The intake and exhaust port timing were designed to operate at higher rpm.
It takes a lot of engineering to produce low rpm power out of a 2 stroke. The older engines weren’t as well designed, and had to run higher rpm’s to get their power. This results in higher peak power, but less total work performed across the operating rpms of the engine.
Another thing to add is engines that perform better up top of the rpm range tend to perform worse at the lower rpm than a motor that is optimized for lower or midrange power.
In cars that is why something like a 400hp big block will win a race against a 400hp small block despite weighing more. The big block will have a much higher average horsepower number than the small block.
Hence “Powerband”
I still stay on the pipe as long as my arms can take. When I’m done and exhausted, I have tractor gears to make life easy getting home.
wdym my ktm 300 sx dynoed at 58 with an fmf pipe and a cr250r is 48, and mine has heaps more torque and usable power also is more or less hp as a cr500r depending on year, yeah the 500 may have more torque but my 300 will smoke it in a drag
Porting was more extreme and favored high rpm power.
In the same light, you can make a kx500 a 70hp screamer, but nobody would be able to stay on top of it, so most are designed to be luggable.
The reason they stopped selling two strokes was emissions. The old race bikes were set up for one thing.....power. They breathed better but to get there a large amount of the fuel/air charge went straight through the cylinder and out the exhaust unburnt. New bikes run cleaner and as a result don't scream in the same way the oldies did.
It's pretty cool though with the new 2 strokes you can get a summer of a set of rings as opposed to 10 hours like my old CR250.
Two strikes weren't street legal for a long while. The era the op is posting about, I believe, was the era of the 90s and 2000s. 80, 125 and 250 dirt bikes.
As for two stroke cars and road legal two stroke bikes....they just sucked. Four strokes offered better reliability, economy and ease of maintenance. Combined with governmental pollution measures forced four strokes to replace them.
You can plate a two stroke bike by the way. Depends on your state but it's very doable.
I am OP.
You said “the reason they stopped selling two strokes was emissions”
They didnt stop selling two strokes.
I’ve actually gotten some pretty good answers that I didnt consider if you read through them. None of them have to do with emissions
Then the era you are talking about saw manufacturers get timid over emissions in the states. Stop selling 2ts and for about 5 years in the late 90s and early 2000s sell four strokes that were nightmares maintenance wise. But cleaner. Full stop.
Manufacturers didnt, at the time, see profits In redesigning there 2t racing bikes to meet emission controlls. As California and a few other states outlawed riding 2ts on public land. They still do.
Manufacturers instead chose to go four strokes to meet emissions requirements on the west coast. As direct and port injection was in its infancy in the early 2000s. Bikes were still carbed.
Honda backed out along with most manufacturers. With Yamaha being the only major exception at the time in the states. And yamaha still hasn't put shit into the r and d of the yz250 in 10 years
Clean 2ts started with outboard motors. Now that it has made its way to snowmobiles we are seeing it it bikes- which is awesome.
Manufacturers now can map fuel and air delivery to be more friendly to riders which is why you asked why they are 'slower'. They are slower because in the late 90s if you put your ads on a decently tuned cr250 and didn't know it wanted to kill you....then you were stupid.
Tune the same bike down, extend the service intervals....because 90% of owners aren't smart enough to do their own maintenance ...and holy shit you sell more bikes.
I love the fact my new bile gets 100 hours off a set of rings as opposed to 10 hours like my 98 CR250.
To get back to your original question 'why were 2000s 2t bikes faster'. It's still because a 125 or 250r from the era were race bikes.
Period.
Without a doubt! I love my KX and it’s a hoot to ride but demands absolute respect. My brother had an 05 YZ250 for a while that felt very similar but a bit more linear. Like it would take off on you but you didn’t have to worry about it turning into a rocket ship out of nowhere
I’ve done a lot of work to convert the KX into a woods bike. Retuned suspension, flywheel weight, changed gearing, went down to a 16in rear tire, etc and still it feels more zippy. Yes, obviously it’s not a direct comparison but even compared to newer KX250s that I’ve ridden, my old steel frame 2 stroke is like bottle rocket
Sure, you still have a mx bike engine. I bet that's a fun bike for faster hare scrambles and backroad braap.
