Kawasaki ZXR750 Race Bike

Kawasaki ZXR-based Racer


Remember Karl Webster and friends building a Kawasaki ZXR-based racer in less than a week? We continue the amazing story of this old, cheap bike!

It’s fair to say there’s something about Phillip Island…. Or ‘The Island’ as we call it.Kawasaki ZXR750 Race Bike

When I say that, ‘The Island’ I’m talking about isn’t the one that draws in the bus-loads of Japanese tourists who come at night to watch the Penguins parade up the beach. Oh no, ‘The Island’ I come back for represents the sound of a screaming Japanese classic motorcycle in all its fury down the main straight before throwing itself into turn one. Just watching and hearing such a thing sends shivers down your spine and stands the hair up on the back of your neck. It’s the beautiful backdrop of the southern ocean along with the undulating track with its wide Tarmac and awesome corners that make this one of the best bike places to be.

So many events are held at The Island but for me the AMCN (Australian Motor Cycle News) International Island Classic is the perfect one, as it covers bikes that I remember admiring and even owning a couple of the road versions back in the day. Yes, I go to MotoGP and World Superbikes here, but the International Island Classic is the event I love the most.

Part of the attraction is that the classes cover bikes from before the First World War to 1990. So, whoever you are and whatever spins your crank, you can buy something from an era, keep improving it and keep coming back time and again.

Kawasaki ZXR750 RacerAnd they do – riders from the UK, New Zealand, the USA, Japan and all over Europe come here for the fun. In fact, the one we first attended was the 22nd event of its kind – so that’s not too shabby.  The (past) and present cream of GP racers, WSB racers and road racers are represented: Jeremy McWilliams, John McGuinness, Cameron Donald, Shawn Giles and Aussie newcomer to the event Jed Metcher are just a few of the names.

And then in 2015 there was us! You’ll recall our Kawasaki ZXR750 H2 which we got ready (just) thanks to the hard work of my partner in crime John Wilkinson. Being partial to a Kwaka and having owned and raced the first ZXR in its day in this neck of the woods, John took a liking to the old H2 and was formulating a plan to give it a second chance. His son Mark had not long returned from racing in the UK, and having missed the entry the previous year (you’ll remember instead we raced in the WSB support event), I simply handed over the ZXR, in effect making it our Project Race ZXR! The way I thought, when I got it back, it’d be well-ragged, but with John in charge of sorting it – it would also be a pretty handy track bike that I’d be getting back!

So just to remind you all… this was a Kawasaki ZXR750 H2 with 82,000km on her. The project was to prove that a talented rider (Mark) could achieve something special on a very inexpensive motorcycle put together by his talented dad. And some bikes out there had six-figure price tags, let me tell you. The idea was that we should start at the bottom as far as development goes and gradually throw in some more mods and see what results we could get.

Kawasaki ZXR750 race bike in the pitsBefore pulling it down to a bare frame, the plan was a basic rebuild including pistons, cams, valves and a port job, but two weeks out from Christmas and with the event a month away, we realised that obtaining these parts was a lot harder than just jumping on the net and ordering them. With this realization, we decided to still run the tired engine with only a port job by John, but with a nice set of 41mm Keihin flat-slides and custom made headers by Ken from Megacycle in Melbourne (our friendly exhaust guru.) This would be mated to a Muzzy muffler (period piece of course) and chassis-wise we would go for re-valved front forks, and a Wilbers shock – both set up for Mark by Trevor Manley.

The year before at the WSB event, Mark qualified second in the wet on the bike ahead of the legendary Rob ‘Syph’ Phillis. It must have been hard for ‘Mr Superbike’ to swallow being beaten by a fairly stock version of your 1990 superbike! Of course in the dry it was a different proposition and the power counted – Mark managed around 4th-5th placings, but these were still respectable! This year we skipped Thursday practice (it costs another $180 and we are tight Aussie bastards) we only had one set of slicks and one set of wets anyways. Despite being rusty Mark qualified fifth with a slipping clutch. Some talent! Sadly John said he couldn’t fix the clutch as we didn’t have one. I was at home so I was chatting to them on the phone – but the dejection was palpable both at home with me and from the Island.

