"This is the best 250cc two-stroke bike ever made".

miedosoracing1 11/8/2011 11:05am
11/8/2011 11:05am
nickm wrote:
Here's a twist on this topic, the best 250 every made was a 500cc....IMO small displacement ruined the two stroke..who the hell wants a 125 or...
Here's a twist on this topic, the best 250 every made was a 500cc....IMO small displacement ruined the two stroke..who the hell wants a 125 or 250 strung out so badly that it makes all of its horsepower within a 1K rpm band, they are tough to ride and tough to get power to the ground.

Get a 500cc 2 stoke making "only" 55-60hp, avoid any power valve (like CR500s didn't have) and you'll get the same broad, smooth, tractable power you get out of a 4 sdtroke 450.
CamP wrote:
That's sounds great in theory, but the reality is that the 500cc two stroke has a huge crankshaft that creates a lot of inertia. It's a...
That's sounds great in theory, but the reality is that the 500cc two stroke has a huge crankshaft that creates a lot of inertia. It's a big gyroscope that doesn't want to change direction.
Agreed, I loved my 500, but for most people it was too much, like I've been saying a 350SX from KTM with electric start and balanced motor would beat all..
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nickm 11/8/2011 12:23pm
11/8/2011 12:23pm
nickm wrote:
Here's a twist on this topic, the best 250 every made was a 500cc....IMO small displacement ruined the two stroke..who the hell wants a 125 or...
Here's a twist on this topic, the best 250 every made was a 500cc....IMO small displacement ruined the two stroke..who the hell wants a 125 or 250 strung out so badly that it makes all of its horsepower within a 1K rpm band, they are tough to ride and tough to get power to the ground.

Get a 500cc 2 stoke making "only" 55-60hp, avoid any power valve (like CR500s didn't have) and you'll get the same broad, smooth, tractable power you get out of a 4 sdtroke 450.
CamP wrote:
That's sounds great in theory, but the reality is that the 500cc two stroke has a huge crankshaft that creates a lot of inertia. It's a...
That's sounds great in theory, but the reality is that the 500cc two stroke has a huge crankshaft that creates a lot of inertia. It's a big gyroscope that doesn't want to change direction.
miedosoracing1 wrote:
Agreed, I loved my 500, but for most people it was too much, like I've been saying a 350SX from KTM with electric start and balanced...
Agreed, I loved my 500, but for most people it was too much, like I've been saying a 350SX from KTM with electric start and balanced motor would beat all..
There's some soultion to be had there...I really dislike strung out 2 strokes (like most of the 125s and some 250s were) and every time I get on a 300 2 stroke offroader, I absolutely LOVE it. broad, smooth tractable power everywhere. You can ride the things like a 4T, no need to abuse the crap out of a clutch in an attempt to keep in in a razor thin power range...and unlike a 4 stroke throttle response is INSTANT.

Yes 500s have large cranks, but the 450s have a large crank and a rotating valetrain, given equal chassis, its not like a 500 2T will turn worse than a 450 4T.

Maybe a 350 2T is the best of both worlds...
burn1986
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burn1986 11/8/2011 12:27pm
11/8/2011 12:27pm
ATKpilot99 wrote:
Probably. They've also done the YZ 250 vs yz 250f comparison. It might be interesting to see a shootout, but the basic conclusion they came to...
Probably. They've also done the YZ 250 vs yz 250f comparison. It might be interesting to see a shootout, but the basic conclusion they came to in these comparisons was the 2 stroke had certain advantages and so did the 250f. In the end riders were able to turn similar lap times on average on both machines.
Yeah, I've seen those. I'm sure there is an agreement with the OEMs that they won't put them in a shootout against another brand, like a KTM 250 / 150SX against any one of the Big 4.
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rallendude 11/8/2011 12:29pm
11/8/2011 12:29pm
I was thinking the same. The best 250 is a 500. But, they do have their limits. I have a Service Honda and it's a blast to ride. But it took me almost a year to get used to it where I used to jump from bike to bike with relative ease. The turning is no big deal. It's in a 250f chassis and turned much better than my 450s have. When you roll the power on in the turns it wants to push but that's because the front isn't on the ground anymore.

The big deal for me is the 500 with no powervalve is like a light switch up where the real power is. It makes great bottom and you can lug it all day but when you get up around the power it really gets almost unpredictable. You really have to get to know the bike to not put yourself in bad situations.

I do like a 300 though.

