performance figures

So what happens when you opt for a different model or brand of tyre,
-- same model- same brand-narrower tyre -profile flattens

This will give an idea of what camber alone can do to lean angles.

give me a chance and I will explain any part you are not trying to
understand. Pull it to bits with facts--fine!

I presume you agree-- great!
be gentle with me. Read the first posting
regards Dave R

 

Nope. I'm talking both fitted and up on a bikeshop shelf. That's just
how they make them, for some bizzare reason.

A D207F in a 170 section looks just as square when fitted to the 5.5"
rear rim of a ZX-6R (it was the standard size on the model preceding
mine-exact same wheel, mind you), and the narrower 1993 GSX-R750 item I
had on my FZR600 bitsa, for example.

 

i got 170 section on my bmw
have seen the 180 sections on other bikes
Mine seems rounder and higher. when seen side by side
this on a 5 inch rim.
I also find I don't have to lean as far to take the same corner as
others on bikes with wider tyres.
(this is keeping the same speed as the rider in front but then other
factors such as bike geometry come into play

 

It does but tyre widths aren't just about corners, they're also about
acceleration - skinnier rears turn in quicker, but have a different
shaped contact patch for putting the power down - it's a trade off.

Some bikes benefit from ditching the 190 for a 180, depends on the bike,
the rider, the suspension config, the track etc etc

JL

 

Sorry buddy, but it has a kernel of truth to it, the handling of a
number of bikes running 190 and 200 rears (not to mention that Yankee
custom cruiser with the 250) benefit handling wise from going down to
180s, particularly when ridden by people who aren't Mick Doohan who are
more likely to get benefit from quicker turn in then the extra traction
when fully cranked over...

You're going to have to include me in that, and I've tested the theory.
I've ridden a TRX with a 180 rear, it sucked. Looked nice, but sucked.

JL

 

Not to mention the all time classic ! The Hornet 250 with the 180 rear
tyre on a 40Hp bike

JL
(go on, spin that up on corner exit ya bastard !)

 

Well shit I've never seen anyone shoot down their own argument in such a
short time !

JL

 

Umm Yeah right ! That's why all those 2 year old GSXR1000's with 6000km
on the clock keep coming up for sale, after being traded in on the new
R1 because it looked sexier (substitute GSXR, R1, CBR1000 and ZX10R as
you feel appropriate).

Most sportsbikes get sold as fashion accessories, they are the segment
of the market MORE fashion conscious than the cruisers.

JL

You seem to have subsituted real for perceived.

It's the ability to boast about how fast it is that sells *most* sports
bikes, not whether Joe Owner can actually beat the postie around the
block or not.

JL

 

I know that taking my VTR from a 180/55 rear down to a 170/60 made it turn
much better.

Al

 

ahh now if you'd said that I wouldn't have argued, or at least not as
much I agree, it's not all about aesthetics - there's definitely
value in the wider tyres, but there's also not a linear - wider = better
equation, there's more parameters than that

An interesting theory, I can't say I buy it, but it's plausible. I'd be
betting on overtyring for aesthetics and as a marketing "signal" that
it's fast and sporty.

Again, plausible but i don't really buy it, people punt cb250s into
ditches as they're hardly over powered.

No shit ! That was my point

Ahh but that wasn't the statement was it ? "aesthetics plays a big part
in tyre width to the expense of handling." A big part does not equal
the only part, and there's definitely some truth to it, the Daytona for
example runs a 190 for aesthetic reasons - it's handling is immensely
improved by a 180. As for unwillingness to consider the question, well,
I've found most people are unwilling to countenance downsizing a width
could improve their handling - most people think bigger is better and
that's why the marketing dept. specifies the widest practical tyre.


JL

 

A kernel is, typically, not large enough to constitute a "big part" of
anything.

What unfurls my sulphur crest is the catch-all, "Ah, it's all looks,
mate. Back in my day..." and so forth.

I'd much sooner believe that aesthetics are the minor reason most bikes
are overtyred by a size from stock. The major reason, by some margin,
would be deliberate sabotage of the bike's handling to make it more
amenable to circumspect riding. The steering is a bit more lethargic
than it would otherwise be, encouraging people to tip in more gradually
and, consequently, carry less speed into turns.

The extra width at the rear would also make it a bit more difficult to
spin the tyre up under power, however hard that might be, anyway.

Result of both is fewer people ending up in ditches from pushing the
bikes because they felt good when pushed. However many times you read
the term "confidence-inspiring" in bikemag articles, past a certain
point, stock bikes come with their chassis tuned to be anything but.

Stock, TRX's didn't come with 180-section rears.

I ran 180 rears on my R1, too. Didn't improve the handling nothing like
the extra rear ride height that resulted from replacing the stock shock
with a Pen$ke. With the extra rear ride height, the bike held a line
under power past the apex like nothing else on earth, encouraging heaps
of gas on the exit, but understeering right off the road if at least a
bit of gas wasn't used to get the weight off the front. However good the
bike felt set up like that, it had lots of potential to spear a
reluctant rider into the armco or highside an overconfident rider over
it. Instead, Yamaha released it with the chassis set up so that gassing
it up too hard on the exit would cause the bike to understeer. Once that
happens a few times to someone getting used to the bike, they learn
their lesson and stop pushing.

