Which Brakes? Avid Mechanical Disc? Magura Big or Marta HydraulicDisc?



P

Paul Boyd

Guest
On 29/08/2007 19:58, coyoteboy said,

> Lots of the top end systems are open - its how they get automatic pad
> wear adjustment. Certainly most of the systems I've seen on the trail
> have been open - closed just makes no sense - need to adjust pad on the
> fly and back it off if you heat the caliper up.


OK - I didn't realise the first bit, but the second bit? That's why
Shimano have the bladder in the lever - so that as the fluid expands the
air in the bladder compresses to compensate. Perhaps I'm
misunderstanding what is meant by a closed system.

> And if you want to bleed them, which isnt really needed for a decade at
> a time, you just lob a piece of hose on the nipple, take the top off the
> caliper and squeeze, undo, tighten, release a few times and its done -
> not even as complex as replacing a cable!


Surely that's the same for any system, except I assume you mean take the
top off the lever?

--
Paul Boyd
http://www.paul-boyd.co.uk/
 
C

Clive George

Guest
"coyoteboy" <[email protected]> wrote in message
news:[email protected]

> Many disc manufacturers use mineral oil like maggies so it doesnt absorb
> water, but even so the DOT based fluids never reach the sort of heat
> required to "wet boil" in anything other than extreme downhill conditions.


Remember I'm using ours on a tandem...

> I just dont understand where this idea that hydro discs are "high
> maintenance" comes from.


I'm not sure where you get it from either. I'm talking about relative to the
rim brakes.

But if you consider this experience -

Rim brakes : Worked out of the box, zero maintenance required of the
internals in 10 years

Discs : Need bedding in, needed bleeding to make the back brake work,
pistons misbehaving a little in 2 years. And of course there's the way the
disc pads can't cope with oil on them :-( (got sintered now, so you just
need to let the smoke out to fix this - but the rims don't suffer in this
way)

them you might understand where I'm coming from.

cheers,
clive
 
C

coyoteboy

Guest
Paul Boyd wrote:
>(can you even still get open systems?), and they just keep


Lots of the top end systems are open - its how they get automatic pad
wear adjustment. Certainly most of the systems I've seen on the trail
have been open - closed just makes no sense - need to adjust pad on the
fly and back it off if you heat the caliper up.

> working. They may need to be bled once every so often, but cables need
> maintenance more than once every so often. All brakes need pads/blocks
> replaced periodically, so I'm genuinely interested in why you think
> discs aren't "fit and forget".


And if you want to bleed them, which isnt really needed for a decade at
a time, you just lob a piece of hose on the nipple, take the top off the
caliper and squeeze, undo, tighten, release a few times and its done -
not even as complex as replacing a cable!
 
C

CoyoteBoy

Guest
On 29 Aug, 19:19, Paul Boyd <[email protected]> wrote:
> On 29/08/2007 19:58, coyoteboy said,
> OK - I didn't realise the first bit, but the second bit? That's why
> Shimano have the bladder in the lever - so that as the fluid expands the
> air in the bladder compresses to compensate. Perhaps I'm
> misunderstanding what is meant by a closed system.


Yup, i think thats where the confusion comes in - a closed system is
one where the entire volume of the fluid is under pressure when the
lever is squozed :) An open system has a reservoir (be it a bladder or
a cup etc). A closed system is like the magura HS33 - there is no
reservoir meaning if the system heats enough to make the fluid expand
you have to back off either the lever position or a separate adjuster
(just another piston essentially) to stop the brakes binding. The open
system relies on seal flex to pull the pistons back and pushes spare
fluid back into the reservoir, but as the fluid heats up it gets
pushed back into the reservoir naturally and doesnt affect the piston
position.

> Surely that's the same for any system, except I assume you mean take the
> top off the lever?


Yes, it is for any hydro system (I wasnt disagreeing with your post, I
was confirming). Maggies (HS33) are harder than most to bleed when
needed due to the fact that they are closed and you need to remove
every last bubble from the lever to prevent spongeyness - this was the
main problem I had brought back to me time and time again by HS33
owners who had had a go at bleeding.

J
 
C

coyoteboy

Guest
Clive George wrote:

> That isn't "forgotten about them". I've never opened the rim brake
> internals - and they are 10 years old now.


