Kawasaki ZX-4R

[KungFooBob]

I weighed my 98 Blade on some car corner scales at a trackday, with circa 5l of fuel on board it was 186kg, iirc.

I weighed my 620SSie racebike on the pits/scrutineering scale at Oulton, it was 177kg with a similar fuel load.

One had 120bhp, the other 65.

I'm not sure what point I'm trying to make here.

[SSS]

@kungfoobob I think your agreeing that the ZX4R(R) needs to go on a diet with its lardy 189kg in comparison to bikes old and new... wonder if its the steel frame which does it.

[KungFooBob]

My 620 was pretty stripped back, no lights, race bodywork, alloy swingarm off the 900 no ABS, single exhaust, etc... Most of the weight was in the steel tank and the air-cooled engine.

They only way to make it lighter and stay within the rules was an alloy tank, the class lower limit was 165kg, but I don't think anyone was really close.

[Bigjawa]

I had an old 1980s FZ600 that had a steel frame, steel tank and a 4cyl aircooled engine, they were 186kg dry.

They've just built a screamer of an engine and stuck it in a lardy chassis. I wonder how long they'll last as you'll need to rev the shit out of it to get it to move.

[KungFooBob]

It turns out that if you want a light semi powerful bike you just need Millyard to build it for you...



Looks a bit of a handful for Foggy at the end.

[A_morti]

I had an old 1980s FZ600 that had a steel frame, steel tank and a 4cyl aircooled engine, they were 186kg dry.

They've just built a screamer of an engine and stuck it in a lardy chassis. I wonder how long they'll last as you'll need to rev the shit out of it to get it to move.

This young man makes the perfect point: the 75hp engine could make 92hp, but it's good that it doesn't.



I'm sure it could also weigh less than 188kg fully fuelled, but what would it cost then?

When we look back on the 400s of old (a ZXR400L weighed 177kg wet), we need to remember they came from a very special mix of circumstances where an unusually large number of people found themselves with litre bike money and a will to ride a motorcycle, but could only legally buy a 400. By a galactic fluke, they then all sold them dirt cheap 10 years later when they could no longer be taxed, and many of them got on a boat for UK where even after being shipped across the world, they got sold for peanuts. That set of circumstances isn't coming around again any time soon.

Kawasaki DGAF about the UK market, rather the driving market for this bike is aspirational SE Asians. They may have big money for India or Indonesia, but they don't have aluminum frame money and even if they did, they'd probably rather get an extra USB-C port.

[A_morti]

Yeah. 188kg.

My RVF400 is about 25kg lighter.... and it could be considered heavy.

Apples and oranges, amigo.

ZX-4R is quoted as 188kg wet: that's ready to go with a full 15 litre tank of fuel.
RVF400 is quoted at 165kg dry: that's no fuel, no oil, no coolant, no water in the battery, no brake fluid, no fork oil, no nothing. Curb weight is what counts and it's hard to find a solid source on, but mostly quoted somewhere around 183kg. No idea if that's with a full 16 litre tank or x litres only.

So... 5kg difference. Maybe. I bet if you ditched the ZX-4R's catalyst you'd be level pegging, and if you deleted the ABS too then you'd already be under. But turns out we want/need those things on a modern bike.

[Rockburner]

I had an old 1980s FZ600 that had a steel frame, steel tank and a 4cyl aircooled engine, they were 186kg dry.

They've just built a screamer of an engine and stuck it in a lardy chassis. I wonder how long they'll last as you'll need to rev the shit out of it to get it to move.

This young man makes the perfect point: the 75hp engine could make 92hp, but it's good that it doesn't.



I'm sure it could also weigh less than 188kg fully fuelled, but what would it cost then?

When we look back on the 400s of old (a ZXR400L weighed 177kg wet), we need to remember they came from a very special mix of circumstances where an unusually large number of people found themselves with litre bike money and a will to ride a motorcycle, but could only legally buy a 400. By a galactic fluke, they then all sold them dirt cheap 10 years later when they could no longer be taxed, and many of them got on a boat for UK where even after being shipped across the world, they got sold for peanuts. That set of circumstances isn't coming around again any time soon.

Kawasaki DGAF about the UK market, rather the driving market for this bike is aspirational SE Asians. They may have big money for India or Indonesia, but they don't have aluminum frame money and even if they did, they'd probably rather get an extra USB-C port.

