Complete, Now Selling: Yoshimura Replica 9/11F SS Exhaust.

Posted: Tue Jan 26, 2016 5:34 pm

Quick update, bikes at the shop. They are ordering material and some pieces from cone engineering. They also ordered some bends for the machine to make the exhaust. coming along, will dyno my bike either this or next week.

I'm busy this week prepping for a 3hr iron man race + 5 hr endurance team race.

Posted: Tue Jan 26, 2016 7:51 pm

toddk wrote:

So, I'll add my 2 cents Shocked

,

Hindle makes excellent stuff.

I had their pipe on a GPZ900 and a VF1000R - remarkable, in both cases they were very strong in midrange improvement - the only pipe manufacture product I've tried and achieved a bit of a wow factor by just fitting a pipe, the GPZ actually learned to lift the front wheel all by itself after fitting their pipe

Posted: Tue Jan 26, 2016 9:13 pm

Just for search functionality, can we keep this related to yoshimura pipes? I'd be very interested in a hindle exhaust thread if you wanted to make one. I've been in a CB-F exhaust binge lately. Very Happy

Hawk Joined: Jan 10, 2012 Posts: 452 Location: Chicago

Z3RO wrote:

Quick update, bikes at the shop. They are ordering material and some pieces from cone engineering. They also ordered some bends for the machine to make the exhaust. coming along, will dyno my bike either this or next week.

I'm busy this week prepping for a 3hr iron man race + 5 hr endurance team race.

Thanks for the update Chris....Good luck with the race...

E

Posted: Wed Jan 27, 2016 12:56 am

Are the pipes going to be mandrel bent?

Posted: Wed Jan 27, 2016 1:54 am

Id be interested in why you wouldn't use captains measurements? Just make them fit (bends) and mount the Yosh can on that.

Ive got the measurements if you want them. Header length, collector specs etc.

Will this header be wide enough to service the oil filter?

Since you got MotoGP Werks out of this, I'm interested!!

Posted: Wed Jan 27, 2016 3:17 am

Thanks Chris

Posted: Wed Jan 27, 2016 3:31 am

Shawn_Mc wrote:

Id be interested in why you wouldn't use captains measurements? Just make them fit (bends) and mount the Yosh can on that.

Ive got the measurements if you want them. Header length, collector specs etc.

Will this header be wide enough to service the oil filter?

Since you got MotoGP Werks out of this, I'm interested!!

This project was to replicate a yoshimura exhaust. But send me captain's specs and I'll compare. Are these specs meant for his beast machine? Cause if so, I don't know many people who are at his level. Maybe he can chime in. I have no idea if a stock F bike can take advantage of his headers. I am a big fan of Captain and would love to hear his input.

The exhaust will be a complete system and have access to all service points and center stand.

And motogpwerks is not in this, I cut him out because after a 30 min convo he hasn't replied to me about the questions we had. I didn't feel like nagging him to help him make business so I found a a local metal fabricator shop that does a lot of stainless steel work and they agreed to do it for me. I'll be making a prototype first and so you all can see and hear the pipe.
Even if no one wants one, I'll still be happy, haha.

This is what he bends on:

Posted: Wed Jan 27, 2016 3:55 am

Cant wait to see it!

Posted: Wed Jan 27, 2016 2:08 pm

Shawn_Mc wrote:

Id be interested in why you wouldn't use captains measurements? Just make them fit (bends) and mount the Yosh can on that.

Ive got the measurements if you want them. Header length, collector specs etc.

Will this header be wide enough to service the oil filter?

Since you got MotoGP Werks out of this, I'm interested!!

Here are the dimensions that Captain uses for his primaries and collector.

Posted: Thu Jan 28, 2016 12:18 am

Z3RO wrote:

The pipe I'm making will make it mount up to stock rearsets. If someone who is buying the pipe has different rearsets, or doesn't want a mounting bracket, we can work something out.

Dropped off the bike yesterday, with a full spec sheet of a yoshimura race can. Thanks to a fellow forum member, I have measurements from the entire pipe from port to tail. Will be using 304 stainless steel, and if needed, cone engineering components. I'm going to dyno my bike with my mac 4-1 exhaust and then dyno the yoshi prototype pipe. See if we can get some numbers off the same dyno. The shop will be finishing an order this week, so progress will be slow, I will update as I can. Hopefully have a prototype soon in the next couple of weeks.

