True performance of the top 1980's bikes?

TheRoadrunner77 · Mar 4, 2019

These are what I consider the ''baddest'' Kaw sport bikes between 1980-1990:

Kawasaki GPz750: ?
Kawasaki GPz1100: 135 MPH
Kawasaki GPz750 Turbo: 148 MPH
Kawasaki GPZ900R: 151-158 MPH
Kawasaki GPZ1000RX: ?
Kawasaki ZX-10 Tomcat: 167 MPH
Kawasaki ZX-11: 176 MPH

All of these speeds are taken from Wikipedia.

The first thing that strikes me as odd is how the GPz1100 couldn't manage more than 135 MPH, something even unfaired bike with much less power in the 1970's could supposedly hit? Meanwhile the Turbo could almost match the GPZ900R both in top speed and acceleration.

I'm a big fan of the GPZ900R (One of my favourite bikes) and I've seen all types of weird performance figures for it. Does a 0-100 MPH in 7 seconds sound plausible for the bike? A McLaren F1 does 0-100 MPH in 6.3 seconds, could the 900R really challenge that thing to 100 or in the quarter mile?

If you look at most road tests they got an 11-ish second or slower 1/4 time with trap speeds ranging from 112 to 125 MPH. Top speeds are also pretty puzzling because some tests with a great quarter mile only managed a top speed of 140 MPH or less without the gearing limiting top speed, while some tests with pretty bad quarter mile trap speeds hit 155 MPH flat out.

The Tomcat and ZX-11 speeds seem pretty believeable to me, with the improved aerodynamics and increased power, I've seen some tests of the ZX-11 get up to 179 MPH. Primarily some tests by a magazine called ''Motosprint'' that seems to be in Spanish or Italian, they always have REALLY good performance figures (Almost unbeliveable sometimes), however I can't find out much about them nowadays.

Anyone have some insight on this? I'm guessing you guys have some more experience with these older (and cooler than modern) bikes.

kawpaul · Mar 16, 2019

The top speed of the GPz 750 was 136 MPH.
I like this site better than wiki.
https://www.motorcyclespecs.co.za/

That site btw lists the 1982 GPz 1100 as 108 HP with a quarter time of 11.5 and a top speed of 137 but the 1983 GPz 1100 as 120 HP and a quarter of 11 flat but no listing for top speed.

davidr1963 · Mar 16, 2019

The Gpz1100 A models in the Uk were supposedly tested at 150mph.

Gyesdad · Mar 23, 2019

As I remember back then, Kawasaki had reputation for their launch and press bikes being better performers than the production bikes. Didn't stop them selling by the bucket load though..
I think the 1000RX was rated at 160mph and was supposed to be the replacement for the 900R. It was short lived (2/3 years I think) whereas the 900R sold for years in various countries around the world. I think the last model was an A16!
As David says, the 1983 GPz1100 Unitrak was supposedly tested at 150mph, and each of the above bikes except the GPz750 were reputedly the world's fastest production motorcycle during the time of their production. In 1984 Kawasaki UK had a magazine advertisement with a picture of the 900R, GPz1100 and 750 turbo side by side, the headline being "A 450mph triple" indicating that K had 3 bikes in its range all capable of 150mph.
Rumour has it that the 750 turbo was restricted so as not to overshadow the all new GPz900R when it was launched. The turbo has a facility called "race mode" which (if I remember correctly) allows higher boost and better fuelling. The chaps on 750Turbo.com are modding these bikes and getting some serious horsepower even now.

I own at least one example of all the above with the exception of a 1000RX.

True performance of the top 1980's bikes?

Top Contributors this Month

Recommended Communities