Modern V-4 2 smoke
06-09-2014 | 06:15 PM
#1
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Modern V-4 2 smoke
This is it for me... I'd give up twins, yes I said it. 
ronax-500cc-v-four-two-stroke-trackday-streetbike
ronax-500cc-v-four-two-stroke-trackday-streetbike
06-09-2014 | 07:27 PM
#2
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Yah, I had an Aprilia RS50 2 stroke years ago. It was punched out to a 72cc. I only lived about 10 miles from work and commuted on the back roads. Every ride on it was awesome! Every time I left a stop light it was wide open. Every start was a grand prix start to keep up with traffic. Very fun bike...
James
James
06-09-2014 | 08:15 PM
#6
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There have been 2 stroke V4 race bikes in the past.
e.g: Suzuki RGV500
06-09-2014 | 09:32 PM
#9
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06-09-2014 | 10:40 PM
#10
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True. Fun they are but very impractical and a lot more upkeep. The bottom line is that 4 stroke engines are a much more efficient power plant. Obviously 2strokes can almost double power of an equal displacement 4 stroke.
I will say that I couldn't even imagine how real it would get if I had a street bike with the characteristics of my old dirt bikes. Tire spinning out of every corner
I will say that I couldn't even imagine how real it would get if I had a street bike with the characteristics of my old dirt bikes. Tire spinning out of every corner
06-09-2014 | 10:54 PM
#12
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It was stupid environmental regulations that killed them, not impracticality.
06-09-2014 | 10:58 PM
#13
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Yah, and after spending $600-$1000 on every 4 stroke rebuild, and dealing with 225 moving parts, i've been back on two strokes for about 4 years and don't regret it one bit. About 5 moving parts, and $150 rebuilds.
If you think any different, then clearly you haven't had some titanium valves, a timing chain, and failed valve seats in your hands recently...
Keep buying all the new $9000 4 stroke dirtbikes, and i'll keep snatching up the used $800 2 strokes... All day long.
If you think any different, then clearly you haven't had some titanium valves, a timing chain, and failed valve seats in your hands recently...
Keep buying all the new $9000 4 stroke dirtbikes, and i'll keep snatching up the used $800 2 strokes... All day long.
06-09-2014 | 11:05 PM
#14
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Yep, I raced two-strokes on the 90's and enjoyed them quite a bit. Never had any problems with reliability from my RZ350, which was pretty heavily modified and got me a championship in '97. Funny thing is, I never really cared much for them as street bikes. Had RD350's too. Fast as hell, but never cared much for the exhaust note compared to a big 4-stroke thumper you could feel as it rode by, or the scream of a high revving 4 cylinder as it rips past. Nope, would not trade my SuperHawk for it.
06-10-2014 | 03:36 AM
#15
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I used to love 2 strokes and had many as road bikes including Air Cooled RD350, 400 and LC250,350 and a Suzuki Gt750 triple that I did 96,000k's on beforeI pulled the head and barrel.
There was no need to as all was well but I fitted new rings anyway.
I wish that we could still get them as they all punched way above their weight in terms of performance and are simple to own.
The most important thing was to use the best 2 stroke oil money could buy and have them jetted right.
Memories!!!!!!!
There was no need to as all was well but I fitted new rings anyway.
I wish that we could still get them as they all punched way above their weight in terms of performance and are simple to own.
The most important thing was to use the best 2 stroke oil money could buy and have them jetted right.
Memories!!!!!!!