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CamP 11/8/2011 12:34pm
11/8/2011 12:34pm Edited Date/Time 11/8/2011 12:36pm
CamP wrote:
That's sounds great in theory, but the reality is that the 500cc two stroke has a huge crankshaft that creates a lot of inertia. It's a...
That's sounds great in theory, but the reality is that the 500cc two stroke has a huge crankshaft that creates a lot of inertia. It's a big gyroscope that doesn't want to change direction.
miedosoracing1 wrote:
Agreed, I loved my 500, but for most people it was too much, like I've been saying a 350SX from KTM with electric start and balanced...
Agreed, I loved my 500, but for most people it was too much, like I've been saying a 350SX from KTM with electric start and balanced motor would beat all..
nickm wrote:
There's some soultion to be had there...I really dislike strung out 2 strokes (like most of the 125s and some 250s were) and every time I...
There's some soultion to be had there...I really dislike strung out 2 strokes (like most of the 125s and some 250s were) and every time I get on a 300 2 stroke offroader, I absolutely LOVE it. broad, smooth tractable power everywhere. You can ride the things like a 4T, no need to abuse the crap out of a clutch in an attempt to keep in in a razor thin power range...and unlike a 4 stroke throttle response is INSTANT.

Yes 500s have large cranks, but the 450s have a large crank and a rotating valetrain, given equal chassis, its not like a 500 2T will turn worse than a 450 4T.

Maybe a 350 2T is the best of both worlds...
450 4-strokes have a much smaller crank than a 500 2-stroke. For example, a CRF450 has a 62.1mm stroke and a CR500 has a 79mm stroke. That big 79mm stroke crank generates a lot of inertia and that's why the CR500 will never handle as well as the CRF450.

A 350T is a nice compromise. I loved the 368cc 380SX I use to ride.
burn1986
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burn1986 11/8/2011 12:42pm
11/8/2011 12:42pm
Yep, a 350 2-stroke would be the ultimate weapon outdoors. I'm still convinced that a 250-300 2-stroke would be the best choice indoors against a 450.
miedosoracing1 11/8/2011 12:53pm
11/8/2011 12:53pm Edited Date/Time 11/8/2011 12:54pm
CamP wrote:
450 4-strokes have a much smaller crank than a 500 2-stroke. For example, a CRF450 has a 62.1mm stroke and a CR500 has a 79mm stroke...
450 4-strokes have a much smaller crank than a 500 2-stroke. For example, a CRF450 has a 62.1mm stroke and a CR500 has a 79mm stroke. That big 79mm stroke crank generates a lot of inertia and that's why the CR500 will never handle as well as the CRF450.

A 350T is a nice compromise. I loved the 368cc 380SX I use to ride.
I agreed with you until you said a 500AF wouldn't handle as good as a 450F. I wish I had mine still, to prove to you. Year for year, 2004 CRF450 and My 2004 CR250 framed 500F did circles around that 450F. So comparing a new 500AF in a 2012 CRF250 frame and a 2012 CRF450 would really really surprise you. Power is the problem, handling was not. It actually "feels" lighter than a 2010 CRF450. The last 450F I rode.
burn1986
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burn1986 11/8/2011 1:04pm
11/8/2011 1:04pm
Most of the rumors about the 500AFs not turning is baloney and misinformation. A lot of it IMO is the riders don't understand the inertia of a 500cc 2-stroke, and the feel it has in the turns. There is a little more gyroscopic effect in turns, but still a light bike with light moving parts.
CamP
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CamP 11/8/2011 1:06pm
11/8/2011 1:06pm
Handling is more than just how a bike turns.
miedosoracing1 11/8/2011 1:13pm
11/8/2011 1:13pm Edited Date/Time 11/8/2011 1:25pm
CamP wrote:
Handling is more than just how a bike turns.
I agree. Trust me, the CR500AF handles better than a 450F. Maybe that is why they ran faster lap times on a CR500AF and a KX450AF in comparison shootouts.

http://twostrokemotocross.com/wp-content/uploads/2008/08/service_honda_…
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Suns_PSD 11/8/2011 3:24pm
11/8/2011 3:24pm
rallendude wrote:
I was thinking the same. The best 250 is a 500. But, they do have their limits. I have a Service Honda and it's a blast...
I was thinking the same. The best 250 is a 500. But, they do have their limits. I have a Service Honda and it's a blast to ride. But it took me almost a year to get used to it where I used to jump from bike to bike with relative ease. The turning is no big deal. It's in a 250f chassis and turned much better than my 450s have. When you roll the power on in the turns it wants to push but that's because the front isn't on the ground anymore.

