Any interest in an actual performance 4-1 exhaust for GS1100E?

[mmattockx]

Is there any interest in a performance exhaust kit for the 1100E models? It should also fit the two valve 1000cc models as well, based on other exhaust fitments I have seen reported here. Tubes would be equal length (true equal length, not marketing brochure 'equal length'), mild steel and CNC mandrel bent with a hand formed collector. Muffler would be up to the end user; my thoughts at the moment are to set it up to use a common muffler such as late model GSXR's or similar, so there is lots of selection off fleabay and the aftermarket.

Note that this would be a kit of loose parts, it would require some welding and final fabrication from the buyer. Price would be pretty high, probably somewhere between $600-$700USD, depending on volume. That is expensive, but it is the curse of low volume manufacturing these days.

I've been looking at doing my own exhaust for a while, but the cost is prohibitive for a one-off. If I can make it into a small batch of systems it might work out and help a few others along the way.


Mark

[azr]

Nice idea, and cutoes on the effort but we can get stainless steel systems for that or less now.

[JTGS850GL]

Price is not going to set well with this crowd. Needing additional welding is a downer as well. Mild steel means painting and rust.

[mmattockx]

Nice idea, and cutoes on the effort but we can get stainless steel systems for that or less now.

Not performance ones, unless you can convince MotoGPWerks to crank out systems again. Systems currently available are far from optimal in terms of performance, this one is designed for performance first.

Price is not going to set well with this crowd. Needing additional welding is a downer as well. Mild steel means painting and rust.

I agree with all you say, they are just some of the choices that have to be made. I don't really want to get into manufacturing exhaust systems, all I really want is one for myself and doing a small batch might make that feasible. The welding is so I don't have to worry about fitment on someone else's bike and mild steel is easy to work on in your garage. Welding stainless means TIG and most guys don't have that option available to them.

I'm just checking on interest before I go to the trouble to model an exhaust system in solidworks to get quotes on the CNC bending. If no one else cares (which is very possible) then I likely won't invest the time to build the model.


Mark

[motogpwerks]

I still make systems now ........they are on ebay usually
Also 2v and 4v and completely different ,maybe the header is the same but the tube size and tail pipe is completely different
No body wants modern muffler ,most guys want something that was peroid correct or close enough as back in the day
Goodluck on buildng you own system

[Nessism]

Seems like a fun project. Do you have performance exhaust design and fabrication experience? Any examples of your work?

I've got an old magazine article somewhere where Joe Minton tested a bunch of different 1100E pipes and only a couple made more power than stock. There is another exhaust system test for the KZ1000, conducted by Cycle magazine, and a number of different pipes made more power than stock but they were all really loud.

To do the job right you would have to build some prototypes and do some dyno runs to see how the power is affected in the real world. Some guideline must be created for acceptable noise levels too.

Good luck

[mmattockx]

I still make systems now ........they are on ebay usually

I will have to keep an eye out for those. Yours are the nicest available for a reasonable price. I agree on the period correct muffler, it is just more effort than I can justify and everybody can do what satisfies themselves.

Seems like a fun project. Do you have performance exhaust design and fabrication experience? Any examples of your work?

I've got an old magazine article somewhere where Joe Minton tested a bunch of different 1100E pipes and only a couple made more power than stock. There is another exhaust system test for the KZ1000, conducted by Cycle magazine, and a number of different pipes made more power than stock but they were all really loud.

To do the job right you would have to build some prototypes and do some dyno runs to see how the power is affected in the real world. Some guideline must be created for acceptable noise levels too.

Good luck

1) No examples of fabrication, I am a mechanical engineer by trade. I am using numbers for the 1100E from a tuner I trust who has lots of experience with these bikes.

2) Yes, noise is a part of making power. I suspect a pipe like I am talking about mated to an OEM GSXR muffler from the SRAD era would make good power and be very quiet. It wouldn't look very good, though.

3) Noise levels are tough, which is why I would leave the muffler portion to the buyer. They can fit whatever they like in terms of sound quality and quantity. Selling a kit would also allow me to sidestep the requirements foisted on aftermarket exhaust manufacturers these days.


Mark

[Steve]

I have always been intrigued by the quest for EXACTLY equal-length pipes.

The problem that I see with that is that all four cylinders will have their peak efficiency at exactly the same engine speed. Yes, that is absolutely GREAT if you only operate the engine at THAT speed. Would be great for drag racing or possibly even some longer-distance road racing, where your engine speeds are very often at, or near, that peak-efficiency engine speed. However, most of us just don't live with our engine spinning at 8000 RPM all day long, so we won't benefit from that PEAK of power from equal-length pipes.

I have a 4-into-1 pipe on my 850. Not for the power, but for the sound. I like the sound of a 4-into-1 pipe, especially if it has a good muffler, which mine does. Overall, I don't think my exhaust system is any louder than stock. It has a smoother sound, due to just one pipe, and is FAR from loud. For street use, I just can't imagine why you wouldn't want to spread the power peak just a bit, and I don't think the 2-3 inch difference in my header pipes (if even that much) is going to hurt overall power.

Good luck with the project, pictures of progress are anticipated and expected.

.

[mmattockx]

I have always been intrigued by the quest for EXACTLY equal-length pipes.

The problem that I see with that is that all four cylinders will have their peak efficiency at exactly the same engine speed. Yes, that is absolutely GREAT if you only operate the engine at THAT speed.