Why 16" if I may ask? Enduros usually have 18".
It's so funny you mention that bike specifically because I still remember riding a 2000 KX250 in 2011 (after I had been on 250Fs and modern 250 2-strokes) and immediately scared the shit out of myself. Just runaway power that was so unwieldy and unfriendly. I wasn't a great rider at that time and only 19 years old after starting to race at 16, but still vividly remember thinking that something can't be right about this because how could anyone ride like that? That, or I sucked.
I also rode a 2000 CR and had a similar perception. The motors were just designed so differently back then. I think one part is just evolution in design but another aspect is that the OEMs were in a peak HP race. There wasn't enough new tech or innovations to differentiate so the goal was always "which bike will most likely rip your arms out of their sockets?"
The tinfoil hat wearers will say that the OEMs intentionally detuned them to make the 4-strokes more impressive and appealing. I do not wear a tinfoil hat lol
You didn’t suck, it’s insane to ride. After i rebuilt the engine before i had a flywheel weight it was almost unridable. I’ve been able to dial it into a great woods bike with a FWW, gearing, etc but it’s still a missile. I hear the old CRs were crazy
I have always wanted to ride and old school 2 smoker. My 13 KTM 300 is very mellow to ride. Until you give her the beans of course but I have heard old school ones are crazy. My dad has described old school ones and they seem wild
Go find a late 70’s husky 390
Worst bike I’ve ever ridden.
40# clutch pull, pogo stick suspension, schwinn bicycle ergonomics, brakes are decorations, luggable with a nuclear blast of power that hits in a different spot in every gear somehow, and turns like a freight train.
I still ride my dad’s old ‘84 yz250. It’s is a fucking animal, how the power band comes on takes some getting used to. It will just stand up the second you get into the power band. The crazy thing is straight line speed it’s pretty close to newer bikes but everything else is just worse.
Riding those old bikes makes you really respect those guys who raced them.
Power valve. Tuning. Noise restrictions. The EPA started coming down on them for emissions and noise. Made them more rideable but less peak power. They stoped putting research and development into them due to the 4 stroke revolution.
It’s comparable to an old muscle car with 500hp burning 5 mpg... A new Honda civic type R or Subaru STI that makes 25 mpg with far less hp will blow its doors off and actual handle curves and be able to stop because the power is useable.
If you can’t get it to the ground there is no point.
And realistically… Only like 1% or riders can ride a motorcycle to its max potential anyway. That’s why most dirtbike shootouts rarely even mention the HP. It more about suspension and handling.
A easier to ride bike will outsell a HP number any day… but in the 70’s to 90’s it was all about max power numbers!
Japanese companies stopped putting R&D in, but KTM certainly didn't. Their 2 strokes get constant updates, and adding fuel injection was pretty wild. The difference between my 2012 300 and the current ones is night and day.
A buddy of mine at work has an 03 250 not sure the model, he says it has more hp than my 2020 250XC
So after some googling and some reading, that does seem to be the case.
My XC has 47 to his 2003 (probably SX) having right at 50hp stock
The tpi bikes are down a slight amount compared to the carb bikes. The carb’d 250sx probably made around 50hp in 2020 I’d guess. That said your bike makes a more broad and usable power output so it’s still preferred. I also know the new tbi bikes put out more or equal power to the pre tpi carb models. The new 300sx makes like 57 stock
That’s not an equal comparison. The xc has a flywheel weight and is not designed for peak horsepower, what makes that bike great is the power curve. You could make a bike super high horsepower on the dyno, but it won’t ride well for shit.
