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A Story of Reversible Woe
from Graham File

A customer in Oldham, Lancs, whose KR-1S I had tuned, phoned to say he'd acquired an RGV250N and was having trouble getting off the startline. The bike had no mid-range, and as I asked the usual questions to get a picture of what could be wrong, I became more and more amazed.

He had purchased the bike in standard trim and done the usual race mods himself. Next he approached a mjor supplier of RGV race kit parts and the the kit pipes, computer box, and kit carb parts, essential for the first stage of preparing the bike for the race-kit setup. He had trouble sorting out the jetting, back to the supplier... oh, you need the kit cylinders. Still no joy, back again... ih, you need kit heads. Back again, to find he needed kit power-valves, kit gaskets, kit wiring loom, kit throttle, kit pistons, kit reeds.... and so on.

Still no joy. He'd tried 100% avgas, 50/50 avgas, superunleaded, 4 start, but always a flat-spot in the power and lots of detonation, causing seizure after seizure. What was the carb spec? He'd tried so many he'd lost track of what was in there now. How much did the parts cost? 5000! Silence!

More than anything, I felt it was a shame to have had so much agro instead of 5000 of FUN. Value for money and FUN to GRIEF ratio are important in any sport. It seemed that after he had started handing over bundles of cash he felt too embarassed to ask me for advice, and felt awkward even now. He should have known me better than that!

To cut the story down, he sent me the engine, I tried to give him what he wanted. The engine was returned, and the next phone call was much more upbeat. The bike pulls off the line much better, pulls well out of corners, sounds great, no detonation and 2 wins first time out. But a lad was begging him to sell the bike, and the chance of getting some of his money back proved overwhelming and the bike was sold. The buyer was selling his RGV because... have you guessed? ...It would not come off the line, wouldn't drive out of corners, kept detonating, etc.

Time goes on, and a few weeks ago the new owner phoned. Could he have an up-spec, and overhaul. When I asked how he liked the RGV, yes it's a flyer off the start, strong out of corners, but not got the top-end of his old bike, which had been better at passing on the straight. I thought, well, it would, seeing as he had lots to get past after a bad start. I asked about gearing... he'd knocked 2 teeth off the back sprocket because it revved out too early since my tune. I said that was a good sign, thinking to myself, doesn't he realise that it must be about 5mph quicker? NO, he'd still prefer the top-end of the old bike, it would be good to have that on the new bike. How were his results on the old bike? He'd struggled, because of bad starts. And my spec.? Oh, good, 2 wins first time out!

What can be learnt from all this?

  1. A big dyno number is no guarantee of useable power when the machine is ridden, you have to win on the track not the dyno!
  2. Throwing expensive parts at the machine does not guarantee a winning end result.
  3. However far down the road of buying bits and tuning you go, if it's not going the way you want, phone! A 2 call may stop you wasting money that could be put to better use.
  4. Never underestimate the 'X' factor: You, the rider. Races can be won on a machine with less than 1,000,000 bhp if it is easier to rider and gentler on the Psyche.

Graham File - Hythe Motorcycles - 01303 262222

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