What did you do to your Vmax today? Part 2

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GIANT WALL O' TEXT THAT I WISH I HAD TL;DR'ED
Yeah, you managed to write a doctoral thesis without answering my question. Let me make my question a bit clearer...
What is it about the Cobra exhaust that apparently does not allow them to scavenge? The lack of that ungodly huge crossover canister (or whatever the hell it is) under the frame? Too much restriction? Not enough restriction?

You can't fix the cobras. The cure is ufo quadzilla slash cuts.

It has been stated before by me that I think the exhaust you mention is ugly as ****... If I am going to pay a HUGE amount of money for something, it had better look good.
 
Yeah, you managed to write a doctoral thesis without answering my question. Let me make my question a bit clearer...
What is it about the Cobra exhaust that apparently does not allow them to scavenge? The lack of that ungodly huge crossover canister (or whatever the hell it is) under the frame? Too much restriction? Not enough restriction?



It has been stated before by me that I think the exhaust you mention is ugly as ****... If I am going to pay a HUGE amount of money for something, it had better look good.

His thesis was actually quite good I thought.

To dumb it down for you.

Cobras are 4-4.

No crossovers.

Four individual cylinders doing their own thing from exhaust valve to exhaust tip.

Without the benefit of another cylinder helping out its buddy by "scavenging"

This isn't theory. Its scientific fact. Cobras lose horsepower against stock or any other aftermarket because of this. Only an H-D exhaust designer like Cobra could have come up with that.

If you don't like the UFO slash cuts just shop around. There are plenty of choices out there.
Once you get away from heavy as **** stock system, and away from ineffective Cobras, and weed out the various slip ons that do make better power because they keep the stock collector, but are still heavy as **** because they keep that collector; Then your in to the various full systems.

Once there, your choices are 4-1, or 4-2.
They all are about equal really.
The 4-1's making a little better top end power at the sacrifice of a little mid range. Vice versa on the 4-2's

Marks
UFO
Dale Walker
Several Euro makers$$$$!!!!
There are others, just not sure who's still making them for the Vmax.

As for the slash cuts being ugly compared to the Cobras, I don't get that.....I don't have an opinion on the slash cuts other than to say you probably couldn't find a Vmax exhaust that looked more similar to the Cobras than the Slash cuts.....

In the end its really just a matter of taste, what ever blows your skirt up is what's right for you.....

If you really like the Cobras then do it....but your performance will suffer...for some folks that's not a big deal, you just don't see many in the Vmax community willing to give up power
 
I just wanted visual confirmation the switch is on. They did them in a range of colours.

http://www.ebay.co.uk/itm/Illuminat...UE-GREEN-RED-12V-LED-Light-/200851159760?var=

Sent from my Nexus 7 using Tapatalk HD

I already had a switch put in, so I wired up a small LED to it
%255BUNSET%255D.jpg
 
Being in academia, I tried to provide a plain explanation of the question of scavenging. You asked a question, I posted a response. I think it's a hallmark of some of the Short-Attention Span Generation, that they cannot commit to spending less-than five minutes to learn something that they asked-about, and then cast-aside, because of the "time committment." :rofl_200: Those multiple-page menus at a sit-down restaurant must be stressful to contemplate!

We all have our priorities. If you ask a question, please show the courtesy to listen, and read, when someone contributes. If you think it's a thesis, you haven't spent time in the academic world, where 'publish or perish' is the mantra of those seeking tenure. Their answers are much, much longer! No, there are no tenure positions up for acquisition here, but someone did try to answer your question with forethought and using points of comparison to the question of "why don't my Cobras work like that?"

And if you think this is a lot of hot air, "never-mind!" (see the attachment) I apologize for wasting your time, whether or not you read it. :confused2:

His thesis was actually quite good I thought.

To dumb it down for you.

Cobras are 4-4.

No crossovers.

Four individual cylinders doing their own thing from exhaust valve to exhaust tip.

Without the benefit of another cylinder helping out its buddy by "scavenging"

This isn't theory. Its scientific fact. Cobras lose horsepower against stock or any other aftermarket because of this. Only an H-D exhaust designer like Cobra could have come up with that.

