Gen2 exhausts: blackwidow 4>2 vs delkovic 4>1 dyno.

[ottafish]

Previously I had a blackwidow 4>2 exhaust with dual yosh cf cans. Decided I wanted to go single, so out of curiosity, went for a delkovic 4>1 system and used 1 of the yosh cf cans. Both systems have been ceramic coated by the same place in the same format, both dynoed on the same dyno, both with fresh oil and filter.
The dyno is at a Suzuki shop that builds race bikes and has run race teams, so they know what their doing and all the equipment is properly maintained.

Between 4000-7500 rpm, the delkovic lost 8hp and also dropped torque. But pulled more in the upper rpm, @ >10k, before drop off. Apart from that, very similar.

So, do I want to drop 8hp to gain easy access to the chain and a cleaner looking bike?
Now I'm thinking I might try a blackwidow 4>1 and see.

 

[Hayabusa Wannabe]

It is typical character for any single output to have less torque down low but more peak flow and higher peak power. Another effect of that, torque down low is related to efficiency so the dual setup may provide more miles per gallon at cruising speeds.

You have to answer the question. If power is important to you then consider a recommendation from here for a system that produces the highest relative power among all of them (I think members recommend Brock's?) While such may make up for some of that 8 HP loss, note that the single output will still be an inherent compromise.

If you want a personal opinion, the peak numbers game is silly to me. There is no truth or goodness inherent in numbers. Also, gaining access to the left side is invaluable. A symmetric bike? When we are riding essentially racing vehicles? I never understood that. Do the single output!

 

[Bumblebee]

It is typical character for any single output to have less torque down low but more peak flow and higher peak power. Another effect of that, torque down low is related to efficiency so the dual setup may provide more miles per gallon at cruising speeds.

You have to answer the question. If power is important to you then consider a recommendation from here for a system that produces the highest relative power among all of them (I think members recommend Brock's?) While such may make up for some of that 8 HP loss, note that the single output will still be an inherent compromise.

If you want a personal opinion, the peak numbers game is silly to me. There is no truth or goodness inherent in numbers. Also, gaining access to the left side is invaluable. A symmetric bike? When we are riding essentially racing vehicles? I never understood that. Do the single output!

Symmetry is the allure of the duel system...a Ti Force system for instance is both light, power producing and looks balanced.

I have pretty much always had a single system on my bikes and I like them but there are many others who like the duel systems...

Most dyno charts I've seen don't depict a mid range power drop with a single system-perhaps our expert @Boosted Cycle Perf can shed some light on this??

 

[rubbersidedown]

Agree with @Hayabusa Wannabe,agree with 2 of 3 from @Bumblebee.
Exhaust choice is probably the #1 mod done by sportbike folk and the most important to them. Put on what you like. As HW mentioned,numbers are a joke.
In this particular case,the choice @ottafish makes is entirely up to him. If your asking for advice I would suggest picking the one you like the best based foremost on looks,weight,sound then HP numbers. 'fish you said a loss of HP from 4-75...big deal. Whats the average cruising speed...4 thou there abouts. So,yer in 5th or 6th crusing along and need to pass something on the road,the Busa has plenty of torque for that without dropping a gear. This whole "roll-on power" from 60 MPH on up is marketing drivle created by bike sellers and the magazines that test and help sell them. Loose quote from another thread..."Well the triumph rocket III is point 2 of a second faster than a Busa from 60-80 MPH...big fuggin deal. I would look at the 3 things I mentioned above and maybe take into account HP at certain RPM ranges. HW mentioned MPG...a slight consideration I suppose,but hey,it is a Busa.
MPG went right out the window for me with turbo and a slight tendency to be somewhat heavy on the throttle. I get 21 MPG on average.
As far as power in a certain range,I would trade the highs for the mids and lows all day long. The Busa has gobbs of power down low,for what? Pulling a small car out of a ditch? The mid range is fine too,even with an' approximate 4% loss as you reported.Whats ultimately important,to me anyway, is laying waste to any and all competition in all forms of racing,especially on the street when the average bozo pulls up next to you at the red light and...gives you the "Let's Go" nod.
I don't agree with Bumble that 4-1 exhausts typically make more power in the mids,but stand to be corrected by the experts.
I would lose most sportbike stock exhaust systems for a custom one for 3 or 4 good reasons,but not to chase 5-10 ponies. Suzuki Engineering and my personal hero Koji Yoshiura did a fine job with the Busa IMO. Busa mods can be tricky,there is always give and take. Good luck in your quest for the ultimate (I mean that) but the holy grail will be tough to find,
Rubb.

 

[Mythos]

When we are riding essentially racing vehicles? I never understood that. Do the single output!

Yep. Get used to a single, it's the race look. It's lighter and as you said, provides better easier access to the chain and sprocket not to mention opens up room for things like nitrous bottles. The only dual I know of that was said to prduce better hp than a single was a Brocks CT Dual but I'm more familiar with ZX-14 exhausts. There are apparently are some duals other the the CT Dual available for the busa.