I've replaced the magura blood after 4 years (just because I got some
for free) and it makes definite difference to pad movement feel. But
then my other HS33s had their oil replaced with chip oil when i ripped
the hose out of them on holiday and that works just as well to this day.
I think the point is that there is no need to bleed a disc, as there
isnt with a HS33. Many disc manufacturers use mineral oil like maggies
so it doesnt absorb water, but even so the DOT based fluids never reach
the sort of heat required to "wet boil" in anything other than extreme
downhill conditions. People often bleed hydro discs because they assume
they "should" - there is no need.

>> All brakes need pads/blocks replaced periodically, so I'm genuinely
>> interested in why you think discs aren't "fit and forget".

>
> Compared to the magura rim brakes, they aren't IME. That's it.


IME (I "maintain" 2 sets of HS33s - one pair of Raceline D and one
newer, 2 hope DH4s, 1 hope mini, 1 hope mini mono, a pair of louise FRs
and have direct contact with owners of cheapo cable and shimano XT discs
and have plain old Vs on the old machine that gets no use these days)
they are comparable to maggies - in fact less effort required, and less
problems with rim damage effecting them. The worst thing is the
occasional bouts of squeel, but then the HS33s get that with the wet
weather pads from time to time too. I managed to melt a set of HS33 pads
to the rim in the alps (DH course) and have blue'd the rotors on the
DH4s and mini several times. I just dont understand where this idea that
hydro discs are "high maintenance" comes from. I'd not replace my
maguras on my trials bike because the discs just dont bite as
aggressively at low speed, but then the maggies dont control as well at
high speed so I wouldnt use them on my MTB anymore - even with the
maggies I've run into the back of my brother (DH4s) on numerous
occasions due to the poorer high-speed braking (which is still
blisteringly good IMO).
 
C

CoyoteBoy

Guest
On 29 Aug, 19:13, "Clive George" <[email protected]> wrote:
> "coyoteboy" <[email protected]> wrote in message
> Indeed. If you get your brakes hot, closed doesn't work. And I got that on
> hardly any hill at all. But then this was on a tandem.


Tandems are a tad of an issue being essentially twice the energy being
dissipated as the brake was designed for. Must say I've never worked
on them but I cant see any reason why the mechanics of the work is any
different.

> Hmm. I'm guessing you've never bled a set of Hopes then. I've done one end
> of ours, and it was a right pain, even with the bleeding kit.


Yup, hopes were my first ever disc, never had a problem, never had the
bleed kit. I've shortened hoses on them a few times between frame/fork
changes on other peoples bikes and I didnt find bleeding them an issue
at all? Certainly easier than magura HS33s. But then I'm used to
bleeding the brakes on my car - maybe that helps? I didnt think it
could possibly be considered a difficult task?

> One problem is them using DOT brake fluid. I _hate_ DOT brake fluid. (My car
> doesn't use it either...). It needs changing in a way that the mineral oil
> doesn't - 2 years, not 10.


No it doesnt - this is where you are mistaken. It requires changing
only if you are going to overheat it - recommendations of 2 years are
set by car standards (which were thought up decades ago when brake
systems were considerably more agricultural and allowed moisture
absorbtion easily) and our brakes do not reach the heat of a car
caliper (though, of course, a tandem may get closer). Even on a DH run
in the alps myDH4 /calipers/ rarely got hot enough to burn with me
(15stone, the bike at 40lbs and speeds of 40mph). The wet boil temp of
DOT4 is 155 degrees C - if you get your calipers to anywhere near 155C
i bow down to your superior braking! (or pass you on the way down :),
most braking is un-necessary if you pick the right lines) I've yet to
hear of anyone boiling fluid in a bike brake - fading organic pads due
to outgassing, yes (solved by choosing a correct pad material from the
start). On a car - yes. The primary reason for bleeding DOT fluids is
to remove the fluid which has absorbed water (hence the wet boil
temps) and return "dry" fluid which boils at 240C. I actually change
out my fluid for DOT5.1 if I change the cable routing etc and have to
bleed, much the same as I'd change the cables on a cable brake or
change the fluid on the maggies.

> I guess if I had Magura disks, some of my complaints may go away. (Shimano's
> a no-no based on the use we give them).


Yes, I agree you wouldnt want shimano discs on a tandem - too
lightweight IME.

