Aftermarket intake and exhaust - do I have this right?

[11Rider]

Hi my pals, it's me again. According to my research on this site, my conclustion is that there is little, if any performance to gain with any kind of alterations to the intake and/or exhaust as far as performance is concerned. What's more, performance may even be lost since Yamaha did their homework on the stock system. The only gain to be had is sound/bling. Am I right on this?
PS Regardless, I may go to pods and 4 into one because I'm shallow and like sound/bling

[XS1100_OEM4ME]

Jimho

JIMHO, 1st, there can be huge gains by doing mods to an XS1100 motor, I beleive that a 6.7 sec QTR mile was the best time from mods but that was pro racing team with unlimited $. 2nd, on a budgit, you can make some mods that dont require a master mech deg. to make work OK, pods are one, and she will breath better and carb R/I is easer, I would re-sync carbs at the least. Next, exaust, You can get much more noise out of aftermarket pipes and with some of that "master mech deg." stuff, you "can" even get some preformance increase IMHO. It is intresting to note that Lexus is having Yamaha do the exaust tunning on their new $375,000.00 sports car (yes, that is over a third of a million dollars for a car) so I am guessing Yamaha knows something about tunning an exaust to a motor. Many on here have made aftermarket exaust work, would love to know how much time they shaved off the 11.7 sec qtr time of the pure stock early XS1100, but hey, to each there own. If you do change the exaust you may need to re-jet and will for sure have to re sync carbs. If you got to make more noise and you have a stock XS1100 exaust, please sell it, don't drill/bastard it, they are getting hard to find in OEM condition

[ManagerMike]

Seems you've done your homework. Sound and bling isn't a bad thing however.
I've got pods and they by themselves did wonders for the sound that I hear, even though nobody else gets to hear it. Everybody else hears the exhaust.
I modified the b'jesus out of that as well, but incorporated backpressure so as not to lose all of the low end peformance.

[crazy steve]

Hi my pals, it's me again. According to my research on this site, my conclustion is that there is little, if any performance to gain with any kind of alterations to the intake and/or exhaust as far as performance is concerned. What's more, performance may even be lost since Yamaha did their homework on the stock system. The only gain to be had is sound/bling. Am I right on this?...

Pretty much. There's a few exhaust systems out there that offer a performance increase if you can find one, but it won't be a large gain. Same with pods; a small gain can be had with sharp tuning. For most guys, given the age/wear most of these bikes have and the typical budget, cheap bolt-on power upgrades are nearly non-existant. Not to say you can't make power with these, but it'll be expensive...

[TADracer]

Agree and disagree

Can I agree and disagree? Hmm, I sound like a politician.

The stock exhaust and intake are engineered for, and balanced to, the stock motor and are a bit restrictive to help boost low end power and torque as well as smoothness desired for the street. More power and performance can be gained by aftermaket intakes and exhaust however, it might not be where you want it to happen. Most of the time the power will significantly show in the higher RPM ranges, not suited to street operation. In addition, just changing one or the other will upset the balancing act which means changes and tweeks to alot of other things to get the most out of the machine.

But do it right (takes a long time of trial and error) and you can have the low end power and smoothness as well as the high end performance but you must be prepared to go alot farther than just changing intakes or exhust.

[WMarshy]

Can I agree and disagree? Hmm, I sound like a politician.

The stock exhaust and intake are engineered for, and balanced to, the stock motor and are a bit restrictive to help boost low end power and torque as well as smoothness desired for the street. More power and performance can be gained by aftermaket intakes and exhaust however, it might not be where you want it to happen. Most of the time the power will significantly show in the higher RPM ranges, not suited to street operation. In addition, just changing one or the other will upset the balancing act which means changes and tweeks to alot of other things to get the most out of the machine.

But do it right (takes a long time of trial and error) and you can have the low end power and smoothness as well as the high end performance but you must be prepared to go alot farther than just changing intakes or exhust.

+1 on that, well said.

[11Rider]

Makes sense, thank you.

