Today was the first outing to a track for my car MK Indy ZX9R (C1)

When after a few laps (5-10) I went for 6th ang got nothing but revs. hammered the gear leaver a few time and in the end got 5th.

so pulled in checked it out and all looks fine, so I let the car cool down and went back out and the same thing happened again not every time but every now and then.

on my last few laps I even had this happen on down shifts too.

I had the engine serviced at a kawasaki dealor last saturday fyi.

Any ideas???

Thanks in advance

YQUSTA

Time to look for a new gearbox (engine).

Did it go into gear and then jump out when the power was applied? Would it hold the revs under a trailing throttle?

Yes = worn dogs on 6th gear. The repair is to strip the bottom of the engine casing to remove the gearbox. The gears then slip off the shaft and you can fit new ones. I had it done on my R1 engine. Some of the gears are cheap (£20) some are a bit more expensive. 6th usually mates to 2nd and on the R1 they are some of the cheaper gears. You'll need gaskets too.

No = give us some more details.

If you do decide to look for a new gearbox (or engine) then it'd be worth trying to get an E model as the box is stronger.

How long have you had the car and how often do you drive it?

Going from what you've said, it sounds like you're hitting false neutrals rather than it jumping out of gear. First thing I'd check is the gear linkage. Assuming it's connected by rods, disconnect each link and ensure the individual sections move freely, then re-connect it and make sure all connections are tight.

You do need to be quite firm with motorbike gearboxes, you don't want to change gear slowly and gently. Do it quick and positively.

If the linkages and your technique are ok, then you'll need to start looking at the gearbox.

Phil

I bought the car about 2 month's ago.

I checked the gear linkage at the track and all looked ok, 1 thing I did notice is that it moves further when down shifting than up (don't know if that is normal)

trust me I was firm

It didnt appear to go into gear at all when it revved out until a bit of up and down shifting it would finally find 1.

to add a little more detail

I have done about 1000 miles in the car on the road and never have a problem, even on the 2 hour drive home no missed gears at all.

the track was Llandow and as said before it only happened when the car had been pushed hard for a few laps but once cooled down the problem disapeared until I went back out on track and pushed hard again.

It wasn't all the time but say twice in 10-15 laps

when I was missing 6th it was on the back straight only, but again not every lap and on the missed down shift it was at the end of the pit straight, again not every lap.

Thanks

Yqusta

Bump

If it only happens whilst on track and only once or twice in every 10-15 laps, I personally wouldn't worry too much about it. If you were racing competitively, then it may be a cause for concern but on a trackday it's just a pain in the backside every now and again.

If it doesn't cure itself, wait until it either gets worse or something breaks. Then fix it.

You might even find that a change of oil will cure it.

Phil

[Edited on 16-9-08 by Hellfire]

thanks to all who responded

Hellfire I had the oil changed a week ago so it may be that this is the cause? but as I had it done along with a full engine service at a kawasaki dealer im hoping it just a coincidence and not that they put the wrong oil in.

I will monitor the problem and as you say I dont do many trak days and i can hndel it only happening a few times in the day.

YQUSTA

C1 boxes were notoriously unreliable with false neutrals and poor durability. If I remember rightly they were subject to a recall and if yours didn't get done it may still have it's original problem gearbox.

IIRC, the problem with the C1 gearbox is that it is prone to jumping out of third gear due to insufficient contact between the dogs when engaged with 5th, which ultimately leads to premature wear and eventually failure.

Phil

The problem with mine dosent seam to be 3rd just 6th on up shifts and allsorts on down shifts.

looked down the tunnel and saw the connection from the rod to the gear leaver was loose so next job is to see if this is correct or if it needs tightening?

thanks for the help and surgestions

YQUSTA

If it occurs when particularly hot - it may be due to a slight increase in expansion of the linkages or backlash even. I'd try a little adjustment before you go condemning it...

Steve

good thinking hellfire on the expansion and could you explain to an idot what is ment by "backlash" as you can probably tell I have very little experience with bike engines well to be honest very little with any engines.

hope to get to look at it on saturday.

YQUSTA