Thank F... goodness For Seven-Fifties!
They were all the rage in the '90's. World Superbikes kept them firmly in the minds of any pub road-racer. I was just starting out on the road, but wanted a blue ZXR750 with those Hoover tubes looking so bloody cool coming out of the tank. Ooh yeah. And let's not forget the rare RC30...
Local fast boys had GSXR750's and wheelied from the lights constantly, telling me about the gearbox rebuilds from continual wheelie abuse. It was music to my ears at that age! Yeah, there were 1100's, and the all new Fireblade, but it was the 750's that were racing round the track against 916 Ducatis.
And then...
Everything changed. 600's got quicker, the R1 came along and annihilated the ageing 'blade. A few years later, Suzuki had a thou too and suddenly WSBK was destined for 1000cc fours as well as the V-twins. The midrange 750's started to die out - after all, they weren't wanted in terms of sales. The ZX7R hung in there for a while, but the only true sports bike to maintain that displacement was the GSXR, all those years after it's formidable launch in '85.
And what a good move by Suzuki.
Yeah, thou's are great fun 'cause they're quick. But how much power can you actually make use of on the road? There was a time when a big bike was limited by its poor chassis. You might have horsepower, but you're going to die if you try to exploit it. Not so much nowadays. They let you get away with a lot, but also make you very lazy. Someone faster than you in a corner? Just open up on the straight and reel him back in. You end up riding around on quarter throttle thinking you're Troy Bayliss, while there's a 600 stuck up your chuffer trying to hurry you along in the corners!
Looking at the latest thou's now, I can't help thinking that all the electronic aids designed to make them faster/safer are dulling the basic virtues of riding. Launch control, traction control, wheelie control... strewth, what about my control?
Sure, gadgets are great, but go out there and get on a real bike for a bit. Give the brain something to do, you might actually enjoy it...
You can put the insulation tape away too!
It maybe considered pedantic, considering the rest of the bike at the moment, but I didn't like the white, heat resistant (?) sheathing on the wiring from the signal generator. It was torn in places, fraying and looked scruffy - not really the look I was going for (for the wiring at least).
So, with a little bit of looking around on the dock of the eBay, I found some Techflex. A plastic braided sleeve which expands when you push it together so that you can get it over various looms, hoses or cables etc. When it goes back to its original length, it tightens back up and looks great. Worth a shot of anyone's money I thought.
Here's the old covering looking a bit dilapidated. I'd cleaned it up as best I could, but some things have their limits.
Misfire in the Wet? Weak Spark?
Sat under the tank, they tend to get forgotten. But the leads that take the all important spark to the plugs need to be fully-insulated. If moisture gets in where the coil makes contact with the copper-cored plug lead, your 40,000 volts will probably make its way down the side to earth, rather than putting a spark across your plug electrodes. Why? Because it's lazy and wants the easy path. Wouldn't we all?
If you've ever touched a distributor cap, or lead, on an engine with a misfire, you might have felt the same sort of kick. It's easier to find a path to earth through you, than fire a spark across two metal points that are 0.75mm or more apart, especially in a cylinder containing high pressure air/fuel mixture.
The same can be said for the other end where your plug caps are. The rubber sealing boots are falling apart on the GSX's caps, so I'm putting new NGK's on it. For the price of them, it's not worth taking chances.
So what's that got to do with the price of fish?
Well, the original retaining clips for the plug leads had long since made for the hills. When the bike came to me the HT leads were hanging in by the fact that they were completely rigid and couldn't move, and a bit of good luck thrown in. Don't get me wrong, the bike ran fine, but it would have been different in rain.
Later coils did away with the clips altogether, and came factory sealed with a resin of some sort. As much as I would like them to go back together as Mr Denso wanted, without new clips, I'm going to have to seal them in semi-permanently too.
Considering the state of it, that's pretty impressive.
With water ingress obvious - the carb tops have almost rusted through, the exhaust pipes have rotted out, and the engine is severely corroded, I wasn't expecting too much from the little twin. The inlet rubbers had come away from the alloy plates that mount to the head, which made it a little hard to get it running.
But today I decided to check the compression to get some idea on the internals, it wasn't pretty. 50psi was about as good as it got. That's why, in my opinion, it's better to get an engine running before strip down, but each to their own. Once it's running, it'll clear out a lot of the crap hanging round inside (and there was a lot of rubbish in the ports!). It puts pressure on the prison rings, which start to scrape the bores properly. Fuel/air mixture going through helps to clean valve stems and seats. All of this should help the low compression and, if it runs, gives you some idea on the bottom end. If you pull apart an engine without having heard it, you'll probably end up replacing every component inside for peace of mind.
New parts are rolling in fast.
But some of the old bits seem to have done a bunk! I cleaned, painted (then scratched) a LH handlebar switch last week. Convinced it wasn't the one off this bike, and that it came in a box of Katana bits, I did it anyway. Why didn't I think it was off this GSX? The choke lever is snapped off on the Katana one.
I just went through all the pics I took of the bike and, sure enough, the choke lever is intact on the original switch - but where the f#*k is it?
I had a massive clear-out and general tidy in the garage this weekend and went through all the boxes. The switch and clutch lever have definitely gone AWOL. Oh well, hopefully they'll turn up soon.
In the meantime, new acquisitions have been turning up while I had some spare cash. Needing new master cylinder reservoirs, I went looking on good old eBay. A nice, anodised black, aluminium cylindrical reservoir was found for the princely sum of $7.55 delivered. How could you possibly go wrong?
Cars ain't my bag... but this thing is cool, old, and I love it! Just take a look at the restoration of this huge-engined Fiat S.76 racer.
Massive 7.5" pistons equalling a twenty-eight litre displacement! I'll leave the rest of the story to the experts.
You can read more about it, and see the engine rebuild pics, at The Old Motor or check out the guy who's been following it from the start, Stefan Marjoram.