Thanks for everyone's interest.

Chris

I like what you are doing about accessing the service points. I had a Yoshimura exhaust and you cannot access the oil filter or oil drain plug with the pipe on.

Also, I do want the exhaust but not the Yoshi style that's designed to work with passenger pegs. I wanted the up-swept style. Is that possible? Maybe just a different mid-pipe? Here's my current setup, looking for something similar to work with my after market rearsets:

No room or need for passengers on the hot rod...

Posted: Thu Jan 28, 2016 12:33 am

This first run will only be for the style shown on the first page. I started thinking about doing different can styles (Bassani, Wolf, Valesco etc.) using the same header but I felt like I was getting a head of myself. I wanna make sure I make a quality exhaust so I'll be trying to focus on the project at hand. Maybe later down the road? I got a lot of stuff going on atm so I think it's best for me to just stick to this one thing. But who knows, maybe I end up really enjoying this process and will keep at it. Sorry this wasn't really a good reply...haha.

Got cash to burn? http://japan.webike.net/products/9673474.html

750 version: http://japan.webike.net/products/21592498.html , http://japan.webike.net/products/21592492.html

Posted: Thu Jan 28, 2016 3:16 am

Z3RO wrote:

Got cash to burn? http://japan.webike.net/products/9673474.html

That's if you want to burn a little cash... Smile

This is burning major cash: http://japan.webike.net/products/21446820.html

$2378.04 USD Shocked

Posted: Thu Jan 28, 2016 3:29 am

Z3RO wrote:

This is what he bends on:

But you didn't anwer my question; is that a mandrel pipe bender? If not, then I'm out.

CB1100F Joined: Feb 17, 2009 Posts: 2111 Location: Oz

From the picture it quite obviously is a mandrel bender.

Posted: Thu Jan 28, 2016 5:36 am

I couldn't answer because I wasn't sure. lol. I was hoping the picture would answer the question.

Posted: Thu Jan 28, 2016 1:46 pm

DonR wrote:

From the picture it quite obviously is a mandrel bender.

+1

Posted: Fri Jan 29, 2016 5:40 am

Z3RO, Thanks for doing this -- keep up the good work.
The picture clearly shows an outside mandrel but an internal mandrel is used sometimes when the tubing is thin and the bend radius is shorter (tighter). The internal mandrel keeps the tube from deforming inside for smoother bends. Have you determined the tubing wall thickness you will be using?

Posted: Fri Jan 29, 2016 7:21 am

The yoshimura pipe varies at different parts of the exhaust. from the port, it's 1.75'', then it tapers to 1.6'' until it meets up with the 3'' collector. Then it's 3'' until the can which is 3.5''. Doing some R & D on the exhaust and trying to figure out how to keep the look while getting some performance out of it.

Posted: Fri Jan 29, 2016 8:02 am

Z3RO wrote:

The yoshimura pipe varies at different parts of the exhaust. from the port, it's 1.75'', then it tapers to 1.6'' until it meets up with the 3'' collector. Then it's 3'' until the can which is 3.5''. Doing some R & D on the exhaust and trying to figure out how to keep the look while getting some performance out of it.

I think if you used Captain's header and collector specs and then just ran the 2.25" back to the 3.5" can. you'd have a great system. As long as you use a straight through 2.25" core, it'd sound great.

I'm assuming your measuring the OD's of the header tubing. The ID is the important part at 1.5.

You could go from 2.25 at the collector back to a 3". it'd scavenge like crazy (a good thing)

CB1100F Joined: Feb 17, 2009 Posts: 2111 Location: Oz

Well that all depends on what rpm you want your HP peak and the overall spread of power which involves cam timing. In reality there's no such thing as the one perfect pipe for every engine combination.

Posted: Fri Jan 29, 2016 10:52 am

DonR wrote:

Well that all depends on what rpm you want your HP peak and the overall spread of power which involves cam timing. In reality there's no such thing as the one perfect pipe for every engine combination.

