A Call To All Great Exhaust Builders

[foreda]

Exhaust

If we could only reproduce the original exhaust!! Most of you have probalby seen my 79 with the original exhaust and I can tell you the performance is better than any after market exhaust that I have ever tried. If I could find another orignal exhaust for my 78, I would have to jump on it.
If someone were to start building a new exhaust system, you would surely have to also build for other bikes to make a profit simply because there are not that many XS 11's on the road today. Another reason would be most people usually buy these old bikes because they are fairly cheap and don't spend a whole lot of money on them. I spend more than the average guy because I truly love these old machines.

[Mathh]

Quote: Do you mean combining 1,3 and 2, 4? Anything I have read and observed on scavenging combines these cylinders in order to space them 180 degrees apart from intake and exhaust strokes, in order to align these strokes to assist in scavenging, as is not possible with combining 1,2 and 3,4. .

I mean combining 1 and 2 and combining 3 and 4.. That's what i was trying to tell. I also have read about the opposite, but things have changed. The exhausts hanging from my wall all show 1&2 and 3&4.

I'm seriously thinking the Bilzilla exhaust page is outdated. I have just been reading this page:

CLICK

It's about the honda integra that has the same firing sequence as the XS1100 (1-3-4-2-). Chapter 4 explains the difference between the two versions of combining cylinders.

We cannot forget that exhaust configuration is absolutely linked to engine configuration. Is the engine meant for racing or road? That is also what i meant with dual mufflers: on a road configured bike they work better than a 4-1.

And reproducing the stock exhaust.... please make my day There is a guy in germany that makes a neat replica in stainless.. only problem is that it is too expensive. Three years ago I sent a complete stock system (old and rusty) to Poland to a factory that had convinced me they could replicate everything for a decent price. After six months i contacted them and they told me it was impossible for a decent price. But they knew a company in Taiwan that could, so they sent the complete set to Taiwan. I have seen prices for the kwakker KZ900 and H2 sytems and thought if it was in that pricerange i would be satisfied. Only problem is I have never heard from them again.... the factory in Poland explained to me they were too complicated to make cheaply....

[cywelchjr]

I mean combining 1 and 2 and combining 3 and 4.. That's what i was trying to tell. I also have read about the opposite, but things have changed. The exhausts hanging from my wall all show 1&2 and 3&4.

The Jardine Spaggetti pipes do 1,4 and 2,3 and are supposed to work well. I know I like mine.

And reproducing the stock exhaust.... please make my day There is a guy in germany that makes a neat replica in stainless.. only problem is that it is too expensive. Three years ago I sent a complete stock system (old and rusty) to Poland to a factory that had convinced me they could replicate everything for a decent price. After six months i contacted them and they told me it was impossible for a decent price. But they knew a company in Taiwan that could, so they sent the complete set to Taiwan. I have seen prices for the kwakker KZ900 and H2 sytems and thought if it was in that pricerange i would be satisfied. Only problem is I have never heard from them again.... the factory in Poland explained to me they were too complicated to make cheaply....

What about getting the Jardines reprod? Somehow I think they might be easier to reproduce than the stock, although I didn't think the stock pipes were that complex.

[79XS11F]

There's more to building a performance exhaust system then just making it fit the bike. Designing a good exhaust system that will deliver additional power takes some serious engineering and testing. If I were you I would keep my eyes open for a good used RC engineering, Kerker, V&H or Super Trap pipe and refurb it as necessary. Kerkers are not that difficult to find and I see new baffle-less V&H new in the box on e-Bay from time to time. They've already done the research, designing, testing and produce good performance pipes for these bikes. I think in the end you will also be further ahead in cost as well.
Rob

[Larrym]

The original exhaust for my special is hanging in the garage. I took it off to have some rusted out sections of the mufflers welded. In the meantime I installed an original header modified to accept the JCW mufflers. Performance had been compromised a tad and the sound is definitely different without the crossover pipe.

The original exhaust design, material, and construction has some interesting characteristics. For example, while it may not achieve the peak theoretical exhaust scavenging level it is matched to engine in all the ways the engineers chose. One of the major factors that I liked was that the bike didn't sound like it was announcing to world that "something wicked this way comes." Didn't matter whether it was idling or under WOT between 5-8K RPMs. I believe that this was a deliberate move by the engineers who came from a culture where loud, brash, and overt display of power/force was/is considered barbaric/uncivilized. So the exhaust sound or lack of it was a display of that strong "Kung-fu".