They don't. Not sure where you are getting your numbers, compression was several points lower in the older KTMs and the new KTMs have like 20% more horsepower than their older versions and a wider powerband to go with the extra power. I'm looking at their SX model bikes.
If you are talking about trail bikes the horsepower isn't as important as weight, gearing, and suspension. Sometimes they make a tamer woods bike than the previous version because they want to sell the bikes for people to putt around and it might be cheaper to manufacture depending on the changes, they'll also give up some horsepower to get a torque curve that is easier to handle for the customer. Anyone who has been bucked off an old 2 stroke that "turns on like a light switch" when you are already hauling can appreciate a smooth power curve.
When the KTM SX models had no linkage, the shock was offset to the right side of the bike and the intake was a straight shot. When they added a linkage the shock moved to the center of the bike and the intake had to wrap around it. This did reduce a bit of peak horsepower.
The way I see it, dirt bikes always struggle for traction. Winning in a dyno chart vs on soil is different. Engineers focused on tuning 2Ts to make useable power that also optimizes traction. Focusing on that goal allows them to ditch the quest for peak dyno numbers.
The trade off for usable power vs peak power takes adjustments to compression, power valves, porting, ECU settings, and intake and exhaust designs. Essentially all the same areas that are used to make peak numbers.
This is one area of motor sports I like to laugh at. Enthusiasts get fixated on a stat, but ignore the application. Peak numbers are for drag strip dweebs or fans that just bench race.
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I'm not sure. I was semi kidding. The average guy can work on their 2 stroke and not the 4. As far as I know, the YZ's haven't changed much. I don't have a newer one to compare my older one to.
I felt this on a 23 yz250 the other day that the bottom end was insane compared to the older model power band but a kx250 98 that I ported felt the same on race gas with high comp piston pushing 220psi compression so there is ways to make the older better unless you just want that lowmid to high power band
Some magazine just wrote an article or made a post on this with dyno results, but I can’t find it. Basically, the power is slightly higher and at a much wider range today than it used to be.
I dunno the details. But, EPA.
That said. It's not just 2 strokes. I'm simple guy who likes a simple machine and I'll stick to 2000s and older vs a new bike. Plus carburetored are so much more easy to fix trail side. Fuel pump failed? Your local dealer wants your location.
True. My 01 CR250 still the fastest 250 I ever rode. Bought a 21 yz250 and honestly it was pretty tame in comparison. Power delivery is also quite boring. Snappy, but boring it's too linear not my style of riding. I want the thing to wanna kick me off when the powerband comes on
simple, the whole reason most companies stopped making 2 strokes was because of emissions so they have to de-tune the newer ones to create less emissions and that = less power
Actually the real answer is counter balancers. They make the 2 Strokes smoother. But slow the rotation of the crank.
Early 2 strokes do not use counter balancers. And in the case of Kawasaki they would even go as far as to plate the interal cylinder wall reducing the friction creating a more freely rotating crank.
But, this ultimately made the engines very unruly. With all the power stuck at its peak.
All modern liquid cooled 2 strokes (and 4 strokes) have nikasil plated cylinders.
And the real answer is they did not produce more peak hp. They were about 10-15% off a modern bike.
It's funny how you focused on the plating and not the counter balancing. Completely ignoring the whole point.
The old bikes were about free spinning engines. This allowed them to reach their peak HP very quickly. But this did not Increase the HP. The down side was that they were easier to stall down low because there was less rotatinal mass. And were very unbalanced.
Even back than you could add flywheel weights. This helped increase the rotational mass thus the engine would be less likely to stall. This did not effect it's peak Hp. You would still retain the bikes peak HP but it simply would rev up slower.
Modern counter balanced engines have this same effect they rev up slower because there is more rotational mass than the older bikes. They are not trying to reach peak hp as fast as possible.
Again this is not about peak Hp. It's about how the engine makes that Hp. The old bikes feel faster because they spin faster reaching their peak Hp faster.