Yup, but we can probably make a good street pipe that will be loads better than what most guys are running. Everything kinda depends on everything else.

Posted: Fri Jan 29, 2016 10:06 pm

There's just something about that collector sketch... I can't take my eyes off it.

CB1100F Joined: Feb 17, 2009 Posts: 2111 Location: Oz

Check out Burns Stainless if you're into collector porn.

Posted: Fri Jan 29, 2016 11:10 pm

it looks like a hairy crack to me. roflmao

Posted: Sat Jan 30, 2016 12:42 am

headless wrote:

it looks like a hairy crack to me. roflmao

+ 1

Posted: Sat Jan 30, 2016 12:56 am

Forum member Sonicrete spoke long and in detail about exhaust system design. Don't dismiss what he said as fundimently he seems to have researched it in depth.

Captain

Posted: Sat Jan 30, 2016 4:07 am

I've actually been reading his posts, just in case anyone else is interested I can drop in his posts here. If anyone else have other threads/links to share, please do!

Quote:

Sonicrete:

http://www.cb1100f.net/modules.php?name=Forums&file=viewtopic&t=64496&highlight=exhaust+header

Some years ago it was found that a really odd system worked well. It was basically a box of 15 times cylinder volume and all 4 pipes dumped into it,with an outlet muffler on the box.

This basically eliminated all the waves that could interact both good and bad.

I always thought on a Tri "Y" the second section after the first combine needed to be enough volume to contain total exhaust at that point.

Easy one to see is on a vertical twin bike 360 degree crank. Common was two pipes,either muffler or megaphone. Obviously the exhaust "blob" was like a train going down the tracks,then was empty till the next blob. So by combining the pipes,same diameter in and out,could use one muffler vs two.

Tuning wise a megahone adds a little bit to the tuned length. It mostly acts as a variable length for the wave reflection. This spreads out the tuned length vs a pipe of one length. Megaphones always acted as some sort of extractor,then you could argue about the angle of the meg.

A long pipe acts like a muffler so the power is down low but not up on top.

So you have the two versions the best "muffler" acts like that extremely long pipe and a megaphone is some sort of amplifier that usually pulls more jet.

Example was the Eddie Lawson Z-1 Kawasaki based race bike. This is not the street version. Kerker made a special full megahone pipe. It was a continuous taper from the head,including the bends,till it made the collector,followed by the megaphone. This made a pipe that "worked" at any rpm.

http://www.cb1100f.net/modules.php?name=Forums&file=viewtopic&t=35423&highlight=exhaust+system+design

Full of shit.

The problem is no one that builds exhaust systems knows what the fuck they are doing now since Dennis Dean (Denco) is no longer in business. A 4 into 1 pipe will make more power EVERYWHERE,I figure the power at 1500 RPM is not where you run,and from 2500 RPM up you will be dead meat with the 4 into 2 into 1 shit.

I had to change my nice full pyramid,tricone,RPO Denco system over to a Vance and Hines sidewinder to pass the "block of wood" test,ie 2" ground clearance,and lost .3 sec. The flat collector just kills power,more junk. The Dean system was special,the collecor was not "square" but a parallelagram,1/4 was on the close side and 2/3 the long distance. This made it draw better on 1/4 and made the inside pipes 2/3 not as much,so jetting would be "square" same on all carbs. The collector fires rotating and there is a pyramid inside to streamline the merge,took car header builders what 20 yrs to discover this "merge" collector. This makes the collector as small a volume as possible and THIS is why they work down low. Most pipes have a giant volume collector and a large diameter where it enters the megaphone,this is the primary reason they are dead from say 3000 to 5000 RPM,think junk assed MAC pipes. No one but Dennis made a tricone megaphone,just changing the meg from a single taper to the tricone felt like another cylinder came in. We used to change it if the track had no traction,since the tricone would just shread the slick.

Now if the game is noise forget it. The tricone rattled the windows in the tower to the extent the track owner wanted us to stop doing the burnout,fearing we would break the glass. Everybody near it would hold their ears and this is at a drag strip,the sound is unreal. It is so loud my record is the cops showing up at my shop in 2 minutes firing it up INSIDE a closed concrete block building. Our joke is this is the reason for Zombies,not only does it wake the dead,they stand in line at a phone booth to call the cops.