If you don't like the UFO slash cuts just shop around. There are plenty of choices out there.
Once you get away from heavy as **** stock system, and away from ineffective Cobras, and weed out the various slip ons that do make better power because they keep the stock collector, but are still heavy as **** because they keep that collector; Then your in to the various full systems.

Once there, your choices are 4-1, or 4-2.
They all are about equal really.
The 4-1's making a little better top end power at the sacrifice of a little mid range. Vice versa on the 4-2's

Marks
UFO
Dale Walker
Several Euro makers$$$$!!!!
There are others, just not sure who's still making them for the Vmax.

As for the slash cuts being ugly compared to the Cobras, I don't get that.....I don't have an opinion on the slash cuts other than to say you probably couldn't find a Vmax exhaust that looked more similar to the Cobras than the Slash cuts.....

In the end its really just a matter of taste, what ever blows your skirt up is what's right for you.....

If you really like the Cobras then do it....but your performance will suffer...for some folks that's not a big deal, you just don't see many in the Vmax community willing to give up power
 

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I took the 85 apart, went from this..........................................to this . Its still a roller Kyle , and a lot lighter :biglaugh:
 

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His thesis was actually quite good I thought.

To dumb it down for you.

Cobras are 4-4.

No crossovers.

Four individual cylinders doing their own thing from exhaust valve to exhaust tip.

Without the benefit of another cylinder helping out its buddy by "scavenging"

This isn't theory. Its scientific fact. Cobras lose horsepower against stock or any other aftermarket because of this. Only an H-D exhaust designer like Cobra could have come up with that.

If you don't like the UFO slash cuts just shop around. There are plenty of choices out there.
Once you get away from heavy as **** stock system, and away from ineffective Cobras, and weed out the various slip ons that do make better power because they keep the stock collector, but are still heavy as **** because they keep that collector; Then your in to the various full systems.

Once there, your choices are 4-1, or 4-2.
They all are about equal really.
The 4-1's making a little better top end power at the sacrifice of a little mid range. Vice versa on the 4-2's

Marks
UFO
Dale Walker
Several Euro makers$$$$!!!!
There are others, just not sure who's still making them for the Vmax.

As for the slash cuts being ugly compared to the Cobras, I don't get that.....I don't have an opinion on the slash cuts other than to say you probably couldn't find a Vmax exhaust that looked more similar to the Cobras than the Slash cuts.....

In the end its really just a matter of taste, what ever blows your skirt up is what's right for you.....

If you really like the Cobras then do it....but your performance will suffer...for some folks that's not a big deal, you just don't see many in the Vmax community willing to give up power

Being in academia, I tried to provide a plain explanation of the question of scavenging. You asked a question, I posted a response. I think it's a hallmark of some of the Short-Attention Span Generation, that they cannot commit to spending less-than five minutes to learn something that they asked-about, and then cast-aside, because of the "time committment." :rofl_200: Those multiple-page menus at a sit-down restaurant must be stressful to contemplate!

We all have our priorities. If you ask a question, please show the courtesy to listen, and read, when someone contributes. If you think it's a thesis, you haven't spent time in the academic world, where 'publish or perish' is the mantra of those seeking tenure. Their answers are much, much longer! No, there are no tenure positions up for acquisition here, but someone did try to answer your question with forethought and using points of comparison to the question of "why don't my Cobras work like that?"

And if you think this is a lot of hot air, "never-mind!" (see the attachment) I apologize for wasting your time, whether or not you read it. :confused2:

I'm sorry... Just 100 tons of **** going on right now, and it feels like at every ******* turn, I'm not being slapped across the face, but literally hit by a friggin bus.

Re-reading what you wrote, it does make sense, but the answer you gave was incomplete for what I was looking for.
No crossovers.

THIS is what I was needing to know.

Now, if there was crossovers, or a single crossover, to be specific, then I should be able to get that scavenging back, which would restore the power. It will take some fabrication, but I think it could be done.

