Cycle Forums: Motorcycle and Sportbikes Forum banner

1 - 20 of 22 Posts

·
Registered
Joined
·
24,114 Posts
Discussion Starter #1
This guy kept wanting to race me and he kept telling me that his bike is faster than mines and his bike has more power and he would pull off the line faster then me. So I say let's take it to the track. But, I don't know much about dirt bikes I haven't riden one and I don't know anyone but this guy who has one. So is it true is a street legal 125 dirt bike faster then a zx 6r. I know it's all about the rider and I'm a pretty fair rider but with this dirtbike being so light and powerful (as he claims) I hope it doesn't eat my little Kawi for breakfast plus I have 100 bucks on the line so can anybody give me any advice
 

·
Registered
Joined
·
716 Posts
"being so light and powerful"

Dude, that describes your bike!! Unless he has done some engine work you should kill him in the 1/8 and 1/4 mile.

It really is all about the rider though. If you sit there and spin the tires at the launch you're not going anywhere
 

·
Registered
Joined
·
1,360 Posts
He might be able to keep up for a second or two, after that its over. Keep in mind your bike will likely go faster in first gear, than his bike will in 6th. Dirt bikes have close-ratio gearing, where as realtively speaking your bike is geared much taller.
 

·
Registered
Joined
·
170 Posts
is his 125 a 4 stroke if so he doesnt have a chance, i raced my friends 250 enduro i wheelied off the line let of the gas to bring it back down and still smoked him with no problem. with my 82 kz550
 

·
Tatters in the Tree House
Joined
·
4,796 Posts
The 125 doesn't have a chance in hell unless you stall it off the line and even then you should be able to catch him and pass him. By the time you go to shift into 3rd he will be staring at your ass end, probably even before then.
 

·
Insomniac
Joined
·
891 Posts
no, he shouldnt stand a chance. i rode a cr125 for quite some time and top speed was only like 70 or so mph. being very generious lets say 100mph. 600ss's should trap about 120mph+ in the 1/4. so, given that you can ride halfway decent, you should beat him by a rather nice margin.
 

·
Registered
Joined
·
8,623 Posts
I've got many, many, many hours on a 125 dirtbike (yz, cr, kx, rm - you name it). No way in hell will it keep up with any 600 ss (well, I guess I should add that this is contingent on you being able to launch your bike)

Yes, they are quick, but nothing like your bike. It's all in the gearing.

1st gear is only good to about 20 mph because of the close ratio. What's yours go to in 1st? 50? 60? He'll have to have shifted 4-5 times by then.

First of all, the 125 will spin like crazy in 1st because of the knobby tire (I've raced mine on the street before :D ) & it will top out under 70 mph. He'll be in 5th gear & won't even be able to see you anymore you'll be so far ahead and you will only be in 2nd.
 

·
Moderator,
Joined
·
16,949 Posts
Krabill said:
Yeah, somewhere between 65 - 70.

Actually, a 500 is only about 85 with stock gearing.
Really? All years? I only ask because an old high school friend had one and actually beat an Amtrak train once that was routinely at about 100mph at this one spot. Guess the trains didn't travel that fast then.
 

·
Heavy Administrator,
Joined
·
527 Posts
He should easily take you for the first 10 ft... assuming hes good, and your average...

After that, bye bye.

To place the safe bet, tell him quarter mile... eigth miles are for pussies... and see what he says....
 

·
Registered
Joined
·
8,623 Posts
Ian said:
Really? All years? I only ask because an old high school friend had one and actually beat an Amtrak train once that was routinely at about 100mph at this one spot. Guess the trains didn't travel that fast then.
Yeah, all years. Again, it's the gearing. You can get them up to 90-95 with sprocket changes, but the fastest one I've ever seen could only hit 105, and that was with a modified gearbox and sprockets together, but stock they will only go about 85. Even that's too fast for backwoods riding, though ;)
 

·
Registered
Joined
·
2,593 Posts
Make it even...start with your bike off and on the side stand.... :D

My buddy has a CR 125..I was really suprised at how UNDERPOWERED they are...they don't "hit" no where near as hard as some 80's we rode growing up. :eek

Really they are designed to have the chit rung out of them......once they are tapped out they have alittle speed to them, but nothing like a 600SS.


B.
 

·
Registered
Joined
·
9,990 Posts
Up to whatever the dirtbikes top speed is, it'll be a race. So if you want to win, make sure you pick a longer distance, like a qtr mile.

But, if you take gearing into account and limit the race to the top speed of say my 300KTM (~70) at 220# about 50-55 rwhp, that should be GSXR-1K power to weight ratio range.
 

·
Registered
Joined
·
1,419 Posts
Of course, you realize if he beats you for one or two feet, he will still be claiming victory and saying that the rest doesn't count. I had a guy in a 4wd 4cyl toyota that wanted to race my old 77 camaro (built 350). He said that it would smoke me from 0 to 10mph in 4wheel low first gear only, my response was: who in the hell cares about going 10mph? Besides, I could smoke the tires up to about 50mph. That guy wouldn't leave me alone for about a year.
 

·
Registered
Joined
·
8,623 Posts
Rsv1000R said:
Up to whatever the dirtbikes top speed is, it'll be a race. So if you want to win, make sure you pick a longer distance, like a qtr mile.

But, if you take gearing into account and limit the race to the top speed of say my 300KTM (~70) at 220# about 50-55 rwhp, that should be GSXR-1K power to weight ratio range.
No . . . it won't be a race. It will be a killing (by the 600ss).

It will crush the poor dirtbiker's idea that his bike is (was?) fast. He'll be wondering if it's actually running right.

And no . . . your Katoom will not even keep up with a 600ss let alone a 1k. It will loose just as quickly as the 125 will. It's all in the gearing. You have to hold it wide open & shift 4 times with a dirt bike to get to 70. On a ss, all you have to do is twist the throttle . . . bye bye dirtbike.

All this talk is just rambling . . . go race the kid & let us know what you find out.
 

·
Registered
Joined
·
9,990 Posts
Krabill said:
It will crush the poor dirtbiker's idea that his bike is (was?) fast. He'll be wondering if it's actually running right.
Have you ridden a late model mx'er? While we disagree about the physics of power to weight ratios and gearing, a 2-stroke mx bike is fast, well everyone I've ridden anyways.

Like Gurney's Alligator, if your race was say for 60' times, I don't think a stock 600SS would stand a chance.
 

·
Registered
Joined
·
8,623 Posts
Rsv1000R said:
Have you ridden a late model mx'er? While we disagree about the physics of power to weight ratios and gearing, a 2-stroke mx bike is fast, well everyone I've ridden anyways.

Like Gurney's Alligator, if your race was say for 60' times, I don't think a stock 600SS would stand a chance.
Yes, I have & like I said . . all this talking doesn't mean anything. Line 'em up :D
 

·
Registered
Joined
·
716 Posts
Krabill said:
All this talk is just rambling . . . go race the kid & let us know what you find out.
Ditto

Take his money
 

·
Registered
Joined
·
24,114 Posts
Discussion Starter #20
Thanks guys for the advice. I'm just going to race him and see what happens. Probably the thing has engine work or some bigger engine smashed in the inside of it I don't know but if I loss I'll get the money back my friend got interested and he's got a race that same day with a busa he's got a 12r drag bike and 250 aprilla race bike and slue of other bikes (11 if I counted right) he said if I lose he'll take his money with the aprilla right back from him so my money is safe. Probably we will both beat him and both make a killin
 
1 - 20 of 22 Posts
Top