06-10-2014 | 07:43 AM
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I've heard a rumor that there is some new 2 stroke technology that drastically reduces the emissions they produce. If this is true, they could come back again. I sure hope so. I love my 250r three wheeler. Even with the crappy gas we have, I've let mine sit for about a year and it would run without even putting fresh gas in it. I'd love to have one of those two stroke triples from the 70's. It would be cool to see someone do a custom superhawk build with on of those motors. Then you'd have a one of a kind rocket for sure. There you go Wolv. I provided a new project for you. Tim
06-10-2014 | 01:10 PM
#17
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I've heard a rumor that there is some new 2 stroke technology that drastically reduces the emissions they produce. If this is true, they could come back again. I sure hope so. I love my 250r three wheeler. Even with the crappy gas we have, I've let mine sit for about a year and it would run without even putting fresh gas in it. I'd love to have one of those two stroke triples from the 70's. It would be cool to see someone do a custom superhawk build with on of those motors. Then you'd have a one of a kind rocket for sure. There you go Wolv. I provided a new project for you. Tim
Here's some cool 2 strokes to add to this thread:
Jaybuilt Bellytank Tripple
Kawasaki 750 tripple cafe racer
There are also several more 2 stroke motorcycles on The Knee Slider.
06-10-2014 | 02:32 PM
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Yes there is some new reasearch on cleaner much efficient 2 strokes. Direct injection helps a lot as fuel is injected only after exhaust ports are closed.
I believe the snowmobile and jetski industry is probably doing most of the work right now.
I believe the snowmobile and jetski industry is probably doing most of the work right now.
06-10-2014 | 03:08 PM
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2smokers
Evenrude currently is the leader on production 2smokes and their PWC are even allowed on pristine Lake Geneva (ie, Lake Léman in Switzerland)...
4/8/2014*| Details | Press Releases | Evinrude.com
I still have my RD400 and rue the day I sold my Kawi H2 Mach 4 and Suzi 400 triples and Suzi Titan 500 twin.
No way 2smokes would have passed if not for the EPA!
Orbital tech is out there and technically a diesel is similar to a 2smoke but with poppet valves.
4/8/2014*| Details | Press Releases | Evinrude.com
I still have my RD400 and rue the day I sold my Kawi H2 Mach 4 and Suzi 400 triples and Suzi Titan 500 twin.
No way 2smokes would have passed if not for the EPA!
Orbital tech is out there and technically a diesel is similar to a 2smoke but with poppet valves.
06-10-2014 | 05:32 PM
#21
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Did you happen to catch the article that Sport Rider had on this bike?
320 lbs, 160 HP, and all for just a paltry $136,000. Oh, and they are making just 46 of them for the first year, and you can put down 30% to hold one right now.
Looks like another nice bike to add to Jay Leno's collection.
Boy how I LOVE my Superhawk!
320 lbs, 160 HP, and all for just a paltry $136,000. Oh, and they are making just 46 of them for the first year, and you can put down 30% to hold one right now.
Looks like another nice bike to add to Jay Leno's collection.
Boy how I LOVE my Superhawk!
06-10-2014 | 08:06 PM
#22
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Consumer choice killed 2-strokes, not the EPA. By the time they were banned in the US, there were hardly any left to ban. I don't believe there are rules against racing them off road either but most choose a 4-stroke. They're gone because they are inferior.
06-10-2014 | 08:27 PM
#23
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I don't know that i would be throwing around the word inferior. I would agree with terms like "simple", "cheap", "lightweight", "expensive to put gas in" (because of premix cost)... Inferior? No.
Dealerships and magazines convinced consumers that high revving 4 strokes required less maintenance. It's simply not true. If we were comparing honda xr series bikes and 2 strokes, then i would agree that 2 strokes require more frequent rebuilds.
Have any of you 2 stroke naysayers ever rebuilt the top end on your own late model 4 stroke? Ever done valve seats and guides? Ever played with cam timing? Cam chain tensioners? Valve spring retainers? Cam lobe profiles? The list of things to do is endless, and expensive
2 stroke top ends are very simple: squish band, port timing/height... My 12 year old helped do the top end on her kx65 two years ago when she was 10. She thought it was easy...
James
Dealerships and magazines convinced consumers that high revving 4 strokes required less maintenance. It's simply not true. If we were comparing honda xr series bikes and 2 strokes, then i would agree that 2 strokes require more frequent rebuilds.
Have any of you 2 stroke naysayers ever rebuilt the top end on your own late model 4 stroke? Ever done valve seats and guides? Ever played with cam timing? Cam chain tensioners? Valve spring retainers? Cam lobe profiles? The list of things to do is endless, and expensive
2 stroke top ends are very simple: squish band, port timing/height... My 12 year old helped do the top end on her kx65 two years ago when she was 10. She thought it was easy...
