This is probably the most common question asked on this forum – am I too tall or too heavy for a 250cc bike.
If it is comfortable to sit on for 20 minutes in the dealership, then it isn’t too small for you. As a general rule, 250s fit a much larger body range than people expect.
And to address your specific question, are you too heavy?
Are you too heavy for really fast pull aways in traffic? Are you too heavy for instant passing on the highway?
On a 250, neither of those are really part of the equation anyways.
Strictly speaking, you are not too heavy for any bike until you are above it’s load capacity. I can’t speak for the cruisers, but the load capacity on a Ninja 250 is 330 pounds (almost the same weight as the bike itself).
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Okay, so now I’m gonna go on a bit of a ramble (and play with numbers – feel free to ignore this next bit, it’ll make physics majors squirm)… how slow is a slow motorcycle?
For comparison, I’m going to list some 0-60 times for well known cars (these are all from memory, with some help from wikipedia, so they could be wrong):
1965 Inline 6 Mustang – 13 seconds
2004 V6 Hyundai Tiburon (180hp, 3000 lbs) – 7.5 seconds
2004 V6 Mazda 6 (210hp, 3400 lbs) – 7.1 seconds
2005 I4 Imprezza WRX (227hp, 3085 lbs) – 5.2 seconds
2000 V8 Firebird (305hp, 3440 lbs) – 5.0 seconds
2008 V8 Mustang (300hp, 3500 lbs) – 5.0 seconds
2000 I2 Ninja 250 (35hp, 350lbs (with fluids) + 150lbs rider) – 5.7 seconds
2000 I2 Ninja 500 (52hp, 410lbs + 150lbs rider) – 3.7 seconds
So the Tib gets 16.6 lbs/hp
the 6 gets 16.1 lbs/hp
the wrx gets 13.6 lbs/hp
the bird gets 11.3 lbs/hp
the stang gets 11.6 lbs/hp
the ninjette gets 14.2 lbs/hp
and the mild ninja gets 10.8 lbs/hp
(Most family cars have a time somewhere between 8 and 13 seconds these days, all of the above cars are more than fast enough to get you into a lot of trouble with the law)
Now, this is all very rough, because really, Torque is what accelerates you, and tires dictate how much of that power can actually be used. (Hence why the new Stang is as fast the older lighter firebird) But, these numbers are easy to get ahold of, and provide a good generic comparison. And it is part of how my local Auto X organization figures out classes for cars, so if it is good enough for them…
Having roughly 16-17 lbs/hp for a car gets you in the low 7 to low 8 0-60 times. This holds true if you look back to older cars like the 85 RX-7 and the 85 Prosche 944 (non turbo versions) which each had weights and times in this area.
Having in the 10-11 lbs/hp range gets you up close and personal with the 5 second range. The WRX which can do a really hard launch thanks to its all wheel drive, also gets close to that magic 5 second number, but in rolling starts, behaves more like you’d expect, with acceleration somwhere between the big V8s and the more mundane cars.
Now, with bikes, we see that for a similar lbs/hp range, we get better acceleration than for cars. We also see that even the lowly ninja 250 is in fact pretty quick by street standards. And the ninja 500 is downright fast (for reference, a 500hp Dodge Viper has a 0-60 time of 3.9 seconds).
Now we check to see if the math is somewhat consistent:
Using the Tib as a base (16.6 lbs/hp – 0-60 time of 7.5), we expect that the firebird will get 5.1 seconds and the Stang will get 5.2 (pretty darned close on both counts).
And for bikes, using the ninja 250 as a base, we expect a time of 4.3 seconds from the ninja 500 (no doubt, the wider tires and broader torque curve help it more than the math suggests).
So, now lets make stupid guesses at how fast other bikes are.
A ninja 250 with a 300 pounds rider would have 18.6 lbs/hp giving us a guessed 0-60 time in the mid 7 seconds. Still fast enough to keep up with rice rockets and family sedans putting the pedal to the floor.
A rebel 250 (17hp, 330 pounds with fluids+ 150lbs rider) returns 28.2 lbs/hp, giving us a 0-60 time of 11 seconds. So now we are hanging out with civic and cobalts.
This is however, where a hole in our math shines through: The Rebel makes less than half the power of the ninja, but makes almost as much torque (Ninja 250 makes 16 lb-ft, the Rebel makes 14 lb-ft). So, the Rebel should get better than 11 second 0-60 times. And as my mother owns one, using the good old butt-dynometer I’m pretty sure it does. My butt-guess puts it in the 9-10 second range… Heck, my mother wheelied her rebel just last week!
Putting a big boy (300 pounds) on a rebel 250 gives us 37.0 lbs/hp or, again very roughly, just shy of 14 seconds to freeway speeds. While I know it’ll be faster than that – that is defintely into the “I’m not entirely comfortable with how fast she pulls” range for me.
Putting the same big boy on a Vulcan 500 (it has the same engine as the ninja, but weighs 440lbs) gives us 14.8 lbs/hp – the same range as the ninjette with a skinny guy on it. Plenty fast.
If you were skipping my mangled math, you can starts reading again
So, if I was over 250 pounds, and wanted a cruiser, I’d stay away from the 250s and move up to a 500. More than 10 seconds to reach freeway speeds is just longer than I’m comfortable with (but then, I’ve owned both the Tib and the Mazda 6 above, so I’m used to getting on my freeways pretty fast). Of course, if you never plan on taking the bike on the freeway, that changes things.
Anything more than 50hp though (the 750cc+ cruisers) really is way more power than you need, no matter how much you weigh.
If I was over 250 pounds, looking for a sport bike, I think the Ninja 250 would still be fast enough for my wants. Moving up to a Ninja 500 would certainly get me going faster, though the bigger bike is more work to learn on.
If I was under 250 lbs (which I am) I’d feel pretty comfortable with the power from any 250cc engine (which I do).
Sorry for the rambling.