I doubt you will feel a significant difference in power (or loss) between most exhausts. There's no question my Tsukigi Cannon on my busa feels just as peppy at low rpm as high and it's said Tsukigi is like Brocks in Japan, well respected and very race oriented.

So don't worry about it. You're not worried about racing at 4000 rpm and you're not worried about racing if you don't have a Brocks or Akrapovich anyway. Down 8 hp at 7,500 rpm would be about what, a 7% reduction from stock? You won't tell the difference between 150 hp and 142.

There's well known racing exhausts that improve performance over stock at any rpm over 3500. If you want to save money, you can mix and match but you might be better to just go with slip ons and then you have your balanced look too. Check out a Brocks dyno chart. There's a 10 hp gain at 7500 rpm, not a loss. Ask your race shop what they use. I'll bet it's not Delkevic and probably not mixing one muffler with another header/collector. But hey if you're not racing, probably it won't make a big dif. I knew a guy who welded car exhaust tips on his midpipes. It looked good, it was light and the bike was still fast and sounded great. Cost him $50.

 

[Bumblebee]

Agree with @Hayabusa Wannabe,agree with 2 of 3 from @Bumblebee.

I don't agree with Bumble that 4-1 exhausts typically make more power in the mids,but stand to be corrected by the experts.

Rubb.

Now, I didn't say they made more power but never saw a dyno chart showing they lost power...

Hopefully Rob @Boosted Cycle Perf can educate us.....

 

[ottafish]

Brands and mixing and matching doesn't really bother me that much. It's more about personal curiosity and research more than anything. This was more about making available some dyno numbers for anyone researching the two systems. Using their own cans might change things, who knows.
I've decided to stay with the single for now as it sounds better, looks good and also the access to chain and such is excellent considering I do quite a bit of long haul 2+days away in summer.
I got them to move the dyno settings for the single to map area 1 so I can easily revert back to the dual with the correct map if I want.

I'll get the print out today and see if I can get a decent pic and post.

 

[ottafish]

The red line is the original BlackWidow 4>2 system with dual Yoshi CF mufflers.
The Blue line is the Delkevic 4>2>1 system with a single Yoshi CF muffler.
---------------------------------
The Delkevic have a single link pipe between cyl 2 & 3 - same as Yoshi do
Whereas the Akrapovic headers have links between 1&2 and 3&4 which I would assume would allow better scavenging on the exhaust cycle of the stroke and maybe help eliminate the flat spot?

 

[ottafish]

Posting this here for info for anybody that is searching and it may help them. THis is not technical or anything, just my observations.

The current BlackWidow 4>2>1 headers:

They have no x-over or balance pipe between any of the primary runs. In exhaust theory, they would loose quite a bit or power and torque down low-mid range. Probably be ok in the upper end of the rev range, but who lives there all the time - I don't.

Also, the O2 bung is placed to only read from 2 cylinders, not the full set. So your basing your readings on only 2 cylinders. Hard to get a good setup if you're running a wideband sensor. I think for street use, I would pass on these. According to the response I got from BW, "These are the most advanced that we have made"
But I got no info about tuning, mapping or such, only the above response. I asked how do you run a wideband O2 sensor if you're only reading 2 cylinders - no response to that question.

Their 4>2 system was excellent and really well made. And I liked the way it was built. Great quality.
But the 4>2>1 I'm not so sure about.

 

[Sparky405]

 

[Sparky405]

I have blk widow 4 into one this is how mine is setup

 

[Mythos]

Brands and mixing and matching doesn't really bother me that much. It's more about personal curiosity and research more than anything.

If you google Gilberg ZX-14 you will find a thread on an old forum I used to visit. Gilberg did the most comprehensive layman's testing of various exhausts I ever have seen. At the time, duals were not available in aftermarket exhausts for the ZX-14 but it might be of some value. You may find a link other threads on bikeland or you may be able to search there. I don't know if the thread that comes up in the google search tells it all.

They have no x-over or balance pipe between any of the primary runs. In exhaust theory, they would loose quite a bit or power and torque down low-mid range. Probably be ok in the upper end of the rev range, but who lives there all the time - I don't.

Also, the O2 bung is placed to only read from 2 cylinders, not the full set. So your basing your readings on only 2 cylinders. Hard to get a good setup if you're running a wideband sensor. I think for street use, I would pass on these. According to the response I got from BW, "These are the most advanced that we have made"
But I got no info about tuning, mapping or such, only the above response. I asked how do you run a wideband O2 sensor if you're only reading 2 cylinders - no response to that question.

I can't remeber ever seeing balancer pipes in any full system. They use them for drag racing. They're not slow. Of course they take off at midrange or higher. If there was any serious loss of power with my full system, I sure didn't notice.