ZXR750 race bikeWith my working week at an end it was time for me to head to Phillip Island. I figured I’d try and get a clutch and take it with me – but our local Kwak dealer Elliot Bros said they didn’t have one. What they did do was hit the internet and see if anyone local to the Island in Melbourne had one. I couldn’t let the boys down, so I chanced it with a call to Kawasaki head office in Australia. They tracked down a clutch in a shop in the suburbs of Melbourne that was wrongly ordered but sitting in oil looking for a home. Apparently it’s the same clutch as in the KLR650 – we got the thing ordered and began our journey to collect it and meet the boys. As the dealer would be closed when we arrived they hid it under a 44-gallon drum outside the shop! Cheers guys!

Making the call to John was fun. They were wrestling with the bike trying to make do and mend but when I told them I’d got a clutch John said simply ‘bullshit’ as he didn’t believe me that I’d tracked one down. Mark later told me that when John put the phone down he said: “Karl’s done it again… the tin-arse has found the only clutch in the State and is on his way.” I think they were in shock…

When at Phillip Island we stay at Kev Martin’s place. He’s a guy with OCD about cleaning bikes and one of our best mates. He and his wife go out of their way to make us feel welcome. In Kev’s shed the lights were on as I arrived and John had the bike ready to receive the new clutch. Now, John’s not an emotional bugger, but I swear he actually hugged me when I handed over the clutch. With the weekend still ahead of us – anything was possible! With the bike together and sounding sweet (despite the huge amount of klicks on the thing) a sticking clutch saw us remove it again. The basket itself was worn and had formed grooves that the new plates were sticking to. Painstaking work followed, with John patiently filing microns from both the basket and plates. Soon the ZXR was ready for action.

ZXR750 race readySaturday dawned – race day with a first event for us at 11am. On the grid was a fair amount of talent and dollars. In first and second on the grid were about $200,000 worth of ex-factory Honda RC30s, complete with former champ Malcolm Campbell and his son. Third on the grid was the-then current west-Australian classic champ on a 1990 Suzuki GSX-R750 with all the bits on it – had to admit that it looked the horn! We knew Mark had his work cut out here, as the RC30s were in a different league and almost three seconds faster than the rest, but we felt it was just the right time for some giant V4 killing…

The green light goes out and Mark has a poor start, but battles back to fourth position at the flag. Not bad with a clutch that was ‘bedding-in .’ With more than 30 bikes out there from all of Australia, our humble ZXR was earning respect from riders and spectators alike! Many came to ask what was under the bodywork – they were shocked to know how little work had been done to the 80,000km ROAD bike!

In between races OCD Kev cleaned the bike up a treat – so it looked the business. Race two was the same result – but Mark was much closer to third and that elusive pot! After the battle the final podium place finisher came to see us and ask about the bike – he was blown away that Mark was doing so much with so little!

Sunday dawned and while Greg and I had breakfast in bed at OCD Kev’s (not together, you filthy mongrels) Mark and John were at the track plotting a way to get more from the Green Meanie. John figured that he should lift the needles in the Keihins about two notches to improve power delivery a little. Again in race three the Hondas are away and Mark is dicing for third once more, this time with the trick GSX-R. The carb work had done its job, as Mark came out of the last corner in third – only to be slipstreamed over the line! Fourth again…The final race played out in a similar vein, giving Mark a very respectable fourth place overall in the Formula 750 class and a four-second improvement over the previous year’s best lap time!

Philip Island Classic Bike MeetingOK, so we didn’t get an elusive trophy, but we were quicker and – with our plans to be at that March’s Barry Sheene Festival of Speed, planned upgrades to the ZXR (bottom-end rebuild, undercut gears, a programmable ignition supplied by Craig from CM Motorcycles) meant we should have a bike (and a rider in Mark) that would be hard to beat. We just needed more donks from that tired old inline four to ensure our first silverware in the classes we would be racing in.

It’s not all about the racing either – it’s the bikes on show at these events. Check out our pictures. The whole event is impressive and they really put on a spectacle with bikes from all  the various eras. The other thing I love about the classic is the pits are open to all and trust is given for people to walk freely through the pit garages and ask questions or take photos of the bikes or even meet and chat to the big-name riders. And if you’re a metal fetishist, you’ll see the very best on display from Pommies like Harris Engineering, to McIntosh from New Zealand and our own T-Rex from Melbourne!

So what about our humble ZXR? Well, we will ‘keep on, keeping on’. Slowly moving forward with negligible budget but a thirst for results, we have a great bike, rider and chief technician.