Bottom line, saying that fatter-than-necessary tyres on sportsbikes are
just fashion is a fig leaf; it shows an unwillingness to consider the
question more deeply, but an unpreparedness to admit being uninformed.

 

Same for my R1100S dropping from a 170 to a 160.

Boxer

 

To be fair, a lot of those GSX-R1000's get put up for sale because the
owner's decided to switch their flash-money expenditure to a powerboat,
or a jetski, or a V8 ute, and not to another bike.

The more time goes by, the more I come to see this as a sneer
perpetuated by the Gerries of this world. A worryingly large number of

"Fashion" implies no function beyond the aesthetic, and, to be honest,
it's not really a word that can be applied when discussing any type of
dynamic product.

This year's new thing must either be perceptibly "faster" than last
year's thing (eg. the original GSX-R1000 vs the undeniably prettier
carbed R1), or negligibly "faster" and significantly prettier (eg. '02
R1 vs original GSX-R1000) in order to sell.

That would be what Paul covered in the bracket in his statement.

Further, arguing that differences in capability aren't tangible is the
talk normally heard from bikeshop salesfloor dimwits who have one answer
to "So, how's the new <insert fresh-release bleeding-edge sportsbike
designation> go?", and it's, "Oh, you have to be really pushing it to tell."

Bullshit. If one bike's more capable than another, it's going to feel it
at anything exceeding walking pace, and however much one's core aim in
owning a bike might be to impress da honeyz, they're, ultimately, going
to have to put up with the thing thrumming away between their legs, and
if the thrum isn't favourable, they're going to go for something else.

 

If only I could meet one of them.......
Clem

 

I'll answer the above 3 here: If they were primarily interested in the
dynamics of the machine they'd rack up some Ks on them (and there's
plenty of sports bikes sold with very small Ks on them, I doubt they
were all raced...). While categorising me with Gerry is undoubtably an
insult, I don't think it's a particularly founded one. Your example
above puts the lie to your argument, if someone is selling their "flash
money" toy to buy another flash money toy, I find it hard to believe
that there's been any more than a brief aesthetic flirtation with it -
the sort of rider who can manage to extract even a smidgin of the
capability from a current litre bike isn't about to stop riding, surely
? I find it far easier to believe that the sort of person who swaps one
interchangeable flash toy for another interchangeable flash toy
(quantity of wheels variable) is the sort of guy you come up behind on
the old rd. wobbling through the corners at the advisory sign speed.

It'll remain opinion between us until someone does some research on it...

Pretty sells over performance, otherwise the 916-996 Ducati would never
have sold, meagre hp compared to an R1, slower lap times, twice as
expensive for less performance...aesthetics shifts the majority of
bikes. Would an R1 or CBR thou sell if it was pig ugly (ummm scrub that
argument, hayabusa's sell

Joking aside, there's a segment for whom performance is paramount,
there's a segment for whom aesthetics are paramount, and a bulk for whom
it's a combination of both...

I'd buy the current R1 over the ZX10 despite the Kwaka having more
ponies, because the Yam is prettier, and I'm honest enough to admit that
I'm not going to be able to go any faster on the Kwaka than the Yam. I'm
just not good enough for the extra 5 hp to make any real difference.

Not it's not, he said real regardless of ability to use, I said
perceived. The appearance of "fast/sporty/macho" is more important than
whether it actually gives a performance advantage. It's more important
for a manufacturer to win the numbers war than it is for the bike to
actually be the fastest around a race track in stock form. Numbers is
bench racing ie perceived, laptimes is REAL performance, but you rarely
if ever see those numbers compared.

Your average poseur wants to be on the bike with the biggest HP, highest
top speed, lowest weight, 'cos in a dick measuring argument he wins.
Take it to the local race track and high HP bench racing winning bikes
get embarrassed by other stuff. At superbike school the head instructor
was rounding up R1s on a Trumpy Tiger, hardly a hi po sports weapon...

Real Performance and bench racing (perceived performance) just ain't the
same.

Sorry, in case I've confused the issue, I'm not saying Tigers are better
performers than R1s, just that performance has more facets than the
numbers, yet it's the numbers that sell sports bikes. Hence it's not
about REAL performance, it's about perceived performance. It could
wallow through the corners like a pig in a mud puddle, but if the
numbers say it's the best, it'll sell like hotcakes.

Oh dear I guess i'd better get a job as a salesfloor dimwit then. Ya
know, I can't really tell the difference on a test ride between a ZX10
and an R1, I'm probably as quick as the next guy without being a star -
an average rider for my experience, and quite frankly with 2 decades
experience i don't reckon I could get either of those two anywhere near
their capabilities, and while I could talk about handling differences I
observed or engine performance traits I observed, i doubt there'd be
much difference in my laptimes on either (although reputation has the
CBR being the bike for the mug punter, haven't ridden it yet)

Your seat of the pants can tell the difference between 155 and 160 hp or
whatever the ZX10 and R1 currently have ? (sorry I've forgotten the
numbers 'cos they don't mean much to me) Colour me impressed, the human
dyno huh ?

