pannier pipe extensions ... what effect do they have?

retroman

retroman

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... these ruddy great bits of pipe that are provided to clear box panniers and indicators etc ... what, if any, difference do they have re: engine and exhaust function?

Please explain in words of two syllables or less, if applicable :thumb
 
It depends what you know

1/If you know nothing at all about exhausts or engines,they're fine,slap them on and ride away.

2/If you know a bit about exhaust constructuion,swept volumes,shatter waves,gas expansion,low and high exhaust valve pressure and valve gas clearence speeds as well vacuum and extraction effects,they're crap horrible and nasty bodges that are not fit to throw at scabby cats,don't go near them.Why do you think mBw exhausts end where they do?That's what a bloke down the pub said anyway :beer:
 
Vern said:
1/If you know nothing at all about exhausts or engines,they're fine,slap them on and ride away.

2/If you know a bit about exhaust constructuion,swept volumes,shatter waves,gas expansion,low and high exhaust valve pressure and valve gas clearence speeds as well vacuum and extraction effects,they're crap horrible and nasty bodges that are not fit to throw at scabby cats,don't go near them.Why do you think mBw exhausts end where they do?That's what a bloke down the pub said anyway :beer:
Click to expand...

.... so I take it that you are against them, Vern?

Just got my bike running sweet after months of cough'n'splutter via Remus, so bollox to that.

:thumb
 
Vern said:
1/If you know nothing at all about exhausts or engines,they're fine,slap them on and ride away.

2/............they're crap horrible and nasty bodges that are not fit to throw at scabby cats,don't go near them.Why do you think mBw exhausts end where they do?
Click to expand...
So removing the CAT or fitting anything but an original MbW silencer not will affect these carefully balanced exhaust harmonics but a six inch extra bit of pipe will? :confused:
 
If you remove the cat,put an aftermarket exhaust on it or stick a six inch bit of tube on it,you WILL effect the way the engine and fueling operate.

When you make a proper exhaust,the amount of penetration on the welds makes a difference to how the engine works,and can be shown at different rev ranges on a dyno when you're developing the exhaust.

If you want the real truth about exhausts,I would say that 99% of people who tamper with exhausts on their bikes/cars,wouldn't know the difference if you stuck a spud up the end of it,let alone talk about dynamic balancing.As long as it makes more noise,it goes faster,that's what really sells exhausts these days.

Finally,you will be very hard pressed to get an exhaust that will perform it's overall job better than the OE one fitted to any bike.They just don't make enough noise for most people,that's all.
 
I won't get involved into the technical discussion as I'm not qualified, but I've just installed an extension coming with my Touratech Special set (2x41L), great piece of kit by the way, and very affordable in France!
As soon as the piece was fitted (correctly, needless to say), it felt like the bike had lost some power. I don't know how much, but enough for me to notice and take it out while I'm in town. I only put it on when I do long distance riding and when the cases are on...
I guess the main use is not to burn the left case or blacken it, so when there is no case on, I'd rather get my full power back. I may have to protect the cases' frame in order not to get that burnt though. My .02 cents.
 
Manni said:
As soon as the piece was fitted (correctly, needless to say), it felt like the bike had lost some power. I don't know how much, but enough for me to notice and take it out while I'm in town. I only put it on when I do long distance riding and when the cases are on...
Click to expand...

This would worry me ... nature of the beast is that when your panniers are on you will be riding for the greatest distances over long stretches of time ... not good, surely

:(
 
Manni said:
I won't get involved into the technical discussion as I'm not qualified, but I've just installed an extension coming with my Touratech Special set (2x41L), great piece of kit by the way, and very affordable in France!
As soon as the piece was fitted (correctly, needless to say), it felt like the bike had lost some power. I don't know how much, but enough for me to notice and take it out while I'm in town. I only put it on when I do long distance riding and when the cases are on...
Click to expand...
I'm not technically qualified either but I can't really see that whatever difference a little bit of pipe may make is going to be noticable.

I've never ridden my bike without the 41 litre TT panniers and the extension pipe so I can't make any comparison. I'm fairly certain that any performance benefit from not having the extra bit of pipe is likely to be out-weighed by their ferkin enormous drag!

I'm sure I must be missing something here. :confused:

Many of us hang sodding great boxes off the side of our bikes. Even the most streamlined offerings are as areodynamic as Stonehenge, yet a little bit of extra pipe might affect the bike's performance?

I have the extra bit of pipe fitted because it stops the contents of my left pannier being cooked and I've seen what happens to the plastic bits at the back end of the bike when you don't fit it.

I'm sure that whatever loss of performance that pipe provides, it's offset by the fact that I don't have to spend money replacing the contents evey ride.
 
FWIW

Rode from Marbella to Bilbao in a day in July with a Y piece, Remus Revolution (baffle in) and system panniers on a very HOT day. No melting problems encountered.


Mike R
 
I stuck on the aluminium heat shield things that are supposed to stop the LH system case from melting.

To be honest, even after along run the case doesn't seem to get hot at all with OR WITHOUT the Remus extension.