The big deal for me is the 500 with no powervalve is like a light switch up where the real power is. It makes great bottom and you can lug it all day but when you get up around the power it really gets almost unpredictable. You really have to get to know the bike to not put yourself in bad situations.

I do like a 300 though.
You need to get your motor built by someone that knows what he is doing.

I have a friend w/ a homebuilt 500AF . He ported and carbed the motor for a screaming top end and it's amazing. Super smooth and easy to ride from the very bottom to the very top. None of the huge violent hit that 500s are known for.

It also turns like a CR125. It's incredibly nimble.
nickm
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nickm 11/8/2011 3:47pm
11/8/2011 3:47pm
miedosoracing1 wrote:
Agreed, I loved my 500, but for most people it was too much, like I've been saying a 350SX from KTM with electric start and balanced...
Agreed, I loved my 500, but for most people it was too much, like I've been saying a 350SX from KTM with electric start and balanced motor would beat all..
nickm wrote:
There's some soultion to be had there...I really dislike strung out 2 strokes (like most of the 125s and some 250s were) and every time I...
There's some soultion to be had there...I really dislike strung out 2 strokes (like most of the 125s and some 250s were) and every time I get on a 300 2 stroke offroader, I absolutely LOVE it. broad, smooth tractable power everywhere. You can ride the things like a 4T, no need to abuse the crap out of a clutch in an attempt to keep in in a razor thin power range...and unlike a 4 stroke throttle response is INSTANT.

Yes 500s have large cranks, but the 450s have a large crank and a rotating valetrain, given equal chassis, its not like a 500 2T will turn worse than a 450 4T.

Maybe a 350 2T is the best of both worlds...
CamP wrote:
450 4-strokes have a much smaller crank than a 500 2-stroke. For example, a CRF450 has a 62.1mm stroke and a CR500 has a 79mm stroke...
450 4-strokes have a much smaller crank than a 500 2-stroke. For example, a CRF450 has a 62.1mm stroke and a CR500 has a 79mm stroke. That big 79mm stroke crank generates a lot of inertia and that's why the CR500 will never handle as well as the CRF450.

A 350T is a nice compromise. I loved the 368cc 380SX I use to ride.
You're forgetting the valetrain and related parts, that timing chain connecting the bottom to the top end and the rotating cam(s) also generate gyro effect (they are all spinning), and its much higher up on the bike than the CR500 crank. Not to mention you have to lug around an extra 20-30 lbs with the 4 stroke.

I own and ride an '89 CR500 and an '08 CRF450, while the 08 obviously has the superior chassis I can't say it really handles better than the 89...

I agree the old 89 is sometimes unpredictable, especially when you load it up...but I'd just LOVE to ride a modern fuel injected 2 stroke 500 tuned the same way KTM tunes their 300 2 stroke offroad lineup.
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CamP 11/8/2011 4:53pm
11/8/2011 4:53pm
nickm wrote:
You're forgetting the valetrain and related parts, that timing chain connecting the bottom to the top end and the rotating cam(s) also generate gyro effect (they...
You're forgetting the valetrain and related parts, that timing chain connecting the bottom to the top end and the rotating cam(s) also generate gyro effect (they are all spinning), and its much higher up on the bike than the CR500 crank. Not to mention you have to lug around an extra 20-30 lbs with the 4 stroke.

I own and ride an '89 CR500 and an '08 CRF450, while the 08 obviously has the superior chassis I can't say it really handles better than the 89...

I agree the old 89 is sometimes unpredictable, especially when you load it up...but I'd just LOVE to ride a modern fuel injected 2 stroke 500 tuned the same way KTM tunes their 300 2 stroke offroad lineup.
A 1" diameter camshaft places very little centrifugal force on the motorcycle because it's mass and diameter are small. The crankshaft, on the other hand, acts like a gyroscope on the bike because it's mass and diameter are large.
nickm
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nickm 11/9/2011 7:13am
11/9/2011 7:13am
CamP wrote:
A 1" diameter camshaft places very little centrifugal force on the motorcycle because it's mass and diameter are small. The crankshaft, on the other hand, acts...
A 1" diameter camshaft places very little centrifugal force on the motorcycle because it's mass and diameter are small. The crankshaft, on the other hand, acts like a gyroscope on the bike because it's mass and diameter are large.
...in any case I'm sure a niche marketer like KTM is/has experimented with all kinds of displacements and has shown a number of times that they aren't afraid to bring a niche bike to market. I'm sure if there's a buyer for it they will make it.

