Whilst on a trackday (car been driven hard by someone else) a knocking noise was heard from the gearbox and when in high gears it would jump out of gear sometimes. So, the car was pulled over into the pits and switched off. The driver described the fault so we started to investigate.

The box was put into what is normaly first gear but the car could be pushed forwards and backwards as if in nuetral. When the box was put into second it felt as if it was dropping into neutral but when the cars was pushed forward in this position something locked up in the gearbox, stopping the car as if it was in gear but the clutch made no difference and the box stays locked up. No other gears after this position can be selected, only back down the range to what is presumed to be the first gear position.
Several hours after this happend, when the engine was cool the fault was still present.

The sump has been removed and the engine turned upside down on the stand. There are no lumps of metal in the sump, but a few shavings. The selection of all gears seems possible now the engine is upside down although it did 'stick' around 2nd the odd time.
I can't see anything obviously damaged. Any ideas as an upside down engine is not very practical?!

Apparently they fail a lot and are expensive to fix. The local bike shop warned me when I was talking to them about buying an engine. They said it's about £1500 just for the parts. Contact Colin (colibriman) as a new engine would be cheaper. Keep your old one for spares.

ZX9 boxes are complete b*llocks, my first one lasted 1 track day before it started to cause problems. I got lucky - my local college had a C engine and let me have the input/output shalfs for £50.

You just have to be very careful when changing down at high revs, you either have to blip the throttle, or let the revs drop. It''s probably the most significant reason I'm not as impressed with the driving experience of my car as I'm always worried when driving it hard - especially on track - of knackering the gears again, as I know I won't get so luck again.

When I investigated the cogs, the only sign of a problem was a slight rounding of the corners where two meshed.

Not had another chance to look at the engine but if it's so expensive to sort and likely to happen again, then now might be a good opportunity to change the engine and upgrade to something a bit more powerful and more reliable.

Are the R1 engines more tolerant to 'abusive' driving? Anyone had problems?

Regarding the R1 - you would really have to go some to break one. I navigate for a mate of mine in a RWD R1 Mini on stage rallies and I guarantee you will not abuse an engine to anything like the same extent no matter how many track days etc you do.

The Mini is fitted with a stock 98 R1 motor with only an uprated Barnett clutch and a little overfilled with fully synthetic Rock oil. We have rallied for the past 2 years in it and after a recent checkup there was absolutely no sign of any wear on the gearbox. He only uses the clutch off the line and when coming down into 1st or 2nd gear. Apart from that it is just banged into gear either up or down the box.

At an event at Cadwell Park last year the master cylinder went on the 2nd stage and we didn't have a spare. We completed the rest of the rally just using the engine for braking. Despite banging it down the box with some astronomical revs on it didn't miss a beat. Needless to say there was only ever going to be one choice of engine for me.

I see you are pretty local - if you fancy seeing some live R1 punishment why not come down to RAF Swinderby on the A46 between Lincoln and Newark on Sunday where we will be kicking some butt on the Wolds rally. Failing that I have got an in-car and out of car video of the Cadwell event and would be happy to drop it in to you next time I am in York