> The reason I say the discs aren't fit and forget in the same way as the
> magura rims is that I have had to do this sort of **** on them, whereas the
> rims have been sealed since I fitted them 10 years ago, and have never given
> any problems.


Why did you have to bleed it? It just isnt necessary. And as
mentioned, it couldnt be an easier task to blow through new fluid, not
like when you get really bad bubbles in and have to get shut of them
too. I'll do a youtube vid soon, maybe I have some magic technique I
didnt know was magic?

> There is another question though : is it worth the hassle? And the answer
> for the MTB tandem is definitely yes. Can't tell for the road tandem since
> nobody makes suitable hydraulic discs...


I'm missing where the hassle comes in TBH - which was my point from
the start - hydros are the most fit and forget items on any bike I've
owned or maintained!
 
P

Paul Boyd

Guest
On 29/08/2007 20:12, CoyoteBoy said,

> Yup, i think thats where the confusion comes in - a closed system is
> one where the entire volume of the fluid is under pressure when the
> lever is squozed :) An open system has a reservoir (be it a bladder or
> a cup etc).


I was totally confused, wasn't I? :)

--
Paul Boyd
http://www.paul-boyd.co.uk/
 
C

CoyoteBoy

Guest
On 29 Aug, 19:24, "Clive George" <[email protected]> wrote:
> "coyoteboy" <[email protected]> wrote in message
>
> news:[email protected]
>
> > Many disc manufacturers use mineral oil like maggies so it doesnt absorb
> > water, but even so the DOT based fluids never reach the sort of heat
> > required to "wet boil" in anything other than extreme downhill conditions.

>
> Remember I'm using ours on a tandem...
>
> > I just dont understand where this idea that hydro discs are "high
> > maintenance" comes from.

>
> I'm not sure where you get it from either. I'm talking about relative to the
> rim brakes.


You are suggesting that hydro discs need frequent maintenance and are
more complex than the rims - im suggesting they arent.

> But if you consider this experience -
>
> Rim brakes : Worked out of the box, zero maintenance required of the
> internals in 10 years
>
> Discs : Need bedding in, needed bleeding to make the back brake work,
> pistons misbehaving a little in 2 years. And of course there's the way the
> disc pads can't cope with oil on them :-( (got sintered now, so you just
> need to let the smoke out to fix this - but the rims don't suffer in this
> way)


It takes a short ride to bed a disc - 10-20 miles - if it takes longer
you have the caliper mis-aligned. Maggies also need you to carefully
align the pads or you get squeeks and the pads wearing unevenly. Why
would you have to bleed the rear? Presumably to fit to the frame- the
same with any hydro brake such as HS33? Why (and how) are the pistons
misbehaving - this again suggests you have the caliper misaligned to
start with - the pads pushing at odd angles tend to get jammed and not
retract well? This is totally contrary to my experience with well set
up discs, but i did get to practice on a few customers bikes before I
could afford my own! No, pads cant cope with oil on them, but then
maggie pads cant cope well in mud and ice. If you get oil on them then
thats carelessness, not the brake at fault - at least when out on the
trail a disc will work when drowned in mud and ice (better in most
cases) while maggies tend to tail off a little, especially at speed
again. If you ride in any real snow you'll find maggies get a nice
smooth layer of snow-ice packed onto the rim eventually - this isnt
fun - discs remain hot and prevent this.
 
C

Clive George

Guest
"CoyoteBoy" <[email protected]> wrote in message
news:[email protected]
> On 29 Aug, 19:13, "Clive George" <[email protected]> wrote:
>> "coyoteboy" <[email protected]> wrote in message
>> Indeed. If you get your brakes hot, closed doesn't work. And I got that
>> on
>> hardly any hill at all. But then this was on a tandem.

>
> Tandems are a tad of an issue being essentially twice the energy being
> dissipated as the brake was designed for. Must say I've never worked
> on them but I cant see any reason why the mechanics of the work is any
> different.


No, the mechanics are the same.

>> Hmm. I'm guessing you've never bled a set of Hopes then. I've done one
>> end
>> of ours, and it was a right pain, even with the bleeding kit.