[fredintoon]

- - - The only gain to be had is sound/bling. Am I right on this?
PS Regardless, I may go to pods and 4 into one because I'm shallow and like sound/bling - - -

Hi Rider,
those are valid reasons but there are also practical ones.
My stock mufflers got replaced when they rusted off the headers. I replaced them with used 1960s Triumph mufflers that cost me $30 the pair at a swapmeet.
That those Triumph bottles look and sound awesome is an unexpected bonus.
I went to pods when I could no longer stand the hassle and blood loss associated with moving the stock airbox to service the carbs.
The bonus there is that now they can be easily got at the carbs don't need to be cleaned anywhere near as much.
As to performance, I dunno. My XS11SG always did have too much power for a timid old man to use anyway.

[crazy steve]

Ok, I'll weasel a bit more...

Mike is correct that power gains can be gotten with the right parts, but therein lies the problem. Nearly all (if not all) the 'good' exhausts are out of production and have been for a long time, so finding one that's 1. complete as made and 2. still in good condition is getting pretty hard. Systems that have been mashed together from bits or having damage may or may not offer any gain and might hurt performance. The still-available MAC 4-2 exhaust won't give any gains as it lacks the crossover of the OEM pipes, so you'll take a hit on power. Exhaust choices is the bane of XS ownership.

Another thing to note is how much power you can expect from this. If you're coming from a V-twin background (or have talked to guys who do), you won't see the kind of across-the-board gains they see with a simple exhaust/AC/rejet change (10 to 20% is typical) as any gains will be at the top end, usually at the expense of low and midrange power. Mike is correct, careful tuning with the right parts can bring that back up to stock output, but don't expect it to be easy. The original combo on the XS is extremely well matched, so bolt-ons can't offer a whole lot over that... JMHO

[11Rider]

Yes, that's what I've surmized. On some of my other bikes like the FZ1 I used to have and my XR650, there were certain intake, timing, jetting and exhaust mods that were commonly accepted as tried and true. This doesn't seem to be the case with the 11. Fortunately for me, the stock exhaust on my '79 Special is almost showroom condition. Maybe some day an amitious 11 owner will do a baseline dyno run and a few runs with some other mods as a comparison.

[crazy steve]

... Maybe some day an amitious 11 owner will do a baseline dyno run and a few runs with some other mods as a comparison.

Search for Dan Hodges' posts, as he did extensive testing/tweaking to see how much power could be had (and at what cost) from these bikes. To make a long story short, small gains weren't too hard to get, but more got expensive...

[11Rider]

Oh great, I'll check it out!

[natemoen]

Well there is always this "exact" reproduction of the stock Special exhaust http://www.xs1100-frw.de/HOMEPAGE_03/Index2.htm (click on XS-Shop on the side and then its the first picture) But this thing is HUGE money.

[b.walker5]

Okay, all this talk of exhausts has created a couple of questions from me.
When I bought my bike, 11 years ago, it came fitted with a NZ made Cycleworks 4-1. It also came with another exhaust which I promptly hung up in my garage and never gave another thought until now. It's a 4-2 with stainless headers and stainless mufflers. I'd say it's homemade or at least seriously modified as the stainless mufflers and headers are welded to mild steel collectors. One of the detachable headers is missing and the other is under my workbench somewhere. Questions are does anyone recognise what it might have been, and is it worth resurrecting?

[MaximPhil]

Okay, all this talk of exhausts has created a couple of questions from me.
When I bought my bike, 11 years ago, it came fitted with a NZ made Cycleworks 4-1. It also came with another exhaust which I promptly hung up in my garage and never gave another thought until now. It's a 4-2 with stainless headers and stainless mufflers. I'd say it's homemade or at least seriously modified as the stainless mufflers and headers are welded to mild steel collectors. One of the detachable headers is missing and the other is under my workbench somewhere. Questions are does anyone recognise what it might have been, and is it worth resurrecting?

Hi Brian,
While not an expert by any means. That looks to me like a stock Special exhaust that has been welded together wrong
In the picture the top one would be the left side. When attached to the bike the "branch line" short piece should tuck under the engine.
The chrome covers look stock with stock bolts.
Phil