The main gain for a pipe on each side is to confuse the decibel meter,so it can run less "muffler".

You miss the point.

The diameter through the muffler is the same diameter as the collector. This "acts" like a long piece of straight pipe and is very quiet. The collector is where the magic takes place and is the reason junk pipes are,well,junk.

Easy description. Take a 360 degree twin with both pistons rising together. The diameter of one pipe combines with the other at the same diameter to enter the muffler or megaphone. It is effectively saving the weight of one muffler since only one cylinder fills it at any time.

That picture of the nice chrome 4 into 2 into 1 is junk at its best. Combining 1&2 together and 3&4 together will restrict the flow of cylinder two entering the junction because "surprise" the pipe is the same diameter. Now more error when the flow again combines both sides into one again at the same diameter,never mind the lousy entrance angle,another error. Looks pretty,but designed badly.

There are two things happening at the same time. There is "plumbing flow" just the volume of exhaust going down a pipe and more important the use of the sonic resonance superimposed on the moving exhaust flow. There is pressure in the cylinder when the exhaust valve opens. This is a positive "pulse" that continues down the pipe till it "sees" a change in area and reflects to arrive back at the head as a negative pressure pulse timed by RPM to arrive at TDC on overlap to help pull in the new charge. Any non megaphone version is effectively a long straight pipe,even a straight open pipe acts like a muffler,a restriction to flow,and how much is how long the pipe or plugged up the muffler. The megaphone acts like a pipe of various lengths to s p r e a d the range of effectivity over a larger RPM.

If the pipe primary is too long the bike runs fine,just not a fire breather,but no flat spots. The exhaust must "fight" to get out but no bad vacuum effects. This length is closer to 40 inches and the reason a car runs like it does and more important the reason a car will not run when the muffler falls off leaving a head pipe too short. This is the reason a pipe like a MAC runs like crap. The reflection occurs at the junction being only the short primaries because the "collector" volume is like no collector at all. Yoshimura used to make junk designed pipes. A big diameter piece of straight pipe formed into a square to fit over the four primaries,no collector at all.

Power wise the design should be a full taper starting right at the head. This spreads out the effective RPM of the vacuum effect to boost power.They are not made this way because you cannot "bend" a cone. The Kerker made high bucks factory superbike pipe used on the first Eddie Lawson "race bike" was made this way. The regular people available production Eddie Lawson just had a regular Kerker and people thought these were the same bike. The production bike was a "Green" Z-1. The race version had 8 12mm spark plugs instead of the normal Z-1 4 angled 14mm plugs. There was suspension and brakes differences also. This special pipe just had a nice collector to continue the taper of the head pipes.

For me I want a plugged up perfect design,nice and quiet,but made so the muffler/baffling will come out for "tuning" to the noise I can stand.

Remember the line about the muffler is a restriction to flow?

The more muffler volume the less the restriction,that is it.

Old time design for auto to get the lowest restriction was all the pipes are the correct primary length and enter a "box" of 15 times the swept volume of one cylinder. On the other end of the box was the muffler to let the exhaust out. The volume of the box dampened the pulses and became a constant leak at the end.

None of these are a system tuned for power.

Old design reason. All bikes had an open straight pipe and had to be a certain lenght per rules at the time. Someone discovered that cutting the length shorter made the bike faster,but was now illegal so made a funnel(megaphone) on the end to get the length the rules needed. The end result was even faster. Then they played with the angle of the megaphone and discovered megaphoneiteous. Above a certain RPM they really ran,but below you could not accelerate. Fall "off the pipe" in a corner and you ended up downshifting a lot to finally get it to run again.

