{"id":380,"date":"2021-11-10T09:00:06","date_gmt":"2021-11-10T09:00:06","guid":{"rendered":"https:\/\/dailybikers.com\/?p=380"},"modified":"2022-11-29T14:39:18","modified_gmt":"2022-11-29T14:39:18","slug":"choosing-an-exhaust-for-a-bmw-r1200gs","status":"publish","type":"post","link":"https:\/\/dailybikers.com\/choosing-exhaust-bmw-r1200gs\/","title":{"rendered":"Choosing An Exhaust For A BMW R1200GS"},"content":{"rendered":"

At first I was pretty happy with the stock pipe on my BMW R1200 GS, but after about 7,000kms I knew it had to go; it just didn\u2019t have the character, or note, that I liked.
\n<\/span><\/p>\n

 <\/p>\n

I<\/span>really wanted that angry twin note, I basically wanted it to sound like my old Multistrada. Thumpy, angry and loud! The\u00a0Multi came secondhand\u00a0with a full Termignoni system and I have to admit it was my favourite note, favourite engine, favourite\u00a0bike\u00a0I have ever owned. Up until last November when I got the GS \ud83d\ude1b<\/p>\n

 <\/p>\n

I still love the Multi and admittedly I cannot WAIT to see\/test\/ride\/hear the new\u00a0Multistrada Enduro X. That should be one hell of a beast that could really go head to head against the BMW GS, maybe even in the dirt. I guess that\u2019s what Ducati are counting on too.<\/p>\n

 <\/p>\n

I have no intention of trading up, or moving on from the GS for four years, at least that is what I have told my broke self, but I do have the winning numbers in the $40 Million lottery next week so one\u00a0might get \u2018added\u2019 to the shed anyway.<\/p>\n

 <\/p>\n

One thing was quite clear to me as I begun my search for the pipe of choice on my GS. A flat twin is never going to sound like an L-Twin, or a V-Twin. Being a vertically opposed engine means it will just never achieve that kind of cracking thump.<\/p>\n

 <\/p>\n

Confused by this, I asked a die hard beemer fan, and several friends when an online mate I have come to admire greatly for his engineering knowhow, explained some science behind pipes, and I think it\u2019s worth sharing, with permission of course.<\/p>\n

 <\/p>\n

Thanks Lordy for the continued engineering lessons mate, top stuff.<\/p>\n

 <\/p>\n

Hey +Dan .. a little one on one free lesson\u2026<\/p>\n

Bear in mind, I\u2019m an engineer and what I\u2019m saying here is a repeat of what I have seen , heard, and worked out\u2026<\/p>\n

You may have heard me talk of the terms \u201cpulse\u201d and \u201d scavenge\u201d
\nSingle cylinder, this doesn\u2019t matter a shit\u20262,3 4 cylinders etc. it can and does make a huge difference.<\/p>\n

Pulse\u2026<\/strong>
\nThink of the block of hot exhaust<\/a> gases travelling down the header pipe as the exhaust valve opens and shuts, obviously, faster the engine is revving, the quicker that pulse belts out..
\nScavenge\u2026<\/strong>
\nIt\u2019s the low pressure bit behind the pulse..<\/p>\n

Now on a good set of pipes, the trick is to time the pulse from cylinder 2, into the scavenge bit behind the pulse from cylinder 1.
\nScavenge effect, tends to pull the pulse, which in turn pulls the scavenge, pulls the pulse etc etc..<\/p>\n

So a top working set of pipes just flow right.<\/p>\n

The really hard thing to get right is the back-pressure created by bends and 2 into 1 (4 into 1, whatever) where one pipe has a tight bend and the other is almost straight..<\/p>\n

You may have heard the expression years ago of \u201ctuned and balanced extractors\u201d .. if they truly are tuned and balanced, the pulses meet at the junction points in a neat line with no gaps between them.<\/p>\n

This is not easy to do on a V Twin \u2026 as you can probably now imagine.<\/p>\n

It\u2019s a fun science and I\u2019m not for a second saying I\u2019m 100% right in what I say\u2026 but the more I think about it, the more I believe I have it pretty bloody close \ud83d\ude00<\/p>\n

