Last week end I had my first track day. Amazing!

Most of the bikes were 600 & 1000s, with quite a higher top speed than my 21, but I'll tell you about that in other post.

The fact is that my new front bridgestone 090 is now dead, while the rear one is more than OK. Sjould I install the same 090 if I keep the rear one?

I've allways been told that this should not be done, but there's a lot of experience out there and maybe someone has already tryed this.

I've seen some very fast guys mix tyres, as long as they're both good tyres I wouldn't worry.
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quote:

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Originally posted by mj43:
All in all I was chuffed. The engine was my latest flowed cases with standard KR-1 barrels, pistons and cylinder head (my race barrels are still at the platers). Bike wasn't as fast as mine but it could live with the two VJ23's and the NSR's one of which is F3 spec.

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The tyre boffins will tell you not to mix tyres as you may get vibrations or other weird things coming through that affect the handling of the bike.


I don't think I ride hard or fast enough to get that, and if I did, I'm not at the level (yet I hope!) to be able to confidently say it was the mixed tyre levels (if I mixed my tyres).

I've searched the forum for tyre recommendations:

- Almost no feedback on Michelins.
- Dunlops are considered sticky but wear faster.
- Bridgestones are considered all rounders and best in the wet (although some people don't like them at all).

So maybe I should get another 090...

But, why did it wear so fast? I am starting to think it is becouse of me. Not only the tyre is gone, but half of the footpegs, brake pedal and gear shift lever. The bad thing about this is that I was the slowest one on the track!

I am goint to try to talk to the bridgstone rep and see if I can get a discount on a new tyre. Will keep you updated.

Get your tyre pressures right to prevent premature wear. Pressure should rise 10-12% when hot from their cold setting. If it rises more than this, raise the cold pressure as the tyre is moving about too much and generating too much heat.

If you're grinding things off the bike you are not hanging off enough!

Fit rearset pegs or make a bracket to raise the standard ones (I used a bit of steel about 3 inches long between the bottom mount and frame, causing the peg to rotate up and back around the top bolt).
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MC21SP Plaything
BMW F800GS World crushing transport
FJ1100 Sporting relic

I mix tyres without problems...

I like a front tyre that feels good under hard braking and a rear tyre that feels good hooking up on the gas.

To me these are very separate, especially at the track where I'm either on the gas or braking, all the time.

I also use a slightly firmer rear than front because in my view if I'm gonna really push I want any 'negative' feedback from the tyres/grip to come from the rear well before it comes from the front.

My 2 cents worth.
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Stop sniffing my ring

MC28SP
KLX110 hotrod
CAG Minimoto
1997 WRX
21 Speed Bike
162 Smurfs

Oh yeah,

If you are grinding then you may need one of the following:

A new rear shock

A serious diet, fatty

A set of rearsets

Good luck
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Stop sniffing my ring

MC28SP
KLX110 hotrod
CAG Minimoto
1997 WRX
21 Speed Bike
162 Smurfs

Well, thanks to all responders.

I am only 65 kg, so that is not an issue. I guess I could use the std japanese setings.
Rear shock. Measured sag: 20 mm without rider, 25 with rider. That seems also OK
Hanging off. Hardly anything, so that needs to be improved.
Tyre pressures. I used the same pressures as on the street, did not change them, did not check them just after riding. Again, this needs...
Feelings. I can not feel anything, good or bad on the rear. Probably as the poor things only outputs just above 50. The front was really bad when on the brakes. I could not get it precisely on sharp turns. Two more rings on preload and 2 clicks on compression improved significantly. However I can not say if this is the best it can get or not. Still, when in the sharp turn, the bike does not like the brake to be touched (just for correction purposes, though).

The track is a new one in northen spain, just 1 month old, impressive but not very nice for bikes. If you have a look at the track (www.circuitodenavarra.com) you'll understand.

You HAVE to sort you suspension out, and even with only 50hp you will run rings round bigger bikes.

I once watched an open 400 race which was won by a 125. Bloody impressive considering some of the 400's were making over 80hp.

And as for not checking tyre pressure... you are a daft bugger and lucky not to have crashed!
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MC21SP Plaything
BMW F800GS World crushing transport
FJ1100 Sporting relic

I WANT to sort my suspension out, but how? I've read the tuning section, understand how to set the sag/preload. Other than that, if the bike is stable, should I touch things?

I just sold my YPVS and now I feel in heaven, this bike is perfect for me (for the time being).

I guess that, if you have time to spare at the track, you can experiment with different settings and control a) how it feels and b) how fast you lap. But you need the time...

Or you can drop the bike at some suspension expert. But they only work in "static" mode. They can rebuild suspensions OK, but it is your task to set them up correctly. At least that's what I've seen locally. Right? Am I missing something?

I don' understand the expression "will run rings round bigger bikes. ". However, the track was full with ducatis, R1/R6s, a few fireblades, BMW RR,...most of them track prepared. They all passed me after the turns but I seemed to get by them at the next turn. So the bike brakes OK.

I need more track time. And more power.

That's exactly what 'run rings round' means - you will ride round the bigger bikes in the corners.

Remember when setting up suspension it is with you on board, and you're looking for about a third of the travel taken up when you sit on it, measurements in mm aren't really the optimum as they don't account for suspension aging.

Do you have any of the forks showing above the yoke?
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MC21SP Plaything
BMW F800GS World crushing transport
FJ1100 Sporting relic

Nope, forks are not above the yoke. Are you suggesting that dropping the yokes will improve handling at low speed corners? I may try that, but as of now, the bike is stable at high speed, and I'm happy with that.

Fork oil seels seem to be in good shape, no pil coming out of them. Also, no piiting on the bars. However, I will recheck oil level and visit a suspension shop since front damping could possibly be improved...

yes droping the front forks will take a bit of rake out of the front end making it a bit sharper in corners but a bit less stable at high speeds . Hrc suspension set up has the forks droped 14mm

Again, I'd only look at the HRC settings as suggestions, not gospel. You should have the bike set up to suit you, not someone else.

Pushing the forks trough the yokes will speed up the steering at the expense of a little high speed stability (not much) but it will also reduce your ground clearance.

If you're not running wide in corners then stick with the setup you have. If you start finding it very hard to turn or hold a tight line, then make adjustments a little at a time - 10mm or so. Then ride it and see how you get on.

Only change one thing at a time, and take notes of what you changed so you can undo it if need be.
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MC21SP Plaything
BMW F800GS World crushing transport
FJ1100 Sporting relic

You are right, HRC recommends front preload and compression in the middle values. For me, its 70% of maximum.

On slow turns, hard on the brakes and if I manage to do it just in time, lean the bike and there it goes. If I slightly touch the brake once inside, the steering wants to turn.

Other than that, I am happy with the feeling I get at higher speeds. The bike goes where I want.

Changing subject, I've been recommended Michelin pilot road 2ct. Any experience?