Which has nothing to do with the performance and everything to do with
the aural aesthetics (and again another reason they manage to sell those
ducatis)

JL

 

I'll answer the above 3 here: If they were primarily interested in the
dynamics of the machine they'd rack up some Ks on them (and there's
plenty of sports bikes sold with very small Ks on them, I doubt they
were all raced...). While categorising me with Gerry is undoubtably an
insult, I don't think it's a particularly founded one. Your example
above puts the lie to your argument, if someone is selling their "flash
money" toy to buy another flash money toy, I find it hard to believe
that there's been any more than a brief aesthetic flirtation with it -
the sort of rider who can manage to extract even a smidgin of the
capability from a current litre bike isn't about to stop riding, surely
? I find it far easier to believe that the sort of person who swaps one
interchangeable flash toy for another interchangeable flash toy
(quantity of wheels variable) is the sort of guy you come up behind on
the old rd. wobbling through the corners at the advisory sign speed.

It'll remain opinion between us until someone does some research on it...

Pretty sells over performance, otherwise the 916-996 Ducati would never
have sold, meagre hp compared to an R1, slower lap times, twice as
expensive for less performance...aesthetics shifts the majority of
bikes. Would an R1 or CBR thou sell if it was pig ugly (ummm scrub that
argument, hayabusa's sell

Joking aside, there's a segment for whom performance is paramount,
there's a segment for whom aesthetics are paramount, and a bulk for whom
it's a combination of both...

I'd buy the current R1 over the ZX10 despite the Kwaka having more
ponies, because the Yam is prettier, and I'm honest enough to admit that
I'm not going to be able to go any faster on the Kwaka than the Yam. I'm
just not good enough for the extra 5 hp to make any real difference.

Not it's not, he said real regardless of ability to use, I said
perceived. The appearance of "fast/sporty/macho" is more important than
whether it actually gives a performance advantage. It's more important
for a manufacturer to win the numbers war than it is for the bike to
actually be the fastest around a race track in stock form. Numbers is
bench racing ie perceived, laptimes is REAL performance, but you rarely
if ever see those numbers compared.

Your average poseur wants to be on the bike with the biggest HP, highest
top speed, lowest weight, 'cos in a dick measuring argument he wins.
Take it to the local race track and high HP bench racing winning bikes
get embarrassed by other stuff. At superbike school the head instructor
was rounding up R1s on a Trumpy Tiger, hardly a hi po sports weapon...

Real Performance and bench racing (perceived performance) just ain't the
same.

Sorry, in case I've confused the issue, I'm not saying Tigers are better
performers than R1s, just that performance has more facets than the
numbers, yet it's the numbers that sell sports bikes. Hence it's not
about REAL performance, it's about perceived performance. It could
wallow through the corners like a pig in a mud puddle, but if the
numbers say it's the best, it'll sell like hotcakes.

Oh dear I guess i'd better get a job as a salesfloor dimwit then. Ya
know, I can't really tell the difference on a test ride between a ZX10
and an R1, I'm probably as quick as the next guy without being a star -
an average rider for my experience, and quite frankly with 2 decades
experience i don't reckon I could get either of those two anywhere near
their capabilities, and while I could talk about handling differences I
observed or engine performance traits I observed, i doubt there'd be
much difference in my laptimes on either (although reputation has the
CBR being the bike for the mug punter, haven't ridden it yet)

Your seat of the pants can tell the difference between 155 and 160 hp or
whatever the ZX10 and R1 currently have ? (sorry I've forgotten the
numbers 'cos they don't mean much to me) Colour me impressed, the human
dyno huh ?

Which has nothing to do with the performance and everything to do with
the aural aesthetics (and again another reason they manage to sell those
ducatis)

JL

 

of....? ****; now I may never know what it is of which I'm one of a large
number....
Fat bastards? (Naah that's a bit too obvious)
BMW riders? (Can't be; I've only had the R1100 for 6 months but I've had
the belief for decades!)
People with large purposful shafts! (In my dreams!)
People who have an "e" in their names? (and no "a"?)
Grumpy old cunts who sometimes point out "wank"; when they're bombarded
with it?
Hmm.... Gerry; you there?
Clem

 

First to fit a 140-section GPR-70 to the back of their Hayabusa wins.

 

Well it'd turn in quickly....

JL
(there's more than one parameter to performance...)

 

IK wrote:

<choke>

Let me get this straight. As far as I can see, you are saying that
overtyring a bike diminishes performance, and that manufacturers do it
not so much because it looks 'good' but because they deliberately want
to reduce the handling qualities of their product so as to discourage
gormless customers from over-reaching their abilities.

You must be talking about manufacturers in some other dimension.

Moike