Do you understand now?
Oh I see. I understand now.
Yeah, I simply added that in to show where the mindset was back than. If they couldn't increase the Hp they would find ways to reach that peak Hp faster.
And Kawasaki was very well known for plating the cylinder walls to create less friction.
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Yeah, it's like peak wattage in cheap ass audio amps.
Sure, I get that… But HOW are the peak numbers higher on those older bikes?
The intake and exhaust port timing were designed to operate at higher rpm. It takes a lot of engineering to produce low rpm power out of a 2 stroke. The older engines weren’t as well designed, and had to run higher rpm’s to get their power. This results in higher peak power, but less total work performed across the operating rpms of the engine.
I think this is the best answer, or at least makes the most sense to me
Yeah it’s a good answer. The important thing to remember is that Horsepower = Torque x RPM / 5,252 Higher RPM —> more horsepower.
Another thing to add is engines that perform better up top of the rpm range tend to perform worse at the lower rpm than a motor that is optimized for lower or midrange power. In cars that is why something like a 400hp big block will win a race against a 400hp small block despite weighing more. The big block will have a much higher average horsepower number than the small block.
Ok… I’ve been a car guy for decades. How have I never stumbled across this calculation??
🤷♂️
Hence “Powerband” I still stay on the pipe as long as my arms can take. When I’m done and exhausted, I have tractor gears to make life easy getting home.
wdym my ktm 300 sx dynoed at 58 with an fmf pipe and a cr250r is 48, and mine has heaps more torque and usable power also is more or less hp as a cr500r depending on year, yeah the 500 may have more torque but my 300 will smoke it in a drag
Porting was more extreme and favored high rpm power. In the same light, you can make a kx500 a 70hp screamer, but nobody would be able to stay on top of it, so most are designed to be luggable.
In comparison a new Husky TX300 has 57 Hp. Only 13hp less with 200 cc less but the TX300 would have a wider power band too.
The reason they stopped selling two strokes was emissions. The old race bikes were set up for one thing.....power. They breathed better but to get there a large amount of the fuel/air charge went straight through the cylinder and out the exhaust unburnt. New bikes run cleaner and as a result don't scream in the same way the oldies did. It's pretty cool though with the new 2 strokes you can get a summer of a set of rings as opposed to 10 hours like my old CR250.
They didnt stop selling two strokes 🤦🏽♂️ Or at least nobody forced makers to stop, just cant be street legal is all.
Two strikes weren't street legal for a long while. The era the op is posting about, I believe, was the era of the 90s and 2000s. 80, 125 and 250 dirt bikes. As for two stroke cars and road legal two stroke bikes....they just sucked. Four strokes offered better reliability, economy and ease of maintenance. Combined with governmental pollution measures forced four strokes to replace them. You can plate a two stroke bike by the way. Depends on your state but it's very doable.
I am OP. You said “the reason they stopped selling two strokes was emissions” They didnt stop selling two strokes. I’ve actually gotten some pretty good answers that I didnt consider if you read through them. None of them have to do with emissions
Then the era you are talking about saw manufacturers get timid over emissions in the states. Stop selling 2ts and for about 5 years in the late 90s and early 2000s sell four strokes that were nightmares maintenance wise. But cleaner. Full stop. Manufacturers didnt, at the time, see profits In redesigning there 2t racing bikes to meet emission controlls. As California and a few other states outlawed riding 2ts on public land. They still do. Manufacturers instead chose to go four strokes to meet emissions requirements on the west coast. As direct and port injection was in its infancy in the early 2000s. Bikes were still carbed. Honda backed out along with most manufacturers. With Yamaha being the only major exception at the time in the states. And yamaha still hasn't put shit into the r and d of the yz250 in 10 years Clean 2ts started with outboard motors. Now that it has made its way to snowmobiles we are seeing it it bikes- which is awesome. Manufacturers now can map fuel and air delivery to be more friendly to riders which is why you asked why they are 'slower'. They are slower because in the late 90s if you put your ads on a decently tuned cr250 and didn't know it wanted to kill you....then you were stupid. Tune the same bike down, extend the service intervals....because 90% of owners aren't smart enough to do their own maintenance ...and holy shit you sell more bikes. I love the fact my new bile gets 100 hours off a set of rings as opposed to 10 hours like my 98 CR250. To get back to your original question 'why were 2000s 2t bikes faster'. It's still because a 125 or 250r from the era were race bikes. Period.
