www.zxrworld.co.uk

Been looking through what exhaust systems are available / used on the ZXR.

Having bought a BEET system of a ZX-4 which was originally for a ZXR and zimm confirming they are much the same engines I delved a little deeper

1st of for mid-range benefits nearly all performance pipes use a 4-2-1 configuration, this can be very apparent or like the BEET, Akro' , Yoshimura, Kerker and a few other a short plate in the collector.

My personal preference is a system that makes a definitive 4-2 switch, K-Factory make some of the best of this type and it is allowing the exhaust gases to combust before being thrust into the 2-1 chamber.

The "S" link pipe along with can entry/exit and header pipe diameters determine how well the engine will pick up from pre-determined rev's. a nice big bore will allow the carb's to draw in a larger volume of air/fuel. Again specialised pipes can be seen with headers that expand after exit or "S" pipes that increase in size - all these contribute to the resonance of the system and how it performs.

My Yoshimura system is fairly standard headers going into a 54mm "S" pipe with a 54mm exit on the can - I swapped the "S" pipe for a 60.5mm link pipe going into a 60.5mm can and the low end grunt was awesome - this allowed my carb's to draw in a greater air/fuel mix.

Well, i just noticed this system for the ZX-4 , it has all the traits of a very good power pipe. A true 4-2-1 set-up for your mid-range going into a big bore "S" link pipe and a big exit on the can. Perfect for FCR users

I assume the SP models run 32mm as standard ? You can also get 33mm too , now 1mm doesn't sound much (phnarr phnarr) but you'll gain another 3-4 hp over and above and a constant rise on your actual power curve.

RPM also do 4-2-1 systems but I am not sure that the bore of the pipes after the collector is as big as this :












Any thought on this?

BTW, there are two of these systems available.

Drew San.

nice looking system ..

if its been designed for the ZX4 though, dont forget that they run different cams, have smaller (30mm) carbs and a 13,500 rpm redline, so it might not work quite so well on a zxr.. might be nice on a big-bore'd bike ?

also the can will sit at a slightly odd angle (flat, not upswept) as the hanger for the can on a zx4 is the pillion peg casting, not a simple hanger that can be moved/altered and having fitted H/L/micron/scorpion and beet systems to a ZX4 i can confirm that every single one has had to have the can "pushed" down and in a bit to line up, to the point where the pillion peg gouges a chunk/dent out of the top of the can, so a zx4 system on a zxr would have the opposite problem.

nice though.. how much are they ? stainless i presume ?

Get what your saying , but with a can strap on it surely the angle can be changed? Forget any link springs - once bolted in it ain't going anywhere, there should be a photo of my bike with a short MotoGP can on it and it doesn't line up with the link springs so i didn't use them

These being race systems the ZX-4 carbs are going to have to be re-vamped or the mixture will be way to lean.

The mid pipe is definetly bigger than a BEET system for ZXR, engine spec doesn't change the resonance of a pipe and it's ability to draw in the spent gases.

However, it was a Xanthius i was thinking of when thinking about how easy to hook up - still think it is do-able when a can strap is involved and not a fixed hanger, fitted a ZRX1200 pipe on my 400 because of that reason - no hope with a fixed lug!

yeh, know what you mean ...

having re-read my post .. sorry, didnt mean it to come across so critical ..

our ZX4 had a beet system on it when we bought it, bigger main jets and a .5 mm shim under the needles sorted it, the carbs are the same as the restricted L model's but with different needles to match the airbox and no carb heaters ... shame my garage burnt down while i was out of the country, or i'd still have it .. ho hum ..

I wouldn't mind one if you could give me a rough price, they look really well made.

steve-d wrote:I wouldn't mind one if you could give me a rough price, they look really well made.

I can get one of them for a buy it now price which would make it 60,000 Yen plus shipping - sorry no idea of the weight but if we said it was 8kg then your looking at 14,400 Yen for express 3 day airmail. It is unused NOS.

Ok I will get back to you when i get paid next

i am interested in a beet system i don't suppose you could let me know of prices for new and used examples? for titanium and steel? cheers