de cat

[cOoTeR]

This is a great find Keith. Wonder how this would compare to the fitting of the 2011-2015 ZX10R oem headers. I would think that Kawasaki would have optimized the stock headers to work with this particular motor including the supercharger. I know factories spend enormous amounts to give the best performance possible with stock pipes but are limited by emissions and sound level requirements. I'm running a Yosh Alpha slip-on, Sprint filter and Vcyclenut flash so I know it would require a reflash from David but wonder if the flash he has developed for the ZX10 header kit he sells would be right for this configuration? The only real benefit I see with the ZX10 header over this would be that they are Titanium and would be a few lbs lighter.

Anyone know what the header info is on the H2?

Maybe that'd be a 'tuned' for the HP and good set for the SX's.

The exhaust ports are different between the 2 bikes so it won't work.

Cooter, thanks. Are you aware of the rest of the header after the port connection? I'm wondering about the flow differences between those two (H2/H2SX) headers.

Also, what'd you think of a stock can, flies fixed open, and no cat? I'm wondering/thinking that the stock can, with flies fixed open, would have only a little shave of HP/TQ from an after market can, not counting the cat.

The primary tubes on the h2 are more oval shaped the h2 sx is more of a circle shape. After that it doesn't matter to me because unless you are going to change heads the design won't work with the other bike regardless of which flows better.

I'm not a fan of stock cans on exhausts systems that have been altered. I haven't heard it on the H2SX but the bikes that I've heard with that setup have all had a hollow/echo sound that is loud and horrible. It sounds fluttery to me. I'd have to look at the inside of a stock can but I don't think there would be a huge relative power difference in using one but it is a heavy can and looks like crap.

[PhukDD]

Apparently I did not ride fast enough when I data logged for the fueling adjustments. Goes flat around 135mph....got the data now...we will fix this.

[Prof J]

https://www.ebay.co.uk/itm/Kawasaki-H2- ... Sw1YRcoIjO
just seen this on ebay anyone on here removed the ugly cat box and fit one of these , certainly looks much better , and would improve the sound , any pros cons

If we had the dimensions a muffler shop could fab one up, cheap. Or some of us could fab one up.

[Drnick]

I’m in south Florida, Blaise cycle, did the dyno run, and no, I didn’t have a dyno before the decat mod, but I was told that
Most stock H2SX’s run about 170 hp + or - 2hp.

[mrjim]

What would be the problems encountered if you left the cat on and the exhaust valve on? I had a muffler shop mount a Muzzy slip on to stock muffler box. I lost 10lbs. and the sound is deeper and more throaty. If you just cut out the muffler box and replace it with another exhaust mid pipe ,still keeping the exhaust valve ,you would drop another 10lbs. and still keep cat and stock 02 sensor. I"m thinking of this before a Vcyclenut flash. Comments?

[Prof J]

What would be the problems encountered if you left the cat on and the exhaust valve on? I had a muffler shop mount a Muzzy slip on to stock muffler box. I lost 10lbs. and the sound is deeper and more throaty. If you just cut out the muffler box and replace it with another exhaust mid pipe ,still keeping the exhaust valve ,you would drop another 10lbs. and still keep cat and stock 02 sensor. I"m thinking of this before a Vcyclenut flash. Comments?

I'm not sure about the "problems", but I do wonder about the decrement of the CAT to the overall system performance. Old news, but a 10 years ago a very good and busy custom tuner told me that CAT's only decreased power by about .2 to .5 HP.

I have always questioned this, and I have not seen and dyno runs just comparing pre and post CAT tunes. Maybe there is more recent info? If that is accurate, however, more the 'reason' to leave the CAT's alone/in.

Secondly, why are you considering leaving the exhaust valve in (by this do you mean the in-built exhaust butterfly)?

Third, if you are going for a flash tune, have you considered the difference between using a P08 filter 'tune' vs a P08 F1 filter tune? There is a 300 percent difference in manufacturer reported CFM for the Sprint P08 F1 filter, over the P08 filter, which if accurate, ought to be very beneficial performance wise.

I have to believe, until someone demonstrably and repeatedly dyno demonstrates 'no difference/no meaningful difference', that the F1 filter ought to be the filter to use, and perhaps add 8, maybe 10 HP on a custom tune (?).

[mrjim]

Prof J,I did not want the extra work of removing cables and electric motor. The exhaust butterfly also retains bottom end grunt. Also I wanted to keep stock O2 sensor if possible.

[Prof J]

Prof J,I did not want the extra work of removing cables and electric motor. The exhaust butterfly also retains bottom end grunt. Also I wanted to keep stock O2 sensor if possible.

mrjim,

I understand your thoughts about the flies and lower end grunt, but I think, at least a decade ago that was not supported by actual custom dyno tunes.

And I thought I read, locally, and for recent times, that the low-end grunt (TQ) loss by removal of the exhaust flies, was not factually supported by dyno results.

Perhaps someone with more familiarity or better memory will add their insights?

[vcyclenut]

a dyno is not going to show what the exhaust valve does on this bike as it remains open during full throttle runs, it closes down at part throttle I honestly could feel zero difference when I did testing with the stock pipe from it being set up normal and forcing it to be open all the time

with modern bikes you have to be careful about using results from different bikes and assuming the same will happen with another bike

but in general yes exhaust valves are now used to help with noise emission testing

[Pystones73]

Alguien ha taladrado la primera pared de catalizador desde la válvula de escape para ver si se gana algo de sonido??? Ya que veo según esquema que tiene dos paredes más, desde la válvula de escape se puede acceder con una broca grande y eliminar esa pared de catalizador.

Alguna experiencia?