>
> Yup, hopes were my first ever disc, never had a problem, never had the
> bleed kit. I've shortened hoses on them a few times between frame/fork
> changes on other peoples bikes and I didnt find bleeding them an issue
> at all? Certainly easier than magura HS33s. But then I'm used to
> bleeding the brakes on my car - maybe that helps? I didnt think it
> could possibly be considered a difficult task?


Maybe the mono levers are more of a pain then. Certainly the bits which are
similar to a car were no problem whatsoever - but the reserviour is
significantly more hassle, being all tiny and fiddly and having no spare
capacity.

>> One problem is them using DOT brake fluid. I _hate_ DOT brake fluid. (My
>> car
>> doesn't use it either...). It needs changing in a way that the mineral
>> oil
>> doesn't - 2 years, not 10.

>
> No it doesnt - this is where you are mistaken. It requires changing
> only if you are going to overheat it


Or if it gets wet. The mineral oil I have sitting around won't suffer this -
but the container of DOT fluid may well do :-(

> The wet boil temp of
> DOT4 is 155 degrees C - if you get your calipers to anywhere near 155C
> i bow down to your superior braking! (or pass you on the way down :),


Probably both. I'm not a fantastically confident descender, so will use the
brakes, and as you noticed I can put twice the energy into them. (Actually
it's potentially more than that, since I can't endo...)

>> The reason I say the discs aren't fit and forget in the same way as the
>> magura rims is that I have had to do this sort of **** on them, whereas
>> the
>> rims have been sealed since I fitted them 10 years ago, and have never
>> given
>> any problems.

>
> Why did you have to bleed it?


Because there was air in it. I think the people who put the tandem-length
pipe on it got it wrong - that was Hope BTW.

> It just isnt necessary.


Except it was...

> And as
> mentioned, it couldnt be an easier task to blow through new fluid, not
> like when you get really bad bubbles in and have to get shut of them
> too.


Like I did?

>> There is another question though : is it worth the hassle? And the answer
>> for the MTB tandem is definitely yes. Can't tell for the road tandem
>> since
>> nobody makes suitable hydraulic discs...

>
> I'm missing where the hassle comes in TBH - which was my point from
> the start - hydros are the most fit and forget items on any bike I've
> owned or maintained!


> If you get oil on them then thats carelessness, not the brake at fault


Actually, it's the fork air seal failing and dumping the oil on the brakes.

The sensitivity of the brakes to oil is a definite downside - with care, the
problem can be avoided, but I'm sure you'd agree the it would be better if
it wasn't there in the first place.

I think my discs are set up fairly well - they're definitely straight (I
spent a while getting that right when first installing them, and I'm not
completely mechanically inept.)

cheers,
clive
 
S

squeaker

Guest
If you do go Avid mechanical, go BB7 not BB5. The differences are
deeper than 'no outer pad adjuster', IMHO.
 
D

David Damerell

Guest
Quoting Marz <[email protected]>:
> Sounds like your consensus views are coming from folks who can't
>afford hydraulic brakes and therefore **** 'em off.


Lesson one, children; why ad hominems are a logical fallacy.
--
David Damerell <[email protected]> Kill the tomato!
Today is First Sunday, August - a weekend.
 
T

Tom \Johnny Sunset\ Sherman

Guest
roger merriman wrote:
> On 29 Aug, 05:03, "Tom \"Johnny Sunset\" Sherman"
> <[email protected]> wrote:
>>
>> I can lock up both from wheels on dry pavement with the Avid mechanical
>> disc brakes on my trike. The feel is mushy compared to a good hydraulic
>> system, however.
>>

> Thing is though that locking the wheels is one thing, stopping fast
> and safely is another, my cheap hybrid can lock it's wheels, but i
> would regard is brakes as poor, in that it wouldn't stop in hurry at
> speed, while my moutain bikes will, which considering the rubber on
> the road i'd probably struggle to lock wheels up.
>
> like the other day had to do a emergency stop, squeeling of tires on
> hot road but not locking.


Can you lock the front wheel on your hybrid? An upright bicycle will
"pitch over" before the front wheel will lock on dry pavement.
Conversely, due to weight transfer, the rear wheel can be locked with
quite weak brakes (or almost no brake at the point where the wheel is
about to be unloaded).

On a tadpole trike with a low seat, braking is limited by tire traction
only. The available braking force is generally about 40% more than could
be produced on an upright.

--
Tom Sherman - Holstein-Friesland Bovinia
A Real Cyclist [TM] keeps at least one bicycle in the bedroom.