In the history of motors there are only two good examples,a Manx Norton,and a Cosworth. These developed more than 200psi of Brake Mean Effective Pressure(BMEP),the standard of how good the motor could breathe. This did a calculation of the horsepower made and related it back to an average over the entire stroke. The Norton had a megaphone of a really severe taper and did the megaphone iteous to the extreme to do it. The legendary F-1 motors multicylinder Hondas of the 60's did not breathe well at all BMEP around 175 psi and considering it was itty bitty pistons a joke,compared to the 500cc single Norton. The Honda made power by simple mechanical means,it would rev a lot higher because of the many small cylinders. The reason for the 6 cylinder. Two cylinder Yamaha against 4 cylinder Honda lost,so more cylinders to get the advantage back. Later to become a V-8 Honda just makes watches,rules disallowed a V-8 so an Oval piston just turned the V-8 into a 4cylinder since no one said the cylinders had to be round. Too bad the rings did not seal the pressure. This thing was slow,so slow that Honda "bought" the last two qualified positions from riders that DID make the field. On the first lap one blew up,on the second lap the second one crashed in the oil the first one put on the track. Honda quits trying a four stroke and makes a two stroke.

Any time you have more than .528 times the back pressure,you have supersonic flow somewhere. The 100 psi in your shop air tank will do it. Simple as punching a hole in the side,the air flow out is supersonic,actually Mach 1 at the hole. Larger hole more flow BUT the air is still only Mach 1 and how you calculate the flow rate. Funny things now happen. In a subsonic venturi,a carburetor,goes from big to small back to big. The air speeds up as it enters the venturi then slows down,this describes how a carb draws fuel out of the bowl. Enough pressure and the air speeds up to sonic at the throat,but now does not slow down but speeds up more. This is how you make a supersonic wind tunnel to test jet designs. This is also describing the new "safety" type shop air blow nozzels,a little hole in the middle with feed holes around the OD that "suck" in more air. A straight wall pipe has the exhaust collect on the inside wall by friction thus reducing the diameter,the flow goes supersonic but an itty bitty remaining hole. Heat addition also drives the flow to supersonic.

Now back to a header with a collector and a megaphone. You have pressure in the motor that leaks away into the collector. At some point this pressure "builds up" inside the collector and this effect takes place to "extract" more flow. If you could ride the bike this way(cops love it) it is loud early and at a certain RPM the sound is all inside the pipe where this change from positive to negative pressure(extracting) takes place,then goes really loud RPM on up. You take a motor with real carbs where wide open is wide open. A restrictive muffler only flows so much main jet,even an open straight pipe not much flow,but a well designed open megaphone just flat DEMANDS more main jet. The reason is it is also drawing more air in and needs more fuel to satisfy the motor.

None of this means much for CV carbs. They are not full open. They only open by the flow of the motor and I would not be surprised to see the slides close near peak RPM as the torque(cylinder filling) drops off with revs. Someone needs to buy one of those "spy" type mini cameras and put it inside the air box to watch and record what happens.

The goal of a quiet system is to interfere with the sound waves,so no resonace tuning,only getting the plumbing restriction as low as possible. The goal of power is to make the motor flow as much air as possible,noise be damned. In fact the louder it is the more pressure(power) you are making and trying to flow as much air as possible over as large an RPM range is the goal. In fact some race systems actually had inserts to put inside the collector to "adjust" the collector volume,but this is mostly a crutch to make up for piss poor calculations on the lengths and areas.

More useless information. Early two strokes made less power than the same size 4 stroke. A guy named Kadency,a proffessor,discovered that if a two stoke port was flat edge and wide the exhaust left so fast it actually pulled the cylinder down below atmospheric pressure. This is what draws the mixture from the crankcase,not the "pumping" action of the piston. It also led to the expansion chamber to use the positive pressures and negative pressures to help empty the cylinder and then form a false wall to prevent the fresh charge from escaping. The shape of musical instruments,especially a trombone,shows and amplifies the different sounds,and also shows the sound (RPM) of effectiveness and the correct tuned lengths to match the RPM the motor runs.

Most exhaust tuning now is just making the least restrictive muffler to meet the decibel requirements and nothing to do with most power possible by tuning the waves.

Posted: Thu Feb 04, 2016 12:46 am

Any progress?

Posted: Thu Feb 04, 2016 1:15 am

Progress is slow, these guys were nice enough to allow to me to stop by the shop after work and teach me the process of exhaust building. This unfortunately will slow things down a bit, but a great opportunity for me. I didn't have my phone charged to take pics, but will do so the next time I'm there. Also talking to different people who are giving me insight on the exhaust build, so meeting with some people next week.

Will keep everyone posted.