You always want them equal, regardless of what RPM range they are tuned for. If they are unequal you have different cylinders pulling hard at different RPM, which results in them fighting one another and never making best peak torque or power. The 4-1 design also uses pulses from the other cylinders to help scavenging. Unequal length pipes mess this up because they affect the timing of those pulses coming from the other cylinders as well.

A pipe is nothing but a musical instrument and no one would make musical instruments without getting the tube lengths correct for proper tuning, so why should an exhaust system be any different?

There may not be any pics unless I can figure out an affordable way to get tubes bent. Welding the header out of U-bends is tedious, time consuming and not cheap. Getting tubes bent properly is easy (since I already have the design/modelling skills) but significantly less cheap. I will post pics if/when I figure out how to make it happen.


Mark

[Tom R]

There's a motogpwerks exhaust for an 1100e listed on eBay right now.

[Steve]

My point was really that, no matter <what> RPM range they are tuned for, on the street, you will be spending at least 99.5% of your time out of that range, so why does it really matter.

I know there are formulas to determine what length pipe to use for what RPM range you plan to use. I don't have the time or interest to look them up right now, but I did go out and measure the pipes on my bike. Two are 28", one is 27", one is 25.5". That's close enough for MY needs.

.

[sharpy]

Been toying with same idea ...GS 1000 pipes x 4 with 60 degrees.jpg But in there heyday 1000's and 1100's where using Tingate or Megacycle pipes for racing. Tingates even had the cones in the merge collector, Its a Tingate exhaust on my bike. Straight thru muffler but it rumbles really nice. Ally muffler keeps it quiet for what it is.

[mmattockx]

My point was really that, no matter <what> RPM range they are tuned for, on the street, you will be spending at least 99.5% of your time out of that range, so why does it really matter.

A well designed pipe will boost the midrange very nicely and you live in the midrange on the street. While the pipe is tuned exactly for one RPM the effect is not binary. It gives a boost in torque 1000rpm or more either side of the peak, giving a useful range to work with, even on the street.

Aside from puttering through town (where none of this matters), I am between 5000-7500RPM most of the time on back roads and highways. The pipe I want to do will be tuned for a 6000rpm peak, which will be very useable and noticeable on the street. I am also going to degree my cams to compliment the midrange power for an additional boost. I want to get the whole system working together as much as possible.

FWIW, I have a Kerker 4-1 canister system on my bike (I think it was the 'K' system back in the day) and the header on it matches the numbers from my tuner very closely. I suspect that is why the bike runs as well as it does. The problem is the header is old and ratty and beat up some. If I could buy another of those Kerker headers new I wouldn't bother with making one, but they are long since unobtainable.

Been toying with same idea ...[ATTACH=CONFIG]51845[/ATTACH]

Nice looking model. Simple, clean tube design with minimal bending required, that wouldn't be too bad to make from U-bends if necessary. Do you have any details on the tube diameters and lengths on the Tingate or Megacycle pipes? I like to collect as much data as possible from pipes that were known to work well in the past.


Mark

[bobgroger]

Did anyone see the episode on Motor Trend TV, Engine Masters I think, where Freiberger dyno tested a 550-ish HP motor with a set of headers, then proceeded to bash in the pipes with a sledgehammer with another test between bashing? By the time they were done the pipes were neatly flat, and the power was exactly the same. Found it.... https://www.youtube.com/watch?v=azPKIjxmmdU So while I agree an exhaust will make a bit of difference, maybe not that much. Especially without the requisite head, intake, and cams. There was also a test somewhere of a Yoshi slip-on vs. stock on a GSXR, it was worth .7 hp.

[mmattockx]

Did anyone see the episode on Motor Trend TV, Engine Masters I think, where Freiberger dyno tested a 550-ish HP motor with a set of headers, then proceeded to bash in the pipes with a sledgehammer with another test between bashing? By the time they were done the pipes were neatly flat, and the power was exactly the same. Found it.... https://www.youtube.com/watch?v=azPKIjxmmdU So while I agree an exhaust will make a bit of difference, maybe not that much. Especially without the requisite head, intake, and cams. There was also a test somewhere of a Yoshi slip-on vs. stock on a GSXR, it was worth .7 hp.

That makes me feel better about the dents in my Kerker header. A slip on is nothing but a noise generator, especially on current bikes. The OEM's have figured out how to make serious power without the noise and it is really hard to improve on what they supply these days.

On our old bikes going to pods and a good pipe is worth a decent amount on the 1100's and 1150's, but just a pipe alone isn't that big of an improvement. Mostly you gain cornering clearance and lose weight with an aftermarket 4-1 over the stock pipes. I haven't done it to one of the smaller displacement bikes and can't say how they respond. The first gen GSXR's were extremely corked up and removing the airbox, adding pods and a good pipe was worth 20+% more power.

At my elevation (3400ft) my 1100E would have made high 80's for rwhp at best when new. The last time it was dyno'd with the Kerker 4-1 and the rear half of the airbox removed it made 102rwhp. With pods it is now stronger than with the partial airbox setup but I have not dyno'd it since the changes. Just the 12-13% gains made with the pipe and partial airbox are worth the effort, IMO. Going to pods is even better and sorting the jetting isn't that bad on the big bikes. They seem to offer fewer problems in the midrange than the 550's and 650's do from what I have read here. Of course, almost nobody seems to bother to follow a proper jetting procedure and just jumps around willy-nilly and then they are surprised when it doesn't work out.


Mark