Bathurst 1000

In aus.motorcycles on Sat, 24 Oct 2009 03:00:24 GMT

News to me really. As there's absolutely no bloody doubt when you
*ride* one that the action is above 5k.

Sure, if you get a large enough motor it will pull more than a small
one. THe Norge will pootle along happily enough at low revs and will
even acellerate from there.

But nothing like it pulls from 5k. NOthing at all.

The Old Girl and the Hack Guzzi (one an 850 one a 950) are quite
simialr although they both have holes at around 4k for some reason so
it disturbs the seat of the pants feeling. But still the fun for both
is above 5k.

Was so on the small blocks I've ridden too.

Wheras on the long stroke pommy bikes (singles not twins I've only
started a Vincent not ridden one) they didn't have much difference
between low and middle.

The Devil now it has a decent carb is all midrange..

Zebee

 

Yep; the K100's certainly torquey all right.
http://www.ibmwr.org/ktech/dyno-update/index.shtml

Yet the humble, air-cooled, carby R100 develops more torque and from
1500rpm lower.
http://www.bmwmoa.org/forum/showthread.php?t=34800

 

Lars Chance wrote.

You can't directly compare figures from one dyno to another, whilst they
all quote direct torque they use different methods and a bike measured
on one type of dyno will get a different result on a different type of dyno.

Annoying I know...



G-S

 

You must be a Hammo artefact given the continual careful missing the
point to still try and "win".

I said
"The
4cylinder I replaced with my current twin had oodles of "low down
don't have to go looking for it grunt". My current twin has it's
torque peak further up the rev range than the 4 did. In fact the 4 had
probably half as much again grunt anywhere in the rev range as the
twin does. "

The Bandit 1200 4 cylinder referenced above had oodles more grunt -
it's peak torque was pretty flat from down around a thousand rpm right
through to a relatively low redline for a 4 (errmm 9-10 grand mebbe ?
I forget now). Definitely a lot more across the more - hence the
"probably half again more" - that's seat of the pants - but if as I"m
sure you will - you dig up the dyno chart I wouldn't be at all
surprised if it was more than that. It was a tractor of a motor.

Lastly, before you wave it around triumphantly, you'll note the above
quote didn't claim to be a comparison of comparable motors - that is
in fact exactly the point - the closer to under square you go the
lower the HP, the higher the torque (and yes, torque or turning force
is "grunt" as felt at the seat of the pants) it's why Hogly only
release torque figures (because the engine config means the HP numbers
are really sad), and similarly why a number of big (>600cc) singles
put out HP numbers less than some (4stroke) 250s.

Just because some twins display the characteristics you like doesn't
mean it's a function of the number of cylinders any more than the fact
that some redheads are scary psychos means that redheadedness causes
scary psycho behaviour (correlation not equalling causation and all
that).

JL

 

So what you're basically saying is that you were comparing an apple with
an orange and the whole post had nothing to do with the discussion to
which you replied?
....... and you called ME stupid?

 

Yeah, low blow, JL. I'm with Elsie.

Post some dyno graphs or something......

Oh, all elephants are grey, but not all grey things are elephants would have
been better than the redhead example.

Hammo
Going for science rather than seat of the pants....though that can depend on
the pants.......

 

Hang on; I thought I WAS you?
Bugger. That means I must be Johno then.

 

9500 I think, I forget too.

A Bandit 1200 has more low down torque than any twin I've owned or
ridden with the exception of an M109.


G-S

 

No. But well done for being predictable.

<speaking very slooooowly for the denser members of the class> The
power characteristics you like are unrelated to the number of
cylinders and totally related to the engine config.

I didn't actually - I provided that as one of the two possible
options. However you're starting to convince me that was the correct
choice.

JL

 

Yeah undoubtably - you trained him well If he's not you of course

Awww, I was gentling tickling for a thread diversion there - both
Betty and Toosmoky can usually be incited on that topic

You and I both know that's a diversion, in your best tradition.