Once again, I do apologize. I need to now start working this idea so that it CAN be worked out. I refuse to quit.
 
With the help of my roommate and his gf, was finally able to maneuver everything around and get the old one off. I will live with the reduced power until I can have fabricated a crossover styled after the stock setup. Will take welding on appropriate pieces, but I feel it can be done.

Come hell or high water, I WILL make it all work in the end.
 
I took the 85 apart, went from this..........................................to this . Its still a roller Kyle , and a lot lighter :biglaugh:
Like I said if I was doing better right now I would buy the frame & engine the rest of the stuff I could piece together. As long as I could keep the frame & engine together 211 would be back on the road in bone stock form. Actually it would probably be a garage queen or living room piece.LOL
 
"Biker dash," Ok, all's good on this end. Thank-you for your explanation. I am willing to assist in any way I can. I am not a fabrication specialist, but I bet you could get some ideas from those who are here. I have had some good results with a local muffler shop which has helped me with some pipe bending, end expansion, and material. Make friends, see if they can do something for you when the big jobs aren't there, and maybe be able to leave your bike for them to fit stuff when it's slow. I don't know if I would do that if my ride wasn't insured, f.y.i. (leaving it).
 
The individual cobra mufflers themselves aren't going to rob too much flow. The problem is many fold.

First, as has been noted you lose scavenging. The hot gasses want to go to cold. This makes them move out of the pipe on their own without having to be "pushed" out. Remember the hot air rises or moves to cold. Same principal here. No, matter how hot it is outside it's far hotter in the pipe so let's get this exhaust pulse out of the pipe.

Second, even if you were to merge two of the pipes together prior to the individual mufflers you'd have a small bottle next at the original junction point for the stock connections. You could cut this off and enlarge this junction to help with flow. You will also need to enlarge the primary pipe work which means replacing all the stock pipes which aren't normally required with the Cobra's. So, now you're needing a full system. At best if you could join the two sets of mufflers together at the junction point of the pipes this would help but maybe only bring the hp back to the stock power level (which is better then losing power).

The Cobra's are 4-4. Meaning 4 pipes into 4 mufflers. Many other systems are 4-2. Meaning 4 pipes into 2 mufflers. These join 2 exhaust pulses into 1 (on each side) and then out the muffler. Depending on how this is done will depend on what power you make. With slip-on systems like the supertrapps/kerker slip-ons and others you make that join right before the muffler and also retain the stock restrictive pipe work. This only gives you the same amount of effective flow that the stock system had and thus the same power level. FYI, we've made mid 130's rwhp with a 1300 engine with the stock mufflers (and stock venture pistons in the engine)

When you get a full header (4-2) this changes the primary tubing size to allow for more flow. The merge is also done a little sooner in the system then just at the mufflers. This also helps scavenging and thus these systems make more power. This would be the full systems like Marks, Holeshot, and UFO (as well as a few others).

The 4-1 systems join all 4 pipes into one muffler. These systems are pretty much not made anymore. The old original Hindle (a big tube and small tube were made) was one of the very few made like this. They made excellent power from the scavanging they were able to provide.

The 4-2-1 like the kerker is a bit more unique. These came from the 4 cylinders (tubes) into a two mergers then those two merged into 1 pipe/muffler. Sort of the best of both worlds here. Scavenging helping scavenging. This also let them keep more ground clearance that was lost of the 4-1 systems. Still the power made by these wasn't just any big jump over the other 4-2 systems.

You will want to try and make your Hybrid Cobra into a 4-2-4 system. This would get the scavenging needed but the look you want. If you can enlarge the primary pipe work and enlarge the junctions of the mufflers this would be better.

Ask Vmax1260 (George) of a 4-2-1-2 system we sent him. This was a custom request made by Marks. You could request that he make you a setup to use the 4-2-4 system using those cobra mufflers. Not sure what the cost would be?

Sean
 
The individual cobra mufflers themselves aren't going to rob too much flow. The problem is many fold.