The biggest beef I have with the system is that the engineers constructed the system in an "all-in-one" way where once any part of the exhaust failed, the entire side had to be replaced. No way to slide on a replacement muffler. Header pipe dented, broken or crushed? Scrap that entire side. I see this as a major flaw.

If there is to be an affordable exhaust system made for this machine I'd like to see it broken into front header section, middle, and muffler. Each section replaceable/affordable as it wears out or suffers damage. And of course I'd want the crossover pipe for the sound and equalizing backpressure function.

[Mashermoto]

Looks like you gents are in full chat mode...so I've got some work to do

81XS,
I talked to the guy who builds the X-Pipe a couple of weeks ago. The system is probably a pretty good performer. He claims is kicks the rears of other systems. I'm not real crazy about the looks of the standard X-Pipe that only extends about as far as the front side of the rear tire. The system with the MX-3 mufflers looks excellent, but I would like to see it mounted up first. No XS1100 pictures are available. Access to the oil filter is restricted as well. However, the deal killer is the price Those costs shown are for a bear metal system But like I say, I don't doubt the performance claims.

XSLover,
So what’s up with the Jardine Does it look like the one on Bob Jones picture above Does it drag the pavement

T71Ford,
That's excellent information I hope Matth will drop back in a clarify the cylinder match. I understood his post to say that #1 can match with #2, and #3 can match with #4. If they can, that would certainly make the design much simpler. Hope you hang around for a while

TrBig,
I got a PM reply from MeatTooth. He has a new born baby and probably won't be available for a little while. He knows about the post and hopefully will keep in touch. I think he has the means to make something happen.

[79XS11F]

What is the firing order on these engines?
Rob

[Cobia]

Exhausts

Although I do not have access to a dyno system, I've had some experience with several types of exhausts.
My '80G came with a 4-1 Kerker, loads of power and sweet sound, not very loud but authoritative at WOT. Sounded and performed a lot better after wrapping the internal baffle, and no rattling. Great powerband response to this day.
The XJ came with the RC Engineering 4-1 and like the G, sounds great and the power just pours on. Had trouble in the 1.8k to 2.2k rpm range until I installed larger pilot jets. That smoothed everything out.
The '79F came with SS Jardine spaghetti 4-2 turn outs. I loved the sound of those so much that I kept them when I found a set of 'like new' stock replacements closeby, for $40.00 on ebay and 45 mins away!!
I replaced the Jardines with those and sold the bike. Didn't notice much performance difference between them but the difference in the quality of the sound was significant. Looking to eventually install them on the G and store the Kerker for when any of them suffer the inevitable.
In reality I thought the Jardines performed better than the stock replacements I found, but it could just be a sound thing.
Just my 2 cents worth.

[Mashermoto]

OK, I just posted my reply without seeing that there was another page of information posted

Mathh,
If #1 will match with #2, and #3 will match with #4, then the design is much simpler. In fact the MAC system shown above would work out if only it had a better looking muffler design

[crazy steve]

....One of the major factors that I liked was that the bike didn't sound like it was announcing to world that "something wicked this way comes." Didn't matter whether it was idling or under WOT between 5-8K RPMs. I believe that this was a deliberate move by the engineers...

The biggest beef I have with the system is that the engineers constructed the system in an "all-in-one" way where once any part of the exhaust failed, the entire side had to be replaced. No way to slide on a replacement muffler. Header pipe dented, broken or crushed? Scrap that entire side. I see this as a major flaw.

I think the quietness of the bike had several origins. One, federal noise standards were already in place to some degree (and stiffer ones were coming) so they were meeting current ones and getting ready for the future. But maybe the biggest reason is this bike as originally introduced was touted as a 'do it all' machine, equally at home putting fear into it's competitors yet able to cruise as the equal to any touring bike. Listening to exhaust drone while going at a steady 70 mph was considered poor form and if you wanted to out-do BMW it had to be quiet.

And yeah, the exhaust design is a crime. But in Yamahas defense, this was fairly standard practice among the Japanese manufacturers at the time and you'll find this among all of them. The real crime was their use of light-gauge metal for too much of it (leading to cracks and rust-though) and it's replacement cost. Even when new factory exhausts were still available, they were horribly expensive.

And if you want to see some 'design flaws' right next to some excellent engineering, buy a Jaguar V-12 car....

