read it did work for some people who had small holes in their exhausts, so I'm thinking the bigger the contact surface the better (which I'll have a lot of with the exhaust wrap.
 
same issue: can't get it here without paying at least triple the price of the product for the shipping alone, and that's already through some dodgy ebay seller then. I'll try to find something similar but european-made.
 
If it were me I would remove the crossover pipes all together.Then gets a piece of metal tubing thats larger and cut a piece of and have it welded as a patch.Seems like the perminant salution other wise you will have to keep rewrapping or patching
 
yea I think if the next patching/rewrapping session doesn't last, I'll get the front H-pipe cut off and the resulting holes welded shut. The rest of my exhaust is in great shape, even the other H-pipe is 100% solid.
 
If you wasnt so far away I could help,I have an hpipe assembly that used to be on my bike Im never going to use.I think shipping from the states over to the netherlands would be quite expensive.
Another thing that might work is if you can get some high heat muffler wrap?
 
Last edited:
Digging up this thread again :)

About a month and a half after my budget exhaust fix now, and it's a complete mess again. Running lean, lots of noise (more than it ever has been, probably since the holes got a lot bigger when I removed the loose-ish rust with the wire brush during the last fix) and it's getting harder to start the bike even. She still runs alright though, but I need to address this issue. Not just for me, but I recently moved to a new place (2 minutes walk from the beach: lovin it) and I want to keep the neighbors happy.

So I'm thinking no more grey slop. If I find some time (and it's not raining) I'll go fix it up again.

I'll let you guys know what I find, and if it'll last :)
 

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