First, as has been noted you lose scavenging. The hot gasses want to go to cold. This makes them move out of the pipe on their own without having to be "pushed" out. Remember the hot air rises or moves to cold. Same principal here. No, matter how hot it is outside it's far hotter in the pipe so let's get this exhaust pulse out of the pipe.

Second, even if you were to merge two of the pipes together prior to the individual mufflers you'd have a small bottle next at the original junction point for the stock connections. You could cut this off and enlarge this junction to help with flow. You will also need to enlarge the primary pipe work which means replacing all the stock pipes which aren't normally required with the Cobra's. So, now you're needing a full system. At best if you could join the two sets of mufflers together at the junction point of the pipes this would help but maybe only bring the hp back to the stock power level (which is better then losing power).

The Cobra's are 4-4. Meaning 4 pipes into 4 mufflers. Many other systems are 4-2. Meaning 4 pipes into 2 mufflers. These join 2 exhaust pulses into 1 (on each side) and then out the muffler. Depending on how this is done will depend on what power you make. With slip-on systems like the supertrapps/kerker slip-ons and others you make that join right before the muffler and also retain the stock restrictive pipe work. This only gives you the same amount of effective flow that the stock system had and thus the same power level. FYI, we've made mid 130's rwhp with a 1300 engine with the stock mufflers (and stock venture pistons in the engine)

When you get a full header (4-2) this changes the primary tubing size to allow for more flow. The merge is also done a little sooner in the system then just at the mufflers. This also helps scavenging and thus these systems make more power. This would be the full systems like Marks, Holeshot, and UFO (as well as a few others).

The 4-1 systems join all 4 pipes into one muffler. These systems are pretty much not made anymore. The old original Hindle (a big tube and small tube were made) was one of the very few made like this. They made excellent power from the scavanging they were able to provide.

The 4-2-1 like the kerker is a bit more unique. These came from the 4 cylinders (tubes) into a two mergers then those two merged into 1 pipe/muffler. Sort of the best of both worlds here. Scavenging helping scavenging. This also let them keep more ground clearance that was lost of the 4-1 systems. Still the power made by these wasn't just any big jump over the other 4-2 systems.

You will want to try and make your Hybrid Cobra into a 4-2-4 system. This would get the scavenging needed but the look you want. If you can enlarge the primary pipe work and enlarge the junctions of the mufflers this would be better.

Ask Vmax1260 (George) of a 4-2-1-2 system we sent him. This was a custom request made by Marks. You could request that he make you a setup to use the 4-2-4 system using those cobra mufflers. Not sure what the cost would be?

Sean

Ok, since the stock system looks to be a 4-1-2 setup, (four headers connecting into a sizable collector, it gave me an idea that I was wondering would help in this.

Right behind where the Cobra pipes merge with the stock headers, 4 sidepipes could be cut and welded in to connect with a crossover. I was thinking either a box collector style of volume roughly equal to the big collector on the stock exhaust, that or an X-pipe.

Either way would have all four pipes interconnected. Would this help with the scavenging? Also, I would definitely want to enlarge the junction of the headers to the slip-ons. One other thing I thought of is getting the stock header pipes coated. Do those coatings actually work at retaining heat within the exhaust, and would that help as well with scavenging?
 
Put on silver decals, now it's no longer without emblems. will post pics later :)
Had some great comments about it. Even from one bloke that said "sweet bike man. I've never heard of a Yamaha Archangel, Is it a 2014? It kind of reminds me of a Vmax."



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Put on silver decals, now it's no longer. will post pics later :)
Had some great comments about it. Even from one bloke that said "sweet bike man. I've never heard of a Yamaha Archangel, Is it a 2014? It kind of reminds me of a Vmax."
That's awesome. :punk:
 
Here is some pictures. It's weird, they don't photograph well. I'm going to have to play with the cameras settings. But on the bike they're a brushed aluminum color, not white as they appear. They match the scoop grills, radiator cover, and other brushed bits perfectly. But, when light gets on them they reflect.

The tank emblem is the tribal one that has been around for a while. The Vmx is the vmax font with the 12 and "Archangel" in archangel.ttf font. :)

4rf9.jpg


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