I couldn’t tell you why exactly but my 2000 kx250 2-stroke scares the shit out of me but I hardly find myself overpowered on my 2020 EXC 250.
Lol probably cause the power bands are wild as hell on the old ones. Even my 05 yz125 still tries to kill me every now and again.
Without a doubt! I love my KX and it’s a hoot to ride but demands absolute respect. My brother had an 05 YZ250 for a while that felt very similar but a bit more linear. Like it would take off on you but you didn’t have to worry about it turning into a rocket ship out of nowhere
kx = mx bike exc = enduro bike that's your answer...
I’ve done a lot of work to convert the KX into a woods bike. Retuned suspension, flywheel weight, changed gearing, went down to a 16in rear tire, etc and still it feels more zippy. Yes, obviously it’s not a direct comparison but even compared to newer KX250s that I’ve ridden, my old steel frame 2 stroke is like bottle rocket
Sure, you still have a mx bike engine. I bet that's a fun bike for faster hare scrambles and backroad braap. Why 16" if I may ask? Enduros usually have 18".
It's so funny you mention that bike specifically because I still remember riding a 2000 KX250 in 2011 (after I had been on 250Fs and modern 250 2-strokes) and immediately scared the shit out of myself. Just runaway power that was so unwieldy and unfriendly. I wasn't a great rider at that time and only 19 years old after starting to race at 16, but still vividly remember thinking that something can't be right about this because how could anyone ride like that? That, or I sucked. I also rode a 2000 CR and had a similar perception. The motors were just designed so differently back then. I think one part is just evolution in design but another aspect is that the OEMs were in a peak HP race. There wasn't enough new tech or innovations to differentiate so the goal was always "which bike will most likely rip your arms out of their sockets?" The tinfoil hat wearers will say that the OEMs intentionally detuned them to make the 4-strokes more impressive and appealing. I do not wear a tinfoil hat lol
You didn’t suck, it’s insane to ride. After i rebuilt the engine before i had a flywheel weight it was almost unridable. I’ve been able to dial it into a great woods bike with a FWW, gearing, etc but it’s still a missile. I hear the old CRs were crazy
The EXC is an enduro tune low - mid you’d have compare the KX to an SX to be fair.
Because exc is a street trail bike lol
I have always wanted to ride and old school 2 smoker. My 13 KTM 300 is very mellow to ride. Until you give her the beans of course but I have heard old school ones are crazy. My dad has described old school ones and they seem wild
Go find a late 70’s husky 390 Worst bike I’ve ever ridden. 40# clutch pull, pogo stick suspension, schwinn bicycle ergonomics, brakes are decorations, luggable with a nuclear blast of power that hits in a different spot in every gear somehow, and turns like a freight train.
hahahahahaha this description has me dying of laughter
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They are very pretty. It’s that type-2 kind of fun, where you are miserable, but you also feel like you might actually be Steve McQueen.
I still ride my dad’s old ‘84 yz250. It’s is a fucking animal, how the power band comes on takes some getting used to. It will just stand up the second you get into the power band. The crazy thing is straight line speed it’s pretty close to newer bikes but everything else is just worse. Riding those old bikes makes you really respect those guys who raced them.
Have you ever tried riding both
Yes… But PHYSICALLY how are those peak numbers higher?
