Tipping it in

So, had a chance to play around a bit more on the 9R this afternoon, during
otherwise routine commuting. I remembered Champ's words a while back about
steering being slower on the bigger bike, so I /really tried/ to get it over.
After trying quite a bit, I have realised what happens, and why I'm not
confident.

Coming up to the bend, I get my body round the bike a little in preparation.
When the bend starts, I tip it in, but it only leans up to a point. I push
harder, nothing happens for a while, then /suddenly/, it leans further and
everything feels rather light. At this point, I back off, probably without
reason, but it's just disconcerting, unlike the NC30, where leaning is
somewhat smoother, and not punctuated by a sort of plateau. Maybe I need to
ride some other litre bikes to see how they handle in comparison.

Bit of a ramble, but I can't describe it much better than that.
If anyone with a clue can share, I'd be grateful.

 

Nothing to do with the size of the bike. Your rear tyre is squared
off.

 

Exactly what it sounds like to me.

Chuck it in a bit harder and it'll be fine.

 

and me.

exactly - forget this "progressive lean" bollocks - give it the old
body english give the bars a firm tug, and countersteer like a twat.

What's the worst that can happen?

 

As others have said - it's your tyres. ZX9Rs steer quite nicely and
progressively on new rubber; once the rear is squared off, they do
what you describe. Less likely, but also possible, is that the front
has gone 'triangular', but you have to brake into corners to achieve
that.

 

*waves*

 

Sorry to be boring, but they're all right.
FireBlades with squared tyres do exactly the same thing.

 

heh. And no, not the way you do it.

I'm talking about still braking *as* you initiate the turn.

 

I can do that.

And all the way through it.

And out the other side.

 

And all the way to the apex. That takes some getting your head round,
but makes me faster

 

It depends on the corner. All corners have a entry phase, a steady
speed phase, and an exit phase. Some have quite long 'steady speed'
phases, and can have several apexes (eg Gerrards at Mallory). You
can't 'brake all the way to the apex' there - it's more important to
get the bike well set at corner entry to maximise your corner speed
thru the long middle section before you can get on the gas.

Other corners have almost no steady speed phase at all - as soon as
you've finished slowing, you're on the gas on the way out. Many
hairpins are like this. These are the ones you can 'brake to the
apex' on, as you spend much less time lent over, and you lean over
less anyway, as corner speed is not what makes you fast thru these -
it's getting in fast, and getting out fast.

Horses for courses.

 

It most certainly is. It's something Danny and Ratty taught me to do.
It took an obscene number of laps of different circuits to get there,
but the result is quite startling once you learn that the front isn't
going to break away as long as you're progressive with the brake.

You brake late and hard, and then ease it off as you tip in, and hold
it on the front brake still scrubbing off speed as you go in all the
way to the apex, all the time coming off the brake gently and
progressively the deeper you go. By the time you're ready to hold a
steady throttle through the apex you're completely off the brake and
the suspension has settled itself, then it's wind the power on again as
you exit and get the bike upright. The object of it is to leave the
braking later and later using your time banked over as braking time and
not just steady throttle time. With me it's made the difference between
previously riding in the top 10% of inters and now being able to ride
in the middle of fast group. It fucks the front tyre though, but wgaf
about that.

I still haven't mastered the art of getting back on the power earlier
and harder on the exit. At the moment I'm still a bit hamfisted and
that's resulted in a couple of slides that shook my confidence a
little. Not fun when it's your mate's ZX10R that he's trying to sell.

I save these sort of antics for the track, my confidence out there is
200 times what I have on the road. Road riding is done at a sedate pace
nowadays.

 

What he said. You can't use it at every corner. Champ's example of
Gerards is spot on, but the left into Edwinas is a prime example of
where you can, but not the right out of it. Mallory's hairpin is a
fucker because the braking zone on the right line in is as bumpy as
****, so I tend to be a bit cautious there, or I brake harder on the
smooth bit in centre of track and then move across to the right line if
I can. If I don't think I'll make it into gap I back off on the
approach and play follow my leader round til we exit the Bus-stop.

 

I suspected as much, a while ago[1]. I have experienced similar effects with
my 600s in the past, with tyres that came on the bike, and the handling has
been much improved when I've replaced the tyres due to wear.

The tyres look to have significant tread left, I've got no dosh at the moment,
and I can't justify replacing them just because of this. Is it actually
dangerous or does it just /feel/ weird?

I'm a bit chuffed that I actually managed to describe the symptoms well enough
that they could be recognised, I must be getting better at feeling what's
going on.

[1] http://groups.google.co.uk/group/uk.rec.motorcycles/msg/3b4c709aff72149d

 

Fine as in it won't feel weird, or fine as in it will still feel weird but I'm
no more likely to bin it than with a good tyre?

 

I don't do that, I thought you should have finished braking by then. I reckon
it's the rear, fucking common that it is.

<ponders going out to garage to measure tread>

 

Once you've gone over the "squared off" ridge on the tyre, onto the
relatively virgin rubber on the outer third, you will have excellent grip.
Especially if the tyre is a dual compound thing, with softer, stickier
rubber on the outer sections.

 

Fucking great. I reckon that if I can learn to push it more, it will be a
good lesson for me, the way that Keith Code talks about overcoming
counter-productive survival reactions.

I can see why there is resistance to further leaning, but I'm quite curious as
to the physics of why it feels so light under me for the split-second after I
push it harder.

I wonder if it's possible to un-square it on an appropriate bit of road. <g>

 

stares pointedly

 

Further to what other people have already added, I'd add that it'll
still feel a bit weird, but you'll get through the weirdness much
quicker, possibly not even noticing it.

Mind, doing this on warm, dry roads is relatively easy; having the
confidence to do it on a warm, wet road requires greater levels of
cojones. Cold, wet, greasy roads just put me into tiptoe mode when the
tyre's like that.