Thursday 18 December 2014

Kawasaki GPz750

The day had been long and hard. The GPz750 silkily meandering up the coast, needing only the odd blast through the gearbox to keep the traffic in its proper place - ie eating my exhaust fumes. The Scottish border was within spitting distance and all was well with my world when the famed Scottish weather let loose with a blizzard that came out of nowhere and left me soaked through before I had a chance to don my waterproofs.

I pulled over next to the 'Welcome to Scotland' sign, got the hammer out and smashed it into a million pieces. Sarcastic bastards! The sun had suddenly disappeared and even after the storm had abated I was left a dishevelled, shivering wreck barely able to control 470lbs of suddenly disgruntled heavy metal. The Kawasaki didn't like a sudden dousing any more than I did, losing power on one or other of its four cylinders and sometimes stalling totally. It would come to life again, losing only a little forward momentum but it was damn annoying to be distracted when all my attention should've been focused on the traffic.

Anyway, the joy of the day's ride had been rudely shattered and I still had a way to go before I could hit on Glasgow's famed hospitality (yes, that was a sick attempt at humour). Coming into the city far too fast, using the wind velocity in a rather futile attempt at vaporizing the water trapped in my clothes, I suddenly had to hammer on the excellent front discs (newish discs, rebuilt calipers, Goodridge hose and EBC pads made them much better than new). The alternative, to hammer into the side of a police car! I pulled up with about an inch to spare!

The cops had accents so thick you could butter bread with them (huh? - Ed), the only bit I understood was a fist waved under my nose. I was a pitiful sight, shaking with the cold and wet and this must've got to the hard-eyed duo as they let me off with some kind of warning. I think so, anyway, as they didn't issue any paperwork and were almost breaking into hysterical laughter by the time I was allowed to remount the Kawasaki. Of course, the bike took that exact moment to refuse to start, only came to life just as I was really beginning to despair and the battery had almost reached melt-down. More hassle followed as I tried to convince various aged landladies that I was actually a member of the human race!

The relief of dry clothes, a few beers, and a young Scottish babe for the night soon had me raring to go the next day. Even though the sun shone brightly, I togged up in full waterproofs. Typically, the temperatures reached record highs, the only sign of water the sweat pouring off me even though I often tore the Kawasaki through the ton on the Scottish back roads. Though the bike was a heavy old beast, with a bit of muscle I could hurl it around meandering sheep and the odd lurching tractor. Or use the brakes which could have the back wheel a couple of feet off the ground if I applied too much muscle, something worn stockers couldn't hope to emulate. I never tired of riding the bike through the superb scenery, which in fact was a bit too distracting, my attention often wandering from the ribbon of tarmac ahead.

The GPz's major limitation was a lack of ground clearance which clicked in before the relatively modern Metz's began to lose their grip (expect 6000 miles rear, 7500 miles front). In its favour, it didn't try to hinge the back wheel off the road when something dug in, just lurched in a dangerous manner. Hanging off the bike, keeping it as upright as possible, combined with cutting up corners in a highly illegal manner (cagers not amused when forced to play chicken on a nice day trip out in the sun), improved my times and even allowed me to wallow past the odd poseur on a big replica, though I didn't have a hope in hell of keeping the really fast maniacs in sight even if they were armed with a mere 600.

The aircooled DOHC mill made a bit over 80 horses when in fine fettle, which included doing the valves every 5000 miles. They would last for a lot longer without burning out, but set up perfectly the engine had a sharp edge that made a neglected motor seem very tame. It was worth the expense to experience the thrill. Top speed was an indicated 145mph - Kawasaki clocks are notoriously optimistic, so I'd take the 135mph on my friend's K1100 who was also speed testing at the same time as a fairer gauge of the bike's ability. With its half fairing I was as happy as a vicar in a brothel at 120mph. The engine's only note of discord, a ruinous 25mpg! To be fair, in general running it was relatively easy to better 50mpg.

With the motor perfectly tuned, vibration wasn't a problem unless the bike was really pushed when the bars and pegs began to thrum. I'd had the bike long enough, and loved it enough, to take this as a sign to back off pronto. As the engine's state of tune faded a bit the vibes began to become more intrusive, especially in the 5000-8000rpm range. By the time 5000 miles were done it was feeling its age, crying out for attention. The tune-up invariably reinvented the old devil. I've ridden some GPZ's, with similar 50,000 plus miles under their wheels, that have felt a right bag of nails but still managed to knock out similar speed and acceleration to my own bike. Go figure.

If the 750 has a strong top end kick, the acceleration from 6000 revs onwards often lightening the front end and shaking the bars (scared the shit out of me the first time it happened but it never developed into anything bad), it would also run nicely laid back at low revs. Not exactly full of neck breaking torque but with sensible selection of gearing it would bumble through town at next to no revs and still pull evenly - mind, the bike needs new rear sprocket rubbers every year. Slow running, a useful feature when the stock silencers rust out, the only way to hustle past the cops without being mowed down in the urge to administer instant fines.

I tried various 4-1's but could never get the carbs to match. The local Kawasaki dealer had the bike for a week, fared no better. I was so shocked when he said there was no charge that I ordered a new 4-2 system on the spot - 199 notes, off the back of a lorry, nod, wink - according to the dealer. Given that the silencers barely last for three years it's a serious rip-off. Any sensible government would mandate that all exhaust systems are rustproof stainless steel, that would kill off the need to buy dodgy 4-1's. My particular engine would run fine either at high or low revs but not both depending on the carb's jetting. Oddly, the bike ran fine if loudly on a rotted through 4-2 stock system!

Getting back to my recent swing through the Scottish Highlands, more wet spells did further damage to the integrity of the engine, making it run like there was a spark plug burning out. I tried various remedies - WD40, extended mudguard, new HT leads and caps, etc - but none made the slightest bit of difference. The bike didn't like the wet. Out of about nine other GPz750's, I found one owner who admitted to having a similar problem. Worth jet-washing a bike before handing over the cash to see if the deluge of water does the engine in! Could make all the difference.

Time to trade it for something more reliable in the wet, or move to somewhere nicer? Neither are on the cards. Despite the GPz's limitations, and sheer aged design, it's an old friend that has been all over the place with me in the saddle and never really let me down. Hopelessly outclassed by the modern replicas, it nevertheless gets the job done in a rather splendid way and promises more of the same for the next 50,000 miles - though some engines have major top end hassles, the way to keep the mill in line is regular servicing and I know someone who has done 134,000 miles with the mill still basically stock. A little bit of tender loving care goes a long way.

Joe Cummings