Getting my cruiser to wheelie

 

Hey everyone,

I've been riding for years, and have never been overly adventurous
(stunts and crap), but really want to make my current bike do a
wheelie... hell, even a 1' high one. . .  the problem is that my
sportbike-riding friends laugh and say it can't be done.

I have a 2001 Suzuki Intruder 1500 LC.   It DOES have a huge engine
and lots of tork, but, god... that front wheel is, like, 5' out in
front of me when I'm riding.  The bike weighs around 1,150 pounds with
me on it.

What is the general thought.... can it be done?  If so, what would the
proceedure be?  Quickly releasing the clutch and giving it gas just
makes a lot of noise, the front shocks barely raise up.


James, Port Orchard, WA, USA

 

wrote:


My riding buddy used to pop rebound wheelies on his 1100 Virago. He
didn't care, he was behind in his payments and knew the bike was going
to be re-possessed...

He would take advantage of the fact that a cold engine has more
compression, and he would start rolling and then bounce the forks up
and down by opening and closing the throttle and he would use the
recoil of the springs to get the wheelie started as he gave the engine
full throttle in first gear.

But wheelies don't necessarily prove that a motorcycle is powerful,
they show that if the wheelbase is relatively short and that the
center of gravity is relatively high, a motorcycle will wheelie at a
moderate rate of acceleration.

Back in the 1960's, there were kids on 50cc Honda trailbikes doing
wheelies in parking lots everywhere because the center of gravity was
so high and the wheelbase was so short.

And the rider often weighed as much as the motorcycle, so standing up
on the footpegs and hanging their butts over the tail light while
popping the clutch would get the front wheel off the ground,
especially if they used their larger trail sprocket.

Long wheelbase cruisers are heavy and have a low center of gravity and
that works against wheelies. Bikes with a low center of gravity will
tend to spin the rear wheel instead of doing a wheelie.

The minimum acceleration required to do a wheelie is found by the
formula,

g = (% weight on front wheel / 100) X (wheelbase / height of center of
mass)

As used in this formula, g is dimensionless, it stands for a decimal
percentage of the acceleration of gravity.

So, suppose the motorcycle has 33% of its weight on the front wheel,
has a 5-foot wheelbase and the center of mass is 2 feet above the
ground.

g = (33/100) X (5/2) = 0.825 g

If you reduce the weight of the front wheel to 25% of the total weight
of the bike, g = (25/100) X (5/2) = 0.625 g

Now, it's a well known fact that powerful sportbikes will accelerate
to 60 mph (88 feet per second) in 3 seconds or less.

Acceleration = velocity / time, so 88/3 = 29.33 feet/sec

29.33/32.2 = 0.91 g. It's a well known fact that large sportbikes with
short wheelbases and high centers of mass won't keep their front wheel
on the ground under vigorous acceleration.

So, how long does it take for your Suzuki to reach 60 mph in first
gear, maybe 5 seconds?

88/5 = 17.6 feet/sec or 17.6/32.2 = 0.55 g.

A little over half a g is the best acceleration your Suzuki can
manage. Sportbikes can accelerate twice as fast.

So, if you could reduce the amount of weight on your front wheel to
20% of the total weight of the motorcycle and rider,

g = (20/100) X (5/2) = 0.50 g

 


Thanks for all the answers and math, Morrgaine!  I sort of chuckled
about your estimate of reaching 60mph in 5 seconds in first gear
though... I should measure it once, but I think the MINIMUM would be
3rd gear, and it's probably closer to 7 seconds.... for 1500cc's it's
a slug.

I love my bike all the same, and in reality, TWO wheels on the ground
are just fine with me.

Thank you,

James









wrote:

 

wrote:

Or if you can't follow all that faked up longhair math crap, you could
apply solid rocket boosters to each front fork leg.

The angle of "A" (fork leg), also known as rake applied to the newtons
of energy produced by "B" (rocket boosters) X the stupidity of the
proposal of the act = "C"- a new bike which you will need if you want
to do wheelies.

 Try it, it works!

 

Bike Guy Joe wrote:

Between this and the discussion of lowriders in another thread I'm
flashing on big cruiser with air shocks in front so that it can be
"hopped" into wheelie position.


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