James
06-10-2014 | 11:03 PM
#24
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the bottom line is for a street bike they are far to quick to spin the tire. it would break traction constantly. IMO the break between each power stoke is what help keeps things smooth and controllable. id challenge any of you to ride a 500cc 2 stroke around a track at anywhere near the pace you can on a 4 stroke. you would land yourself in a ditch before turn 2....
think of the power of the 2 smoke dirt bikes. great fun IN THE DIRT. not so much on the asphalt where being smooth keeps you out of trouble
and if you say anything to the effect of 2 smokes are better than 4s, your just being nostalgic. people dumped their flip phones for iphones because they are better....
exhaust and intake ports are no match for valves and cams. 2 strokes are for lawn mowers and weed whackers....
if there was a market for 2 stroke bikes anymore, the powers at be in the big motor companys would never have let them get banned. the bottom line is no one wanted them anymore
think of the power of the 2 smoke dirt bikes. great fun IN THE DIRT. not so much on the asphalt where being smooth keeps you out of trouble
and if you say anything to the effect of 2 smokes are better than 4s, your just being nostalgic. people dumped their flip phones for iphones because they are better....
exhaust and intake ports are no match for valves and cams. 2 strokes are for lawn mowers and weed whackers....
if there was a market for 2 stroke bikes anymore, the powers at be in the big motor companys would never have let them get banned. the bottom line is no one wanted them anymore
06-11-2014 | 07:25 AM
#25
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It's not quite so black and white. There's no reason to use a 500cc motogp bike as an example of all 2 strokes being unrideable. What is not being talked about is the fact that those 500cc bikes were all rider, no electronics. If you added the silly things they have now, traction control, wheelie control, etc, then they would be rideable.
The same goes for current top level racebikes, if you took away traction and wheelie control, those become somewhat unrideable too.
Anything can be tuned to behave however you want. My kawasaki kdx220 2 stroke had all low end and midrange, with zero top end hit, because of port timing and the pipe i had. The trx250r i had was a midrange bike for the same reasons.
The reason the 500cc 2 strokes were crazy is because they were tuned that way, not because they had to be.
There are many other great alternatives to a 500cc 2 stroke on the street: 125s, 250s, 300s, the list goes on. The UK still has tons of two strokes, and they use smaller sizes to actually "teach" their new and young riders how to ride, rather than letting every 16 year old have an R1.
2 strokes have their place, but like i said, people are brainwashed.
James
The same goes for current top level racebikes, if you took away traction and wheelie control, those become somewhat unrideable too.
Anything can be tuned to behave however you want. My kawasaki kdx220 2 stroke had all low end and midrange, with zero top end hit, because of port timing and the pipe i had. The trx250r i had was a midrange bike for the same reasons.
The reason the 500cc 2 strokes were crazy is because they were tuned that way, not because they had to be.
There are many other great alternatives to a 500cc 2 stroke on the street: 125s, 250s, 300s, the list goes on. The UK still has tons of two strokes, and they use smaller sizes to actually "teach" their new and young riders how to ride, rather than letting every 16 year old have an R1.
2 strokes have their place, but like i said, people are brainwashed.
James
06-11-2014 | 07:54 AM
#26
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Dealerships and magazines convinced consumers that high revving 4 strokes required less maintenance. It's simply not true. If we were comparing honda xr series bikes and 2 strokes, then i would agree that 2 strokes require more frequent rebuilds.
Have any of you 2 stroke naysayers ever rebuilt the top end on your own late model 4 stroke?
Have any of you 2 stroke naysayers ever rebuilt the top end on your own late model 4 stroke?
I stand by my assertion that 2-stroke is inferior because I look at them through the lens of the average road motorcyclist, but readily volunteer that it is in part because their development has been abandoned. If I were an Mx'er, I'd be pretty salty about the cost of engine maintenance too.
