A fix to stop backfires on the standard end can


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Feb 6, 2003
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My Bikes Seat
If you've got a Y-piece and a standard end can, you'll know all about the backfires that this combination creates. The backfires are reportably fixed by getting a free(er) flowing end can and sealing all the joints with paste.

My pipe is fully sealed with firegum but still backfires, so I decided to experiment with the standard end can. I drilled some holes in it, drilling 1 hole at a time. It took 4 holes before the the backfiring stopped on my bike. I made the holes with a 8mm drill bit.

The only downside is that the bike's now louder - it sounds like an aftermarket end can. I'm not too keen on loud pipes, so I've welded the holes shut and gone back to the backfiring.

If you want a louder engine note but can't justify an end can, try drilling a few holes in the standard jobbie. Do 1 hole at a time, until you get the sound you like. The mod is totally invisible once the cover is put back on.


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Geoff it was an old shed you wanted to experiemnt with and remove all of BMW's designed in features, we should have swapped bikes you (was perfect) ADV for my less than (PD) a fair swap considering I'd have had to suffer servo brakes :D
Geoff, there are times when I do think that you need to get out more mate!

For those of you out there with standard plastic panniers beware the Y piece and standard can combo - I melted a f*****g big hole in my pannier on a blast across France and Spain. No problem with Vern's I would guess though - 'kin bombproof


Yes, I'd be pretty pissed off too if I'd just found out that I could've saved £300 quid on a Remus :dabone
Nope. I did 1 500 miles with the holes there and no problems or signs of them whatsoever. It eliminates backfire pretty well - I just don't like the sound of a noisy exhaust.

The can sounds just like a Remus with these holes drilled into it. I know some folks like the sound of an aftermarket end can and the beauty of this mod, is that you can drill the holes one at a time and listen to the difference to get the exact engine note you like. If like me you don't like it, just seal the holes up again. It's completely flat, so it took me about a minute to weld them up ( disconnect the battery before welding ).
But this is in combination with a Y-piece, right?

I have a spankling 1998 75th anniversary model R1100GS with cat and lambda that will monitor CO2 output. If I'd drill holes in the exhaust, wouldn't the lambda get confused about the 'leaks'?

'Fraid there IS a problem with Vern's and heat. The panniers are totally bombproof, but two issues:
First - the heat from the can is transferred directly through the alloy to the contents. No, the panniers don't melt, but what's inside them does! As I found out when I discovered a plastic bag welded to my t-shirts. Have bought a piece of rigid high temperature resistant insulating material and will be fitting it to the can side of the left box to protect the contents.
Secondly - the 'commodius' nature of the boxes means that there's virtually no airflow over the exhaust. This contributes to the problem above, but also means that all the exhaust gasses are funneled onto your left rear indicator. Mine melted and slowly dribbled off the bike! Only solution is to fit some kind of extension tube to take the gasses out the back. Toutatech include one in one of their pannier kits and apparently will sell it separately. I on the other hand, used a piece of thin walled steel tubing I got on the ferry over to France. Originally the container for a mini football game, it worked over two weeks and 2500 miles.
Great boxes, great bloke, great heat!
Y and standared can

With fitting a Y piece, does this make the can run hotter?, is it worth putting a heat plate on the side of the pannier.
And has anyone tried silicon to seal the joints, I had a stainless system made for a Rc600 Gilera once, they fitted it with only silicon seal, (from B&Q) three years later and it was still spot on.
Yep !

Used a bit of silcon to seal mine, found it did a better job than the gum gum I had ?
still get a odd backfire but its a laugh setting off car alarms......

:D :D
Y piece and hot stuff

Just read Gogols' post re melting panniers.....scary and expensive. I'm off to France/Italy etc in June and am a little concerned as I have the 'Y' piece fitted and will be using standard BM panniers. Was this a one off or have others experienced the same problem?

Looks like I might need to get some silicon then. What type/brand... you guys been usin then? Or will any old kitchen/bathroom silicon do, bound to have some lurking in the garage somewhere!



LOW MODLUES (check spelling)
This is a bit more flexable, slow cure.

I'd also like to know if this is possible on an R1100GS with cat and standard exhaust.
Would love a louder exhaust but SWMBO has sussed the wife pound conversion so I can't fit a Y-piece and Remus at the moment.
Anybody tried it on an 1100GS with the standard system?

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