The point I was trying to make from the start was that small displacement 2 strokes end up with a super narrow power range, larger displacement 2 strokes and those tuned for off road use have nice broad and tractable powerband. it would be nice to have a larger displacement 2 stoke, tuned like an offroad bike so that it makes the peak power everyone seems to want (ie: 55+hp) yet has smooth tractable power. A modern version of this (ie: with direct injection) would also eliminate all the old problems like "loading up" and plug fouling that 2 stokes always had...

Having ridden 2 strokes of all displacements over the past 20 years I still say the best 250 2T is a 500 Smile
burn1986
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burn1986 11/9/2011 7:24am
11/9/2011 7:24am
Suns_PSD wrote:
Here is a link to a thread where I compared a well dialed 500AF to a well dialed CR450F.

http://www.vitalmx.com/forums/Moto-Related,20/Got-to-ride-a-450F-back-t…
Very good report. There is no doubt the 450s are good MX machines, but only because of the constant revisions it has received. If the 500 had received the same updates, then IMO it would be a clearly more efficient and better MX machine. I actually think the 500 would do better with an updated steel frame instead of the aluminum, just my opinion.
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Randy Olson 11/9/2011 12:55pm
11/9/2011 12:55pm
What two stroke most changed the sport at the time it was introduced? OR What two-stroke was so good at the time that it dominated the local races and everyone rushed out to buy one?
burn1986
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burn1986 11/9/2011 12:57pm
11/9/2011 12:57pm
Shoot, any CR125 from 84 to 97. And of course 87 CR250.

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nickm
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nickm 11/9/2011 4:04pm
11/9/2011 4:04pm
burn1986 wrote:
Shoot, any CR125 from 84 to 97. And of course 87 CR250.
I was going to say 86 or 87 CR250
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Skunk 11/14/2011 12:52pm
11/14/2011 12:52pm
Bump
tryston.longardner 7/2/2013 1:39pm
7/2/2013 1:39pm
I would say the 94-98 kx250 had the fastest motor if u have ridden one u would understand
newmann
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newmann 7/2/2013 2:28pm
7/2/2013 2:28pm
Welcome to two years ago everyone! Laughing
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peelout 7/2/2013 2:40pm
7/2/2013 2:40pm
peelout wrote:
my next new skooter will be this exact machine.

thanks for posting the link
well... 2.5 years after that post i bought a 2012 XC250 with a 300SX kit... so i was pretty damn close
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newmann 7/2/2013 2:50pm
7/2/2013 2:50pm
peelout wrote:
my next new skooter will be this exact machine.

thanks for posting the link
peelout wrote:
well... 2.5 years after that post i bought a 2012 XC250 with a 300SX kit... so i was pretty damn close
You predicted the future?? Peely Kreshkin?
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JW381 7/2/2013 3:15pm
7/2/2013 3:15pm
I wanna ride one. I like my CR for sure, handles great. I didn't like my YZ all that much. My CR is an 04 and the YZ was an 09. I'd be interested to feel one of those orange rocket ships.
mynewcr250 7/2/2013 7:56pm
7/2/2013 7:56pm Edited Date/Time 7/2/2013 7:56pm
CamP wrote:
Handling is more than just how a bike turns.
miedosoracing1 wrote:
I agree. Trust me, the CR500AF handles better than a 450F. Maybe that is why they ran faster lap times on a CR500AF and a KX450AF...
I agree. Trust me, the CR500AF handles better than a 450F. Maybe that is why they ran faster lap times on a CR500AF and a KX450AF in comparison shootouts.

http://twostrokemotocross.com/wp-content/uploads/2008/08/service_honda_…
this thread is old as shit, but im glad someone bumped it cause i have not seen this article before
TannerMxer
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TannerMxer 7/2/2013 9:12pm
7/2/2013 9:12pm
I've always been biased for the clean, simple look of this bike.

cobrienmx
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cobrienmx 7/2/2013 11:32pm
7/2/2013 11:32pm
My 2005 RM 250 is a contender. I do drink Monster energy drinks.
motomike894
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motomike894 7/3/2013 4:20am
7/3/2013 4:20am
My banana is pretty hot




YZ125H1
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YZ125H1 7/3/2013 9:00am
7/3/2013 9:00am
Which 250 2T has the narrowest seat? I'd guess Honda or Suzuki? Ive seen the new yz250 the seat looks just as wide as my 96 yz125 :/

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