liquid Vs Aircooled motorcycles

Hi Folks,

Is there any real advantages or disadvantages between air and liquid engines
in motorcycles?

I'm in the process of choosing my next bike but won't have a big budget but
will be looking for a big bike for touring and commutting with the emphasis
on touring.

I'm considering bikes with aircooling rather than liquid cooling engines.
Is this a good idea? or not?

Some of the bikes that I have in mind are getting a little old but from many
reports I've read,are good tourers of pre 2000.
Bikes such as the Yamaha Diversion 900 and the FJ1200 are 2 I've had in mind
and are aircooled.

Are aircooled bikes too prone to overheat on a hot summers day?

Are there any other suggestions for a bike like those above that could be
had for around the $5,000 mark?

I have a friend that has a liquid cooled 1200 Kawasaki and his radiator has
become useless and said he's had to park it under the carport for a good
while as it'll cost him $1200+ to have it replaced. Bloody scary I reckon!!

I'll be interested in opinions about this and hopefully will help me make a
decision either way.

Thanks in advance.

Cheers

DJ

 

Yes.

Generally, the air-cooled engines don't produce the big horsepower
numbers that the liquid cooled engines do.

They also have less "bits" to go wrong.

For commuting, you don't want the peak power business, nor do you want
the electric fan cutting in in traffic, cooking your legs, as tends to
happen with the liquid cooled bikes.

They are indeed, and good machines, too.

Not really. Not any more, and probably less than a liquid cooled bike.

regards,
CrazyCam

 

I own a Suzuki GS 500. It commutes and tours adequately for my purposes. I
have just taken it from Canberra to Narromine and back. It has been from
Canberra to Sydney and return on several occasions. I have ridden it on
very hot days, about 40 degrees C with no obvious problems.

John Dwyer.

 

For my 2 cents, I'd get whatever bike is comfy for you. If you aren't
going fo massive horsepower then either will suit. Yes, as Cam says,
there are less things to go wrong on a liquid cooled bike, but in my
25 years of riding (except the last two years - waahhhhhh!!) I've had
not a single thing go wrong with the cooling systems on any of my
bikes, and all of them have been liquid cooled.

I'd be choosing the bike more on what suits you and not worry about
the air/liquid cooling issue. Especially in modern bikes. I guess if
you were going to buy a 20 year old liquid cooled bike, there is more
of a chance of something about to give up and die.

 

Thanks guys for that info.

I've never actually heard of any major incidents with aircooled bikes but
with most of the bikes these days going with liquid cooling,I was wondering
if it was actually a better system and as some of you said, with aircooling,
theres less to go wrong.

I once had a Kwaka ER500 and it was watercooled but wasn't exactly a high
performance bike but had no cooling or other issues with it. It wasn't a bad
little tourer either except for the constant light buzzing vibration through
the handlebars that sent my throttle hand to sleep after a while. It used 13
litres for 300kms of highway speeds averaging 100-120kph (cops & Cameras
everywhere on the New England hwy) packed to the brim with luggage for a 9
day holiday.
It had close on 400km range incl. reserve on a 17 litre tank.

Another question has come to mind, some of the older tourers as the ones
mentioned and similar have high kms on them, sometimes well over the 100,000
mark. If bought for a reasonable price considering km's travelled,would it
be too expensive to have the engine and gearbox overhauled if the frame and
paneling etc is in good nick? around what would it cost to have something
like a 900-1200cc 4 cyl bike reconditioned?

Thanks again for your advice and imput, greatly appreciated.

Cheers

DJ

 

Squariels, and all those Harley lookalikes that insist on placing an
aircooled cylinder directly behind another, and then trying to get max HP
out of it.

Theo

 

In aus.motorcycles on Sun, 17 Feb 2008 12:54:47 +1100

Heaps....

Depending of course on what reconditioned means. Might get away with
new rings if it is blowing smoke but new top end is very expensive.
May well need a clutch. Various bearings - wheel, steering head.
What condition are the forks in? How's the gearbox?

So much will depend on what is wrong with it.

Zebee

 

Lucky me, I have the best of both worlds, an air-cooled bike with an
electric fan which cuts in and cooks my legs.

Nev..
'07 XB12X

 

Assuming some sort of non-liquid oil of course!

 

You'll find that most in-line 45º air-cooled twins have a lower compression
ratio in the rear cylinder. Why do you think they would do that?

Ariel fours didn't have overheating problems? It was the primary cause of
their demise. The TX750 was better cooled.

Theo

 

Mine certainly doesn't , do you have a cite ?

Mine didn't unless thrashed .
Ok I guess it often did
It was the primary cause of

 

Not on line, but I've read it several times in different publications on
motorcycle and other engine design. Apparently it's quite common to have
different compression ratios in cylinders. eg, my 230S Merc has the cast
iron straight six. Compression ratio is 10:1. If you read the workshop
manual you find that cyl # 1 is 9.5:1, #2 is 9.75:1, the rest are 10:1. This
is because the front end of the engine is hotter in operation to the back
end, so they compensate by not working the front end as hard.

Cheers
Theo

 

In the downloadable manual for the 230s it fails to mention differing
compression , my 450Sle all has the identical compression on 8 cylinders
but then the 230 is sorta the corolla of the breed and certainly all
my Jags run the same comprssion in the six cylinder motors.

I really would like to see a cite/manual with mention as the internal
difference required to result in these differences would I expect
introduce a whole new and interesting set of harmonics and strains in
the general running of the motor would it not ? . One would think the
right engineering solution would be to effect proper cooling rather than
altering compression ?.

 

Huh?

He'll have one of the ZZ-R1200, ZRX1200 or the ZX-12R. The former two
have radiator mesh shields from the factory, and the bare alloy
radiator on the 12R is a bigger version of the one that's now done
85,000km on my ZX-6R and continues to keep the coolant temp at 69deg-C
when the bike's moving despite the patch in the bottom middle where
the cooling grilles have been hammered flat by bouncing rocks...

You say his radiator has been "made useless". What does that mean,
exactly? What happens to the bike when he takes it out?

While the $1200 replacement cost is feasible for dumb-fucks who buy
over the parts counter at a dealership, secondhand rads can be had
from Ebay for a couple of hundred bucks, and most radiator places will
have a fairly successful go at reconditioning a bike radiator for a
similar price.

2007 is about a quarter-century too late to distrust this newfangled
liquid-cooling stuff on motorbikes. With a five-grand budget for a big-
bore tourer, you're gypping yourself for choice if you give preference
to air-cooled bikes. That said, the XJ900 Diversion would probably be
one of the better choices if you can't tolerate even a modicum of a
bent-over riding position, such as you'd get on a bike like a ZZ-
R1100, VFR750 (go ahead, try and kill one of those liquid-cooled bikes
without getting a 100-foot dropoff involved) or similar.

 

Ahh, sorry. I'm talking about the 60s six cylinder models, not the current
stuff.

I have a 230S and a 220SE Manual and they both give lower figures for the
first two cylinders. Let's face it, it's not something you're going to make
up.

Theo

 

Yes I know what they are being an ex owner..

where did I say that ?
just seems an odd way to fix a simple problem.

 

Luxury . my old 57 small window didn't and made a whole 40 HP before we
re-powered it with a Chev .

 

I meant, not something someone makes up and prints in the manual. It's not
even something most people would think of. I remember the first time I read
it saying "What the...."

Theo

 

I thought they still had the 1100 cc 36hp motor then. My first beetle was a
60.

Theo

 

yup 36 but heads ported and a cam , then it broke the crank