'78E original owner

[Pat Kelly]

[QUOTE=Mashermoto;255292]Looks like you gents are in full chat mode...so I've got some work to do

81XS,
I talked to the guy who builds the X-Pipe a couple of weeks ago. The system is probably a pretty good performer. He claims is kicks the rears of other systems. I'm not real crazy about the looks of the standard X-Pipe that only extends about as far as the front side of the rear tire. The system with the MX-3 mufflers looks excellent, but I would like to see it mounted up first. No XS1100 pictures are available. Access to the oil filter is restricted as well. However, the deal killer is the price Those costs shown are for a bear metal system But like I say, I don't doubt the performance claims.

[QUOTE]


A while back I sent a message via Ebay to the person making the X-pipe. I was wondering if it was my old friend Pat Egan. Pat designed and was the original maker of the X-pipe. This guy said he wasn't Pat but he was very curious how I knew Pat.
Pat and others I knew were using the X-pipe on their KZ750's they were racing (Pat wasn't racing anymore at that point). The X-pipe was a well balanced, light system. It was one piece with removable baffles. Pat showed me a quirk with the exhaust. With the bike idling he put a small piece of paper by the outlet of one muffler and let it go. I was sucked in and would pop out the other muffler. The body of the 'X' is a large chamber. All 4 headpipes dump into this common chamber, almost like a large volume collector. It was designed for racing, but in the late 70's we were at the leading edge of what was to become the sportbike genre.
I still have the original exhausts for both my bikes. You guys have almost talked me into putting them back on.

[T99Ford]

D-oh!

Sorry for my mistake!I mistyped in my earlier post. It should have read 1,4 and 2,3 connected in a 4-2-1, just as with Cy's X-pipe configuration. This is for the reasons I listed earlier, namely the 180 crank design of the four stroke engine. I had to go and look at my bike to make sure, but 4, 1 and 2, 3 are baffled together, prior to the can. In addition to the scavenging benefits listed above, the header lengths for this cylinder configuration are the same. I can't say I really understand the advantage of the 1,2 and 3,4 design for scavenging, unless that is used on a bike with a different firing order than the XS. I may be wrong, though, and am simply unaware of the changes in exhausts that make this possible. Most of my research prior to my exhaust mods indicated the configuration I used.
As I said earlier, this took a dropping power curve from 50-60 mph and made it a flat one, with a slight rise. The A/F ratio is still rich at this point, but the bike was very streetable (and the midrange A/F was adjustable with needle shape/ position).This was all verified on a Dyno Jet dyno.
I will go out on a limb, and say that just because the engineers at Yamaha designed and built the XS11 with a 4-2 that it is the best system for the bike. The engineers were attempting to achieve the most rideable through most of the power band with this exhaust. As many here will attest, they succeeded marvelously. But as with everything there were compromises. At least top end would have been sacrificed. An important part of the whole "make our own exhaust" needs to include a careful study of the specific end use of the bike. This will ultimately determine the exhaust that would be made.
I would venture most would want a 4-2. But there are some (maybe only a few) that still desire the howling death wail of the 4-2-1 wound to 8000 RPM!

[81xsproject]

...I would venture most would want a 4-2. But there are some (maybe only a few) that still desire the howling death wail of the 4-2-1 wound to 8000 RPM!

Me for one. I not only love/prefer the sound of a nice all-to-one exhaust, but like the looks as well. I would do 4-2 for the x-pipe, though.

I only have experience with one 4-2-1 and it mated #1-#4 and #2-#3. It was on my buddies KZ. It was replaced by a V&H street 4-1 which was a noticeable drop in performance.

[daveyg]

When I worked as a technician at a local Yamaha stealership, I noticed almost all 4 cylinder bikes I worked on (From the R6 and R1, to CBRs, to GSX-R) almost all used a 1,2 and 3,4 tri-Y system, and all of which, from my research, were 180 degree engines with a similar firing order, if not just flipped, to our beloved XS11s (With the exception being the latest generation of R1 that uses a 90 degree crank) So if those wonderful Japanese engineers think it works so well... Maybe it does...

[cywelchjr]

When I worked as a technician at a local Yamaha stealership, I noticed almost all 4 cylinder bikes I worked on (From the R6 and R1, to CBRs, to GSX-R) almost all used a 1,2 and 3,4 tri-Y system, and all of which, from my research, were 180 degree engines with a similar firing order, if not just flipped, to our beloved XS11s (With the exception being the latest generation of R1 that uses a 90 degree crank) So if those wonderful Japanese engineers think it works so well... Maybe it does...

I suspect that the reason it's that way on factory systems that do that is really more because of ease of production really. While they are after performance, they are also after easy and inexpensive production at the same time, so if they can make it perform almost as well with 1,2 and 3,4 paired as with 1,4 and 2,3 paired, cost and complexity would tend to push them towards the simpler option.