--
Posted via a free Usenet account from http://www.teranews.com
 
A

Artemisia

Guest
Thanks for all the answers, but I'm a bit out of my depth in all this
technical talk.

Might someone explain:

What is brake "bleeding" and why is it necessary (or not)?

What are maggies? HS33s? What kind is Magura Big?

What does "open" and "closed" mean?

What is a rim brake? I don't think any are on offer for my
Scorpion...?

I hope I can delegate any eventual problems and adjustments to my bike
mechanic? Ditto for eventual maintenance? If I buy the brakes as part
of my initial setup, do I still have to do all sorts of adjustments
and setups on my own? See, I don't feel confident to tackle all this
new science and don't have time to take a qualifying degree in bike
maintenance (that my have to wait till I retire!).

On another tack: does a recumbent trike actually have _3_ brakes,
including the one aft? I think the system I'm going for (I mean the
Magura Big) includes an Avid v-brake on the back which also acts as a
parking brake with a velcro strap. Wouldn't that on its own
significantly increase stopping power in relation to 2-wheelers?

I'm thinking I probably will go with the Magura Big setup. The group
is telling me it's worth the extra expense. OTOH I can probably pass
on the DT Swiss suspension thingey and make do with the Busch & Muller
bottle dynamo with standlight, rather than the SON hub dynamo.

Saturday I go speak to Darth Delano at Rando-cycles. I hope he too may
have some advice for me.

Thanks to all for the lively and informative discussion.

EFR
Ile de France
 
A

Alan Braggins

Guest
In article <[email protected]>, Artemisia wrote:
>Thanks for all the answers, but I'm a bit out of my depth in all this
>technical talk.
>
>Might someone explain:
>
>What is brake "bleeding" and why is it necessary (or not)?


http://en.wikipedia.org/wiki/Brake_bleeding

>What are maggies?


Magura brakes.

> HS33s?


A model of Magura rim brake

> What kind is Magura Big?


Disc.

>What does "open" and "closed" mean?


Whether the reservoir of hydraulic fluid in the brake system is open
to the atmosphere or has an airtight seal.


>What is a rim brake?


A brake where the pads act on the rim of the wheel - a "normal" bike
brake that isn't a hub or disc brake.


>I hope I can delegate any eventual problems and adjustments to my bike
>mechanic? Ditto for eventual maintenance?


Yes, assuming a competent mechanic. A decent shop will sort the initial
setup for you too.


>On another tack: does a recumbent trike actually have _3_ brakes,
>including the one aft?


Some do, but under heavy braking the front wheels have almost all the
weight on them anyway, so a brake on each front wheel gives you the legally
required two systems and is as effective and less complicated.
 
P

Peter Clinch

Guest
Artemisia wrote:

> Might someone explain:


Alan pretty much has, but a couple of extra notes...

> What is brake "bleeding" and why is it necessary (or not)?


While this isn't necessary with mechanical cables as there's no fluid to
bleed, mechanical cables have their own problems and in practice need to
be replaced periodically too, probably more than hydraulics need bleeding.

> What are maggies? HS33s? What kind is Magura Big?


Note that HS-33s aren't relevant on the Scorpion as it'll be discs only,
so if it's on the price list for a Scorpion it will be a disc. HS-33s
use hydraulics rather than cables which is why they've been brought up,
to compare general characteristics of hydraulic and mechanical setups.

> I hope I can delegate any eventual problems and adjustments to my bike
> mechanic? Ditto for eventual maintenance? If I buy the brakes as part
> of my initial setup, do I still have to do all sorts of adjustments
> and setups on my own? See, I don't feel confident to tackle all this
> new science and don't have time to take a qualifying degree in bike
> maintenance (that my have to wait till I retire!).


That's why you're paying a shop, so you don't have to worry. Brakes
aren't set up in a personal way like suspension, which is ideally
something you should be able to tune yourself if you've bought a tunable
setup like the DT-Swiss on offer.

> On another tack: does a recumbent trike actually have _3_ brakes,
> including the one aft? I think the system I'm going for (I mean the
> Magura Big) includes an Avid v-brake on the back which also acts as a
> parking brake with a velcro strap. Wouldn't that on its own
> significantly increase stopping power in relation to 2-wheelers?


