Friday, 3 February 2017

Hundred Quid Hacks: Suzuki GT250


The GT250 was the ultimate development of Suzuki's need to turn out two strokes that acted as if they were four strokes.

The 180° crank twin could trace its history back to the late sixties in T200/250 form. The GT750 had its power reduced to a mere 27hp by emission regulations. It needed all its revs to make the bike fly, but even thrashed it could only manage 85mph, little better than more durable and economical rival four stroke twins.

Furthermore, the engine had a nasty habit of chewing up the needle roller small end bearings, which end up circulating around the engine, taking out the crankshaft on the way. The crankshaft is a built up job that has to be traded in for a new one, expect between twenty and thirty grand before it needs replacing.

Something called Ram Air Cooling adorned the cylinder head. This was a finned aluminium plate that was supposed to direct air onto the head, but why it was needed when the more powerful T250 survived without it, escapes rational explanation.

The engine does benefit from Suzuki's direct oil injection, but it's not as accurate as the GT500's and the 250 is usually followed by a cloud of blue smoke. As with the 500, the oil pump gears can strip, engine bolts can snap and cyllnder head bolts can strip their threads. But these are fairly rare events.

Handling was typical of mid-seventies Jap technology with poorly damped suspension and far from rigid frame. The real fun starts when the swinging arm bearings wear and the bikes goes into some vicious speed wobbles above 75mph.

The front disc is just as cheap and nasty as the rolling chassis. Lacking. power, precision and feedback it's bad enough in the dry; wet weather leaves the bike at the mercy of whatever gods happen to be in the vicinity.

Lurid rear wheel slides due to the weak swinging arm and lack of feedback are combined with heart stopping sudden applications of the front disc when the water finally clears off the disc. The bike is only saved by the lack of a violent powerband and a slick gearbox that holds no nasty surprises.

Fuel varies between 35mpg (run along on a wide open throttle) and 60mpg (riding with the throttle just off the stop), averaging out at 45mpg. Rear tyres last for about ten grand, front for twelve and a half.

Chains go for about ten grand, although most owners seem to keep on riding with worn out jobs, so it'll probably need a new set of; sprockets. Front disc pad lasts for eight grand - cheaper pattern pads work no better or worst than stock items. The SLS drum's shoes go for around fourteen thousand miles.

To find one of these bikes in really good condition is going to be very difficult. Most of them were owned as first bikes by learners and got rather thrashed and neglected. The engine's quite easy to strip down and there are loads of cheap parts available from breakers. There are also many tuning goodies, but these make the engine even less reliable, and the extra speed takes the handling down to Kawasaki triple level.

The final '78 model had better suspension, a better paint job (but still looked very bland because of the slab sided tank) and an even less powerful motor that couldn't get the bike past 80mph. The new X7 that replaced the GT reintroduced the fast kicks of the T250 but was even more fragile.

With a dubious engine and poor chassis the GT250 has very little to offer on the used market where there are just so many old 250s vying for the attention of poverty stricken punters. The only thing the bike has going for it is cheapness. It's possible to pick up a non-runner for as little as £25 and something that has an engine which makes the appropriate noises for just fifty quid.

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