Kawasaki GPX750

Do You Remember The Kawasaki GPX750R

GPX750Here at Classic-Motorbikes.net, it’s not just the chart-toppers and yardstick bikes that we like to talk about – we love reminding you about the bikes that didn’t quite make it that big…

What was it then?
According to Kawasaki, the GPX was the future…OK, so it had already given us a smaller GPz750R version of the 900R in 1985… but this was going to really set a light under the faired 750 crowd.  It was plenty quick, good enough in fact to crack 150mph and comfy enough to do 150 miles in one stint: that was handy as that was the tank range. The GPX range also almost became as big a family as the likes of the VFRs and GSX-Rs. We say ‘almost’. The GPX600R was a real treat, being both capable and a good all-round bike, while the GPX250R was a twin-cylinder machine which was a cute bike to ride, but… Well, it seemed that none of the family seemed to catch on that much, at least not the elder and bigger brother.

Why not?
Well, possibly because Kawasaki had a fair few 750s in its range back in the mid-1980s – let alone when you think the GPX had to compete against the opposition, too. The big K had the GPz750 Uni-Trak (a venerable and trusty 750) with its air-cooled engine wrapped up smartly in the GPz trademark red paintwork, the shaft-drive GT750 (fave of couriers and a big seller.) Then there was the GPz750R, which was confusing as it was simply a smaller CC (but identical otherwise) GPz900R but with less oomph, and then there was the mighty GPz750 Turbo. Crazy-as…

Please explain the odd looks!
GPX EngineRemember the times: these were the early days of aerodynamics on motorcycles and full-fairings hadn’t been around for long. Any mock ups would be evaluated in a wind-tunnel to get everything just-so. Don’t forget this was around the time of the original ‘jelly-mould’ Honda CBR600/1000s… Thankfully what quirky bodywork the GPX did have, was clothed in restrained and attractive paint schemes…

Was the bike any good?
It was a Kawasaki, so it was plenty fast but also had great handling and road manners. Unlike Suzuki’s GSX-R750 its power wasn’t stacked high up the rev range so it was more flexible out on the road too. It was also very comfortable. While the engine was the star of the show, the chassis was less edgy: steel
frame and mismatched wheel sizes didn’t really help when people tried
to race them though. However, in World Superbikes Aussie Rob ‘Syph’ Philllis did OK on one, but this was a road bike through and through and on the road it was a good package, even two-up.

What went wrong with them?
Some camshafts failed, like the early GPz900Rs it appears oil starvation when starting from cold could quickly attack the lobe surfaces, Kawasaki’s inability to build a choke set-up that didn’t send the revs through 6000 rpm from hitting the starter button probably didn’t help matters. Exhausts also rotted quicker than fallen apples not picked up by foreign workers post Brexit…

Why didn’t it last?
Kawasaki GPXWell, we’ve covered the fact that it was born into an extended family of Kawasaki four-cylinder 750s. It came along in 1986 and was pretty much gone by 1988, although some could be bought for a while after into 1989. Kawasaki replaced it with the all-new and much racier ZXR750 H1. The ZXR and the GPX did share many engine components, but the ZXR was a much sharper looker, ironic then that the GPX750R was actually both faster than and lighter than its much sportier replacement. How weird is that?

Why would I want one?
We at CB-NET reckon that (issues aside) it’s still a good all-round road bike… and it’s very cheap…

What do they cost?
Prices for used GPX750Rs have always been low compared with its rivals but the trick is to find one… as it only had a two-year lifespan. That said, when available, you can get a good one for around a grand and a ‘work in progress’ for half that. While you’re here, can we suggest you look at little brother, the GPX600R? OK, so you’re looking at the same prices, rising to under £2000 for a really good one (they were deleted and re-introduced in the mid-1990s) but this means many more are available…

Kawasaki GPX750R 1986-1988
Price when new: £4299 (1989)
Price now: £500- £1000
Engine: Liquid cooled 16 valve DOHC
Power: 100BHP claimed..
Weight: 195kg (dry)
Wheelbase: 1460mm

For: Comfortable and plenty quick.

Against: Quirky looks and some reliability issues…