Hey, I just wanted to ask everyone about a race, there is a kid I know that has a 2003 white LTZ bone stock and my other friend has a 1988 yz250 with a brand new top and bottem end rebuild. He has a lot of stuff on his bike including, wiseco hot rod, sleeved and bored out to a 400, full port and polish, milled head, boyesen reeds, jetted, FMF pipe and silencer. Well the kid I know with the LTZ thinks in a flat drag race he can eat him...hes really cocky cause he said there is no way an 1988 can beat an 2003 no matter what it is. So I was just wondering what you think about them in a flat drag on the road...they are both good riders and my friend on the yz weighs a little more. Thanks a lot let me know asap

 

You're talking 400 2stroke vs. 400 4stroke. That's a no brainer. of course the two stroke will win, even if they were both quads, which is not the case. 2stroke accelerate faster, pure and simple. Besides, top speed on a z is only 67-70mph, top speed on a stock '88 yz 250 is around 90mph. I've seen a stock '86 kx80 do 70mph. The z is fast for four wheels, but is a snail compared to two.


And tell your friend to put a 2003 anything car up against a rebuilt 1988 Shelby Daytona with a few mods.

 

I agree.

 

I’ve never seen any stock dirtbikes do 90, it’s been quite a while since I’ve paid any attention to dirtbikes but it seems like top end on a YZ250 was more like 65. Also, I’ve never heard of a YZ250 being bored out to 400ccs.

The YZ250 will win though regardless. It shouldn’t even be much of a race.

 

Yeah, I don't know much about YZs, but bored and sleeved to a 400 from a 250? With no change in the stroke? That just sounds weird to me. My CR125 tops out around 65, so I think I a YZ 250 would have a little more power to pull it to around 75, but its all in the gearing. My brother had a '97 KX100 that would beat my CR on top end, but it was a 6 speed and was geared lower. I would out accelerate him coming out of every corner though. Nevertheless to get back on topic, the YZ should walk him like a dog.

 

if the bike doesn't flip over during the launch it won't even be close

 

first off a dirtbike wont do 90...second off all the yz250 will smoke the z400 even though i luv the Z...i have one...i hate to say it but dirtbikes are naturally faster than quads. its only the truth and dont try to tell me otherwise