The ZXR400 was an official UK import from Kawasaki for over 10 years. IIRC the CBR was a official import for 1 or 2 years, similarly the RVF. The FZR and the GSXR 400s were either never official imports, or only for a year at a time. The ZXR400L was "not quite but nearly" state of the art when it was launched, (it didn't have all the adjustable suspension that the 7R had, iirc); Similar for the RVF.

This new ZX4R is only "state of the art" in the factb that it's new and made to be as frugal as possible, albeit in an IL4.

[A_morti]

The ZXR400 was an official UK import from Kawasaki for over 10 years. IIRC the CBR was a official import for 1 or 2 years, similarly the RVF. The FZR and the GSXR 400s were either never official imports, or only for a year at a time. The ZXR400L was "not quite but nearly" state of the art when it was launched, (it didn't have all the adjustable suspension that the 7R had, iirc); Similar for the RVF.

This new ZX4R is only "state of the art" in the factb that it's new and made to be as frugal as possible, albeit in an IL4.

The CBR was never imported, but the VFR was. The ZXR was imported officially, but let's not kid ourselves and think they cared about UK when designing it, same for the VFR. They sent us steel framed CBR600s, because that's what the market wanted and would pay for.

Even as a budget bike with a fancy/uncommon engine configuration, it's +10hp (against a fast old 400) despite catalysts, and only +11kg from a light old 400 (+5kg from a heavy old one), despite ABS, catalysts, a steel frame, etc.

Since you mention a ZX7r. What comparison could you make both now, and back in the early 90s? Well, let's say 400 supersport versus top of the range supersport.
A ZX10R now is £17.5k, a ZX4R is £8.7k, so just about half the money.
I have no clue what the UK import 400's cost new back then, when compared with a 1994 ZX9R at £8.1k. A 600 bandit was £4k in 1996, and I bet it was more than that. The relative rarity of UK import ZXR400's compared to ZX-9s also suggests it wasn't half the price as nowadays.

In the end - they did a decent job on balancing weight/power/price, where maybe you only get to pick two.

[Bigjawa]

The "official" NC30 was over 6k back in 1992. It was about 2k more than the ZXR. I paid £1500 for my grey, sold as seen, straight from the shipping container.

The FZR had a cheaper model and an RR version, they were dear too. Both the NC and FZR were very common in SS400 racing over here.

[Le_Fromage_Grande]

Yamaha UK sold FZR400s as official models, both RRs and SPs, a JDM FZR400RR has a 3TJ prefix, a UK has a 4DX prefix, the SP is a 4DX2, I think they cost about the same as a YZF750

[KungFooBob]

I had a 4DX. Different clock faces to the 3TJ, obviously.

The 4DX also had the rear light, indicators and mirrors from the UK model FZR600/1000.

[Le_Fromage_Grande]

I had a 3TJ, it was restricted to 180kph by some contacts in the speedo, if you used a speedo corrector, it was restricted to 180mph, but I also bypassed the rev limiter on mine, did about 20 track days on it and sold it for what I paid for it.

[KungFooBob]

I might have mentioned it before, but I loved mine... N880 DWF.

My mate called it Nobbo Dwarf.

[slowhare]

It turns out that if you want a light semi powerful bike you just need Millyard to build it for you...



Looks a bit of a handful for Foggy at the end.

That man is amazing, would love to meet him and try one of his wife’s cupcakes.

[Bustaspoke]

A lot of those ZXR400's are going to the BSB paddock next year,or will the RR version be very different to the road bike?

Kawasaki British Superteen Championship:

"In association with Kawasaki UK a high level promoted championship with manufacturer presence and support and importantly contained budget and technical controls. The machine to be used is the Kawasaki Ninja ZX-4RR which will offer a higher standard of competition material. Rider eligibility is a minimum age of 15 years old on 1st April 2024 and a maximum of 20 years old on 1st April 2024. Riders must have a minimum of a Clubman licence."

[Yorick]

Kids at 15 should be on Moto3 type bikes. Not heavy proddy bikes.

[Bustaspoke]

There's not enough money in racing over here so they're forced down the proddy route

[Le_Fromage_Grande]

Dunno what it's like now, but 35 years ago TZs were cheaper to run than proddie bikes if you were a crasher.

[Yorick]

Dunno what it's like now, but 35 years ago TZs were cheaper to run than proddie bikes if you were a crasher.

TZs cost thousands to run. So many engine builds.