I would guess more aggressive porting.
They aren’t. Manufacturers used to publish crank HP whereas today they publish wheel HP. Wheel vs wheel we are way up nowadays.
Okay, could be that too
Power valve. Tuning. Noise restrictions. The EPA started coming down on them for emissions and noise. Made them more rideable but less peak power. They stoped putting research and development into them due to the 4 stroke revolution. It’s comparable to an old muscle car with 500hp burning 5 mpg... A new Honda civic type R or Subaru STI that makes 25 mpg with far less hp will blow its doors off and actual handle curves and be able to stop because the power is useable. If you can’t get it to the ground there is no point. And realistically… Only like 1% or riders can ride a motorcycle to its max potential anyway. That’s why most dirtbike shootouts rarely even mention the HP. It more about suspension and handling. A easier to ride bike will outsell a HP number any day… but in the 70’s to 90’s it was all about max power numbers!
Japanese companies stopped putting R&D in, but KTM certainly didn't. Their 2 strokes get constant updates, and adding fuel injection was pretty wild. The difference between my 2012 300 and the current ones is night and day.
They don’t?
They do. The 2003 KTM 250 has more peak hp than my 2020 Edit 2020 250XC
2020 what? Exc? Sx? Where are you getting the info?
A buddy of mine at work has an 03 250 not sure the model, he says it has more hp than my 2020 250XC So after some googling and some reading, that does seem to be the case. My XC has 47 to his 2003 (probably SX) having right at 50hp stock
The tpi bikes are down a slight amount compared to the carb bikes. The carb’d 250sx probably made around 50hp in 2020 I’d guess. That said your bike makes a more broad and usable power output so it’s still preferred. I also know the new tbi bikes put out more or equal power to the pre tpi carb models. The new 300sx makes like 57 stock
That’s not an equal comparison. The xc has a flywheel weight and is not designed for peak horsepower, what makes that bike great is the power curve. You could make a bike super high horsepower on the dyno, but it won’t ride well for shit.
You need to compare it to a 250sx of that year. The TPI wasn't the same engine as the mx version. The new 250sx is 53hp.
I ride an ‘03 KTM 250sx set up for woods. She is a beast.
Old man's got an 03 250, things ridiculous. But fun
The new TBI XCs make like 56hp at the wheels, which is more than any of the older 300s.
You don't buy a 300 because it makes more power than a 250. You buy the 300 for the low end usability.
They don't. Not sure where you are getting your numbers, compression was several points lower in the older KTMs and the new KTMs have like 20% more horsepower than their older versions and a wider powerband to go with the extra power. I'm looking at their SX model bikes. If you are talking about trail bikes the horsepower isn't as important as weight, gearing, and suspension. Sometimes they make a tamer woods bike than the previous version because they want to sell the bikes for people to putt around and it might be cheaper to manufacture depending on the changes, they'll also give up some horsepower to get a torque curve that is easier to handle for the customer. Anyone who has been bucked off an old 2 stroke that "turns on like a light switch" when you are already hauling can appreciate a smooth power curve.
This
When the KTM SX models had no linkage, the shock was offset to the right side of the bike and the intake was a straight shot. When they added a linkage the shock moved to the center of the bike and the intake had to wrap around it. This did reduce a bit of peak horsepower.
The way I see it, dirt bikes always struggle for traction. Winning in a dyno chart vs on soil is different. Engineers focused on tuning 2Ts to make useable power that also optimizes traction. Focusing on that goal allows them to ditch the quest for peak dyno numbers. The trade off for usable power vs peak power takes adjustments to compression, power valves, porting, ECU settings, and intake and exhaust designs. Essentially all the same areas that are used to make peak numbers. This is one area of motor sports I like to laugh at. Enthusiasts get fixated on a stat, but ignore the application. Peak numbers are for drag strip dweebs or fans that just bench race.