The back brake is really just there as a parking brake. It won't have
too much effect on your real stopping power which will be taken up
front, because as soon as you slam on the anchors all the weight will be
on the front wheels and all you'll get by braking at the back is locking
the wheel and skidding.
I think you'll be happily surprised about how much stopping power you
get on a low recumbent trike with properly specified brakes.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/
 
S

squeaker

Guest
On 30 Aug, 08:35, [email protected] (Alan Braggins) wrote:
> Some do, but under heavy braking the front wheels have almost all the
> weight on them anyway, so a brake on each front wheel gives you the legally
> required two systems and is as effective and less complicated.

And also remove the possibility of getting said trike sideways if
braking on a curve, which is probably a 'good thing' unless you are
mucking about on a loose surface (which is why KMX fit a rear brake,
AFIK).
 
P

Paul Boyd

Guest
Peter Clinch said the following on 29/08/2007 18:21:
> The feel and control is just /sooooooooo/ much better.


That's really the crux of the matter. Any brake should be able to lock
up your wheels, therefore provide more than enough raw stopping power,
but it's how you can control that power that makes the difference.

--
Paul Boyd
http://www.paul-boyd.co.uk/
 
P

Peter Clinch

Guest
Paul Boyd wrote:
> Peter Clinch said the following on 29/08/2007 18:21:
>> The feel and control is just /sooooooooo/ much better.

>
> That's really the crux of the matter. Any brake should be able to lock
> up your wheels, therefore provide more than enough raw stopping power,
> but it's how you can control that power that makes the difference.


Agreed, and IME there was a very big difference between reading about it
in theory and actually experiencing it.

I went from sceptic feeling there wasn't really anything wrong with my
brakes as they were to "Oh! *Now* I see what the point is, I think I'll
be getting some of these!" over the course of a day's riding on an
otherwise rather unimpressive demo bike.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/
 
R

Roger Merriman

Guest
Tom "Johnny Sunset" Sherman <[email protected]> wrote:

> roger merriman wrote:
> > On 29 Aug, 05:03, "Tom \"Johnny Sunset\" Sherman"
> > <[email protected]> wrote:
> >>
> >> I can lock up both from wheels on dry pavement with the Avid mechanical
> >> disc brakes on my trike. The feel is mushy compared to a good hydraulic
> >> system, however.
> >>

> > Thing is though that locking the wheels is one thing, stopping fast
> > and safely is another, my cheap hybrid can lock it's wheels, but i
> > would regard is brakes as poor, in that it wouldn't stop in hurry at
> > speed, while my moutain bikes will, which considering the rubber on
> > the road i'd probably struggle to lock wheels up.
> >
> > like the other day had to do a emergency stop, squeeling of tires on
> > hot road but not locking.

>
> Can you lock the front wheel on your hybrid? An upright bicycle will
> "pitch over" before the front wheel will lock on dry pavement.
> Conversely, due to weight transfer, the rear wheel can be locked with
> quite weak brakes (or almost no brake at the point where the wheel is
> about to be unloaded).
>

on the hybrid the the biggest danger in locking a wheel is looking
control than pitching over, it's weight means you'd really have to try,
possibly pitching your weight forward

but most uprights you really would have to try before pitching your self
over.

i'm used to mounatin bikes so i move my weight under braking so for
instance while it was close to i didn't lock the rear when i had to do a
emergency stop from about 20.

> On a tadpole trike with a low seat, braking is limited by tire traction
> only. The available braking force is generally about 40% more than could
> be produced on an upright.


thats the same of any bike, certinaly if you move your weight around.

but again locking ones brakes while sounds impressive doesn't stop you
as fast or as incontrol as braking to just within the limits of the
tires.

roger
--
www.rogermerriman.com
 
C

CoyoteBoy

Guest
On 30 Aug, 10:54, [email protected] (Roger Merriman) wrote:
> Tom "Johnny Sunset" Sherman <[email protected]> wrote:


> but again locking ones brakes while sounds impressive doesn't stop you
> as fast or as incontrol as braking to just within the limits of the
> tires.
>
> roger
> --www.rogermerriman.com


10% slippage is quoted as best accel and decel tyre slip rate
according to the motorsport boys - im not sure how or why they come to
that conclusion but IIRC its used in F1 so cant be far wrong?