The location of that O2 sensor looks mighty suspicious. A wideband sensor might not clear the oil pan in that location either (the one I had welded on my Tsukigi does not--maybe a narrowband but not a wide). I have my O2 sensor on the collector of my ZX-14 and it is situated more to the RH side. I've been told that's ok for sampling even though it's more in the flow of the two RH pipes. It seems to have worked well with Autotune. If you really want to sample evenly, I have seen a picture of an exhaust with an O2 sensor on each head pipe. The bike also had four Power Commanders on it. The busa exhaust is situated in such a way that it's not possible to position an O2 sensor where the two pipes come together. You would need to go closer to the muffler. I had a conversation with the Bazzaz tech support guy years ago and he said that would be fine. I've heard it's not good to go too far downstream either though. You could plug the O2 bung and weld one in closer to the exhaust running the wire up near the rear shock to the hump. That was what I planned to do with mine. I'll have to ask more questions about having the O2 sensor that close to the muffler though---it would actually be right at the beginning of the muffler.

Their 4>2 system was excellent and really well made. And I liked the way it was built. Great quality.
But the 4>2>1 I'm not so sure about.

I'm not very knowlable in welding but IMO, those pipes look really heavy for an aftermarket system. If so, it probably is very sturdy but not what I would pick for a full system. The weightloss is the nicest performance improvement. It's tough to guess at weight from a photo but I would need to know that before buying. I remember hearing Brocks pipes are extremely thin and that is probably the reason the welding isn't as nice as you might hope. They sure are light though!

 

[Berlin Germany]

hmmmmm

here we have a manufacturer of 4 in 1 downpipes/collectors and fitting single mufflers
which has connecting pipes between 1&4 and 2&3 at the downpipes

their test-bench with carburator fired engines told the power was around 10-15 hp more over nearly the entire rpm-band
WITHOUT any changes at the carbs etc.
e.g. yamaha xjr 1300, fj 1200 and so on

for metric afine you´ll find the original drawing and my rebuilt version of the xjr-system as two attachements

and the entire exhaust system incl. mufflers save around 10-12 kg / 22-26 lbs
(comparable to the akrapovic 4 in 1)

and
the firing order, with 1–2–4–3, (see page 8-52 / 0C-6) is the same at all the busa as like as at the fj/xjr
so i would say the design of a (my) special 4in1 exhaust for the busa should be similar to the one for my fj 1200

little notice aside
because the downpipes of the busa have the same outside diameter as the fj 1200 (38 mm), i'm very hopeful that my idea should also fit perfectly with the busa.

i´ll figure it out sometime

 

[Berlin Germany]

hi all

what i forgott to mention (above) is that i took a 1200cc bandit akra muffler for my fj 1200cc
same cubics / same max rpm - that way the muffler is 100% fitting and works perfect.

to the gen1 :
what i found out by a phonecall with an akra dealer here in germany some weeks ago is that akra never built special mufflers for the hayabusa gen1
but they took the gsx-r 1000 mufflers (with db killer) for the 4 in 1 system at the busa gen1
as far as i know (and feel) with best results.

so i suppose the akra gsx-r 1000 "gixxer" (around ´01-´07 or so) 4 in 1 single muffler is "big" enough not to clogg/strangle the bigger busa-engine, although the busa have 30% more cubics than the "gixxer",
but nearly same max. rpm.

when ever available i´ll take a chance on a test bench with my ´00 busa and the akra (-downpipes & -muffler).
results i´ll post here - how ever the results will be

 

[ottafish]

As a further update, I've now moved to a full akra system. What a piece of art... Anyways she's at the shop getting tuned. What was interesting is going from the previous dyno runs with dual and a cheapo delkovic single system is she's now running lean in certain areas.. Better flow one would assume...

 

[Rocket Powered Grandad]

@Berlin Germany do you recall the manufacturer of the FJ1200 exhaust system that you speak of?

 

[Berlin Germany]

@Rocket Powered Grandad

by big chance i found a 4-2-1 system, cut in 6-8 pieces in ebay what i then welded new to the "form" i mounted at my race-fj 1100 see here the pics and description.

and here the drawing of the "Schuele" exhaust.

goog luck with your rebuild

 

[Rocket Powered Grandad]

@Rocket Powered Grandad

by big chance i found a 4-2-1 system, cut in 6-8 pieces in ebay what i then welded new to the "form" i mounted at my race-fj 1100 see here the pics and description.

and here the drawing of the "Schuele" exhaust.

goog luck with your rebuild

Thank you.

 

[Berlin Germany]

@Rocket Powered Grandad

what i forgot but never tested / measured - eventually the hayabusa gen1/2 akrapovic exhaust manifold system could fit with only a few little changes, because plugged in and therefore partially rotatable.
its dia is as far as i remember the same like at the xjr/fj

the 4 retaining clamps (on the head) may have to be reworked or reshaped new because the distance between the retaining bolts is different:
fj/xjr - ~ 67mm / hayabusa ~ 60.5mm

and not to forget the 2 interference tube from 1to4 and 2to3 at "schuele´s" (see drawing above) in nearly the same dia (35) like the downpipes (38)
the haya akra has only 1 small int.-pipe from 2to3, although i personally doubt that this small tube has any effect at all in this way.