I'm pretty sure you KNOW the science:
"Low down grunt" aka "high levels of torque at the bottom of the rev
range" is a function of engine config - long stroke motors with
(comparatively) fewer smaller valves, narrower exhausts and narrower
inlet tracts will provide more torque down low in the rev range at the
expense of HP at the top end of the range when you compare two engines
with the same number of cylinders and same capacity.

The number of cylinders is irrelevant to the engine torque/hp trade
off.

For the same capacity and stroke a 4 will have smaller pistons than a
twin. That config will leave the 4 with more torque down low than the
twin as it will be more under square. There's a physical limitation on
max piston speed with current metallurgy so the usual trade off is to
make the 4 closer to over square so you can rev it higher - torque
goes down and HP goes up with the rev limit (in simple terms - there's
more to it than that). The general outcome for non sports bike is a
bit more of both than a twin for the equivalent capacity and stroke.
For sports bikes a lot more HP and about the same torque.

JL

 

Ditto in my opinion, noticeably more than a 2004 Guzzi Le Mans 1200
twin in my opinion ( I rode them back to back at the time) and I would
think the Guzzi is closer to the torque side of the trade off than the
HP side (although the newer 4V head would def be a move back towards
max HP)

JL

 

Is there a reason you keep explaining the *blindingly obvious* like it
has some sort of relevance to the thread JL?
Blind Freddie's deaf 4yo knows that long-stroke is a factor in
torquiness.
Here; let me help you with some more fascinating revelations:
Water is wet.
The sky is blue. (1)
Fire is hot.
Nigerian emails are sometimes dishonest and
V-Twin motorcycles almost always have more low-down grunt than
equivalent 4cyl motorcycles (despite the seemingly collective
aus.motorcycles delusion to the contrary).

 

Right so now you finally admit that you were carefully ignoring the
bleeding obvious while trying to prove a untenable position.

JL
Yes I kept explaining the bleeding obvious ever yet more simply
because you were making it clear you were struggling to get it (or
pretending to)

 

You're getting silly now JL. I was *ignoring* your obvious because it
was irrelevant. No-one had questioned anything about engine design
affecting torque and no one has expressed any interest in it at all
(except yourself) so it *remains* irrelevant.
No one has mentioned fuels yet either; are you going to get all
hysterical and dribbling over them next?

 

I can't find a LeMans 1200 (do they even exist?) but the 1200 Griso
(with the 4V head)
http://www.motorcycle-usa.com/PhotoGallerys/xlarge/09_hd_guzzi.jpg

leads the 1200 Bandit until about 3700 then falls into a rather large
hole just as the Bandit starts coming on strong
http://www.factorypro.com/images/dyno_chart_s7410.jpg

The BMW R1200R kills the Bandit all the way though
http://www.webbikeworld.com/BMW-motorcycles/bmw-r1200r/r1200r-torque-horsepower.jpg
(Nm -> foot-pounds is about .74 so 82Nm is 60 and 117Nm is 86)

 

Yep; the K100's certainly torquey all right.
http://www.ibmwr.org/ktech/dyno-update/index.shtml

Yet the humble, air-cooled, carby R100 develops more torque and from
1500rpm lower.
http://www.bmwmoa.org/forum/showthread.php?t=34800

 

Sorry for the repost people.

 

I'd be willing to just settle for your own confession of being stupid.
But did you have to praise JL for supposedly making that claim on your
behalf?

 

A couple of points.

I mentioned in an earlier post that you can't directly compare results
from one dyno with another dyno because they aren't calibrated.

Secondly you are ignoring gearing, the Bandit is stronger at slower
speeds because it's got a lower first gear.

How do I know?

Well I currently ride and own a 1200 Moto Guzzi and I've owned 3
separate Suzuki Bandit 1200's (although at the moment I have a Suzuki 1100).

Believe me, the Bandit DOES have more torque down low and will pull away
from the guzzi at any speed you care to name.

But the Guzzi FEELS much nicer



G-S

 

In aus.motorcycles on Wed, 28 Oct 2009 20:11:50 +1100

And looks nicer too!

I also note that pretty well everyone who rides the new 4V Guzzis
says they lack down low.

Zebee