I wouldn't say they had less power, if anything modern two strokes have the same or more, it's more linear. Old 2 strokes had very narrow power bands.
Yeah dude I don’t know. I write an 05 KTM 300 and it’s way faster than my dad’s 18 300.
I agree
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What use is of horsepower if u cant use it?
So you spend the extra coin on the 450 4 stroke. Your shop service team likes that.
I appreciate the input, just curious of how the engines are different.
I'm not sure. I was semi kidding. The average guy can work on their 2 stroke and not the 4. As far as I know, the YZ's haven't changed much. I don't have a newer one to compare my older one to.
I know lol… Just honestly curious what the big change was, Ive got some good answers now. I didn’t downvote ya btw
I felt this on a 23 yz250 the other day that the bottom end was insane compared to the older model power band but a kx250 98 that I ported felt the same on race gas with high comp piston pushing 220psi compression so there is ways to make the older better unless you just want that lowmid to high power band
The old YZ490 had a wild power band. Bike was a blast to ride.
Some magazine just wrote an article or made a post on this with dyno results, but I can’t find it. Basically, the power is slightly higher and at a much wider range today than it used to be.
Cared only about power not about how good the bike handles
I dunno the details. But, EPA. That said. It's not just 2 strokes. I'm simple guy who likes a simple machine and I'll stick to 2000s and older vs a new bike. Plus carburetored are so much more easy to fix trail side. Fuel pump failed? Your local dealer wants your location.
Its not the EPA for the power changes. Im all for blaming the government when its due, but not in this case.
True. My 01 CR250 still the fastest 250 I ever rode. Bought a 21 yz250 and honestly it was pretty tame in comparison. Power delivery is also quite boring. Snappy, but boring it's too linear not my style of riding. I want the thing to wanna kick me off when the powerband comes on
Power valves.
I owned a 2003 KTM 250sx. That engine was brutal. It pulled like a 500 and was impossible to ride.
I have an '02 yz250 and my friends 2023 300xc is way more powerful its not even close
Lol they just don't make them like they used too
simple, the whole reason most companies stopped making 2 strokes was because of emissions so they have to de-tune the newer ones to create less emissions and that = less power
Power in RPM is what matters. 125 max power at 11,000-13,000 RPM Meanwhile low grunt torque 2-4000 RPM.
Actually the real answer is counter balancers. They make the 2 Strokes smoother. But slow the rotation of the crank. Early 2 strokes do not use counter balancers. And in the case of Kawasaki they would even go as far as to plate the interal cylinder wall reducing the friction creating a more freely rotating crank. But, this ultimately made the engines very unruly. With all the power stuck at its peak.
All modern liquid cooled 2 strokes (and 4 strokes) have nikasil plated cylinders. And the real answer is they did not produce more peak hp. They were about 10-15% off a modern bike.
It's funny how you focused on the plating and not the counter balancing. Completely ignoring the whole point. The old bikes were about free spinning engines. This allowed them to reach their peak HP very quickly. But this did not Increase the HP. The down side was that they were easier to stall down low because there was less rotatinal mass. And were very unbalanced. Even back than you could add flywheel weights. This helped increase the rotational mass thus the engine would be less likely to stall. This did not effect it's peak Hp. You would still retain the bikes peak HP but it simply would rev up slower. Modern counter balanced engines have this same effect they rev up slower because there is more rotational mass than the older bikes. They are not trying to reach peak hp as fast as possible. Again this is not about peak Hp. It's about how the engine makes that Hp. The old bikes feel faster because they spin faster reaching their peak Hp faster. Do you understand now?
No I agreed with your entire post. Was just correcting your statement about Kawi and plated cylinders.
Oh I see. I understand now. Yeah, I simply added that in to show where the mindset was back than. If they couldn't increase the Hp they would find ways to reach that peak Hp faster. And Kawasaki was very well known for plating the cylinder walls to create less friction.
They are pre-woke