 <\/p><\/blockquote>\n

Schooled!<\/p>\n

 <\/p>\n

That really helped my technical understanding of how an exhaust works, and it goes some way to explaining why a flat twin just doest sound the same as a Ducati, or a Harley if you think about it.\u00a0But don\u2019t think too hard, your head might explode like mine did.<\/p>\n

 <\/p>\n

Back to the real question though, and the trouble with buying a pipe: finding out how they sound and perform without buying.<\/p>\n

 <\/p>\n

The evidence was laid out before me.<\/p>\n

 <\/p>\n

The best answer of course. YouTube. So my search began\u2026<\/p>\n

 <\/p>\n

A lot of these videos don\u2019t really help that much, but at least you can kind of get an idea how they sound.<\/p>\n

 <\/p>\n

I have always liked the premium brand of Akrapovic, and as BMW has done the R&D on them fitted to\u00a0the actual bike, it kinda made my decision pretty simple.<\/p>\n

 <\/p>\n

Then I discovered that they came in black. Matte Black. The best kind of black. That did it, I was sold.<\/p>\n

 <\/p>\n

A few quick searches on different online shops and I soon realised there was literally\u00a0no savings to be had in trying to source one online. I found a couple of really cheap Arrows on eBay, but I was concerned about their legitimacy and also shipping.The Arrow also has a much smaller profile and to me it made the bike look out of whack. It\u2019s kind of a big pain in the arse being ten million miles away from the rest of the world, shipping can really sting.<\/p>\n

 <\/p>\n

So off to my local dealer and the origin of my bike revealed that they could indeed be a little competitive for my business, so with a just discount, I had ordered exactly what I wanted from the dealer and within 3 days it was in my hands.<\/p>\n

 <\/p>\n

Bling!<\/p>\n

 <\/p>\n

Installation was piss easy. Two bolts, slip the old one off, a bit of fiddling with the carbon cover and slip the new on one. Job done. 30 mins tops. You can see a bit of glue that has heated up and leaked a bit, checked that out and it turns out to be pretty normal, or so they say. Some WD-40 and it will wipe off.<\/p>\n

 <\/p>\n

The wrap<\/h2>\n

 <\/p>\n

The new pipe sounds great. It\u2019s definitely\u00a0deeper than the stock pipe, which by all counts surely is a very decent stock muffler, but meh. I wanted more black. Quadruple Black?<\/p>\n

 <\/p>\n

So it\u2019s a deeper sound down low, it isn\u2019t super loud (could definitely be louder), but it kind of zings, instead of claps like the Termi on a Ducati.<\/p>\n

 <\/p>\n

It has a really nice note up through the revs heading towards the red line, but it quietens out. It doesn\u2019t get louder, it gets quieter, which is why it\u2019s called a Silencer. Hard deceleration is where it is all at. I like a good bit of engine braking, and the auto-blipper makes a good crackle and pop as you push down through the gears. Noice!<\/p>\n

 <\/p>\n

The verdict<\/h2>\n

 <\/p>\n

It\u2019s a slip-on. A bloody expensive one ($1435 AUD). It looks tuff. It sounds better than the stock. It\u2019s an Akra. What\u2019s not to like?<\/p>\n

 <\/p>\n

Ultimately pipe choice is personal, this probably isn\u2019t that helpful to anyone trying to work it out for themselves, but that\u2019s what you have to do when you boil it down.<\/p>\n

 <\/p>\n

Until next time, ride on.<\/p>\n","protected":false},"excerpt":{"rendered":"

At first I was pretty happy with the stock pipe on my BMW R1200 GS, but after about 7,000kms I knew it had to go; it just didn\u2019t have the character, or note, that I liked.   Ireally wanted that angry twin note, I basically wanted it to sound like my old Multistrada. Thumpy, angry… Continue reading Choosing An Exhaust For A BMW R1200GS<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":383,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"none","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-380","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-general","entry"],"wps_subtitle":"","_links":{"self":[{"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/posts\/380","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/comments?post=380"}],"version-history":[{"count":1,"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/posts\/380\/revisions"}],"predecessor-version":[{"id":384,"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/posts\/380\/revisions\/384"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/media\/383"}],"wp:attachment":[{"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/media?parent=380"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/categories?post=380"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dailybikers.com\/wp-json\/wp\/v2\/tags?post=380"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}