What the extension does do is direct the sooty exhaust gases away from the back of the numberplate ....
 
MikeP said:
I'm not technically qualified either but I can't really see that whatever difference a little bit of pipe may make is going to be noticable.

I've never ridden my bike without the 41 litre TT panniers and the extension pipe so I can't make any comparison. I'm fairly certain that any performance benefit from not having the extra bit of pipe is likely to be out-weighed by their ferkin enormous drag!

I'm sure I must be missing something here. :confused:
Click to expand...

Just to clarify (and with all respect :) ), you may be missing something because you've never ridden your bike without the extension and the 41L TT panniers...

I ride my bike most of the time in town, except when I commute between Paris and London (once a month), or go touring in the South of France (I ride about 12-15 000 miles a year, all year round, as my bike is my only vehicule). I recently replaced my BMW system panniers witht the Touratechs because I needed more packing space when travelling.

When in London or Paris, I take the extension off (the cases are off as well, I use a topcase in town 99% of the time), because believe me, you DO sense the difference. I've never fitted any "performance" exhaust, I've got the stock exhaust on my bike, but I don't like feeling like my engine is underwater (slight exageration, but true).

When I go touring / long distance commuting, I put the extension on, as well as the cases (which are therefore never on without the extension, so no risk of burning / blackenning anything).

Yes, it's long distance riding, but mainly on the motorway, and for a day or two, at a steady - mostly legal - speed. When I get wherever I'm going, off goes the extension, as well as the cases.

I don't see why I should spend 340 days in the year with a choking bike only because I need my cases the rest of the 25 days... :nono

Regarding aerodynamics, I find that the cases (couldn't see a difference between the Touratech and the System cases from that respect) actually make the bike more stable, especially when heavily loaded, and I've never felt any difference with or without the topcase (Givi 52L). I think the hand protectors (especially with the Touratech risers) make much more of a difference, not to mention the screen of course (I got a tobinated CEE bailey adventure on).

But that's only me...

Try riding without your cases and the extension, you may discover a new bike! :clap
 
Manni said:
Try riding without your cases and the extension, you may discover a new bike! :clap
Click to expand...

Hmm!

I have ditched the CAT (I want to do my bit to save the planet), kept the standard silencer with the extension pipe. Most of the mileage I've done has been fully laden (up to 460 kilos, me and the bike). I'm quite happy with whatever loss of performance the extension pipe might cause.

I didn't buy this (or previous GS's) for performance so any 'loss' isn't important to me.

Having seen Reyno's rear Zega mounting (and idicator stalk if I remember correctly) at Llangollen earlier this year after one trip without the extension pipe, I'll keep mine in place thanks.
 
Vern said:
....Finally,you will be very hard pressed to get an exhaust that will perform it's overall job better than the OE one fitted to any bike.They just don't make enough noise for most people,that's all.
Click to expand...

Vern said:
.I'm going to make my money from other bike luggage and one off exhausts, and not this club
Click to expand...

So what are you going to be doing in terms of development work to offer an improvement on BMWs R&D ? C'mon you can't give us a teaser and leave us hanging....spill the beans man! :)
 
MikeP said:
Hmm!
Having seen Reyno's rear Zega mounting (and idicator stalk if I remember correctly) at Llangollen earlier this year after one trip without the extension pipe, I'll keep mine in place thanks.
Click to expand...

That's interesting. But can you explain why having the Zega frame put on the bike could have the effect of burning/damaging the indicator stem, when the said indicator stem is fine as standard, with the standard exhaust? I can't understand.

Using the cases without the extension for a long journey on the motorway, as I assume your friend did, is bad, but again, I never do that. I only take the extension off when the cases are off, and I'm riding short distances, mainly in town.

And as of today, I can see no damage to the tube holding the cases (which I may try to protect one way or the other, as I'm a bit concerned with that, as I said in my first post), or to the indicator stem...
 
Most of the exhausts I'll be making will start at about the 2k mark,mass production of the so called "y pieces"(and I've yet to see a good one,I made one,and it worked out at about £650,so I shelved it as people wouldn't pay that much for it+a couple of dyno runs)

I'll see if I can dig out a picture of a decent exhaust for you later ;)
 
Vern said:
Most of the exhausts I'll be making will start at about the 2k mark,mass production of the so called "y pieces"(and I've yet to see a good one,I made one,and it worked out at about £650,so I shelved it as people wouldn't pay that much for it+a couple of dyno runs)

I'll see if I can dig out a picture of a decent exhaust for you later ;)
Click to expand...

Cool.. I'd like to see that. Yeah, people will spend money on all sorts of things, but no one wants to pay for quality these days. :( Take B&Q as an example, when they started out they used to sell decent tools alongside the "lesser quality" stuff. It didn't last long though, did it? They didn't sell enough high end equipment to make it financially justifiable, so most of the good stuff went..Ooo, this is turning into a rant..sorry! :eek:
Back on track... have you got Dyno curves with/without extension pipe? I'd love to see the difference.
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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