To the point about 500cc 2T's and modern traction controls, when 4-stroke 990's came in, they were more powerful and more ride-albe with much better tire wear, all without traction control. Josh Hayes was winning AMA superbike up until 2-3 years ago with no electronic intervention on his R1.
Last edited by davidka; 06-11-2014 at 07:57 AM.
06-11-2014 | 08:23 AM
#27
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I must admit I don't follow top level racing as much as others.
Were lap times faster or slower on the 4 stroke 990s (when compared to the 2 stroke 500s)?
Thanks for your input. Many of my comments have been biased from a mechanic's standpoint. I spent thousands on 4 stroke top ends, and countless hours in the garage that should have been spent on my family. Now with two strokes I spend next to nothing, with practically no garage time on the engines. These experiences are entirely dirtbike/ATV related. Obviously the street going motorcycles just don't have the same issues. It's the 4 stroke dirtbikes that are eating through heads/valves, and requiring a lot more money than their 2 stroke counterparts. It pretty much started with the titanium valve craze from Yamaha and Honda.
Still no argument for way more moving parts though
James
Were lap times faster or slower on the 4 stroke 990s (when compared to the 2 stroke 500s)?
Thanks for your input. Many of my comments have been biased from a mechanic's standpoint. I spent thousands on 4 stroke top ends, and countless hours in the garage that should have been spent on my family. Now with two strokes I spend next to nothing, with practically no garage time on the engines. These experiences are entirely dirtbike/ATV related. Obviously the street going motorcycles just don't have the same issues. It's the 4 stroke dirtbikes that are eating through heads/valves, and requiring a lot more money than their 2 stroke counterparts. It pretty much started with the titanium valve craze from Yamaha and Honda.
Still no argument for way more moving parts though
James
Last edited by thedeatons; 06-11-2014 at 08:39 AM.
06-11-2014 | 10:04 AM
#28
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Inferior is a poor choice of words. Tradeoffs is perhaps a better word because 2 strokes are superior to 4 strokes in many ways, especially in terms of simplicity, cost and power to weight or displacement.
With the proliferation and popularity of sporting motorcycles today, unlike in the days when 2 strokes were killed off (and they were indeed killed off) when there was less emphasis on performance, I would wager that if a manufacturer were allowed to build and sell a state of the art sportbike with a 2 stroke engine it would sell well.
The good news is that technology has progressed so much that 4 stroke performance is ridiculously high, making the demise of 2 strokes easier to accept.
But I do miss them and certainly don't consider them inferior because, well, they aren't.
Last edited by killer5280; 06-11-2014 at 10:13 AM.
06-11-2014 | 10:28 AM
#29
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That must be why you so seldom see 2 strokes on snowmobiles or karts or why 4 strokes are allowed double the displacement of 2 strokes in order to be competitive in racing classes.
But I do miss them and certainly don't consider them inferior because, well, they aren't.
But I do miss them and certainly don't consider them inferior because, well, they aren't.
The displacement point is disingenuous. Based on firing cycles, they are the same since 2T's fire their displacement twice as many times per minute as 4T's do. That said, a 450cc 4T MX bike makes nearly as much HP as a 500cc 2T used to but it's far easier to ride.
06-11-2014 | 10:45 AM
#30
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500 2 strokes were never allowed to race with 450 4 strokes (in my recollection).
I'm certain if you asked some 450 racers whether they'd be okay going up against a 500 2 stroke they would not be for it... That is why YZ125s raced with YZ250Fs. That is also why YZ250s raced with YZ450Fs. So that math dictates the 4 stroke needs to be 45% bigger in size (CC) to achieve the same performance. And that was with a YZ250 with year 2000 engine technology, and a YZ450F with 2010 technology.
James
I'm certain if you asked some 450 racers whether they'd be okay going up against a 500 2 stroke they would not be for it... That is why YZ125s raced with YZ250Fs. That is also why YZ250s raced with YZ450Fs. So that math dictates the 4 stroke needs to be 45% bigger in size (CC) to achieve the same performance. And that was with a YZ250 with year 2000 engine technology, and a YZ450F with 2010 technology.
James
