Vins emissions-legal 2-stroke sport bike

[davidji]

75hp 250 v-twin, 231#, . Will you be able to buy one here? We'll see...

https://www.rideapart.com/articles/...brPai0Vp9bg0VxnwutTIFn0jI0p1Pqnf9vOXR8nn48i94

 

[ScottRNelson]

Next to last paragraph says all we need to know:

Sadly, we probably won’t see this bike in North America any time soon. Vins says the bike will hit the UK early in 2020, but pricing is a long way off. Spoiler alert: It will be expensive.

 

[gixxerjeff]

Cat converter efficiency and direct injection are our friends....but yes, hurdles remain.

 

[Shaggy]

Where is the dude who built the 500cc 2T R6?

 

[gixxerjeff]

I think you mean this guy?
https://www.bayarearidersforum.com/forums/member.php?u=47202

 

[bpw]

99% it winds up being pretty much vapor-ware, going from building a one-off in your garage to actually selling a street legal motorcycle takes piles of money.

Might make a few as a super low production, essentially custom build that allows it to fly under the regulatory radar, but we won't be buying 70hp, 230lbs street legal bikes anytime soon.

 

[Blankpage]

That's the bike I wanted 20 years ago. There are actually many 4 strokes now that I would rather have.

 

[banshee01]

Are off road dirtbikes subject to Euro 5? How does that work over there?

I have had hopes for the new fuel injected oil injected ktm dirtbikes getting a CA plate.

I mean these ktm 500 are CA plated from the factory how far behind are the new 2 strokes they have in terms of emissions?

 

[2strokeYardSale]

That thing uses YZ125 cylinders on custom cases. Supposedly the street bike will cost 40K Euros and the track bike 50K.

 

[bpw]

Are off road dirtbikes subject to Euro 5? How does that work over there?

I have had hopes for the new fuel injected oil injected ktm dirtbikes getting a CA plate.

I mean these ktm 500 are CA plated from the factory how far behind are the new 2 strokes they have in terms of emissions?

I looked at the emissions numbers a couple years ago, short answer is even a really clean, modern two stroke is more polluting than a a diesel bus. Not even close to meeting modern road emissions standards.

 

[89fj]

yes, please

 

[ilikefood]

Question - is the reason that 2-strokes are lighter just the that a 2-stroke engine weighs that much less than a 4-stroke engine? A 4-stroke bike with 75hp would weigh at least 100 lbs more (Husky 701 SM has about that much power and weighs about 330 lbs). Or is this bike so light because other components are much lighter than a typical bike? In which case a 4-stroke bike could come close to that weight?

I mean, I know that 2-stroke engines are lighter because they’re simpler and have 2x the power strokes per revolution, but is the difference in engine weight that big, at 100+ lbs?

 

[R3DS!X]

A man can dream.

 

[R3DS!X]

Question - is the reason that 2-strokes are lighter just the that a 2-stroke engine weighs that much less than a 4-stroke engine? A 4-stroke bike with 75hp would weigh at least 100 lbs more (Husky 701 SM has about that much power and weighs about 330 lbs). Or is this bike so light because other components are much lighter than a typical bike? In which case a 4-stroke bike could come close to that weight?

I mean, I know that 2-stroke engines are lighter because they’re simpler and have 2x the power strokes per revolution, but is the difference in engine weight that big, at 100+ lbs?

That specific bike has much more money thrown at it for other parts to be very lightweight vs a mass market production bike.

If you compared a modern KTM 2 vs 4 stroke the weight differences are a lot closer because the price and class of bike is a lot closer.

 

[ScottRNelson]

Question - is the reason that 2-strokes are lighter just the that a 2-stroke engine weighs that much less than a 4-stroke engine? A 4-stroke bike with 75hp would weigh at least 100 lbs more (Husky 701 SM has about that much power and weighs about 330 lbs). Or is this bike so light because other components are much lighter than a typical bike? In which case a 4-stroke bike could come close to that weight?

I mean, I know that 2-stroke engines are lighter because they’re simpler and have 2x the power strokes per revolution, but is the difference in engine weight that big, at 100+ lbs?

The cylinder head on a two-stroke engine is significantly lighter. No valves, camshafts, tappets, rocker arms, or gears. Just enough metal to hold the combustion pressure, a spark plug, and whatever it takes to cool it (fins or water passages). The cylinder itself is going to be heavier because it has the intake and exhaust passages. I think the crank is usually heavier, but I can't justify that argument. There is a bit more stuff in the crankcase because the intake air/fuel goes through there. The pistons have much bigger skirts, so they're heavier.

But the stuff in the cylinder head dominates the weight difference.

 

[ST Guy]

Not sure if this is accurate, but as I recall, one of the reasons that manufacturers embraced 4 stroke engines for road racing at the highest levels is that they could build big bang engines much easier and big bang engines are supposedly easier to ride at the ragged edge of traction.

 

[JesasaurusRex]

Are off road dirtbikes subject to Euro 5? How does that work over there?

I have had hopes for the new fuel injected oil injected ktm dirtbikes getting a CA plate.

I mean these ktm 500 are CA plated from the factory how far behind are the new 2 strokes they have in terms of emissions?

:cool

 

[JesasaurusRex]

The cylinder head on a two-stroke engine is significantly lighter. No valves, camshafts, tappets, rocker arms, or gears. Just enough metal to hold the combustion pressure, a spark plug, and whatever it takes to cool it (fins or water passages). The cylinder itself is going to be heavier because it has the intake and exhaust passages. I think the crank is usually heavier, but I can't justify that argument. There is a bit more stuff in the crankcase because the intake air/fuel goes through there. The pistons have much bigger skirts, so they're heavier.

But the stuff in the cylinder head dominates the weight difference.

I don't disagree with the parts list, but there's not 100lb difference between a 250 two stroke and a 450 four stroke, not even close.

Google
TC250 weight = 211.6 lbs
FC250 weight = 217.8 lbs
FC450 weight = 222.7 lbs

so
6 lbs difference for equal displacement
11 lbs for twice the displacement

now there are probably a couple other subtle differences between the bikes to add or subtract a lb or two from the above weight comparison, but still, def not 100 lbs no matter how you slice it

 

[ScottRNelson]

def not 100 lbs no matter how you slice it

Where is this "100 lbs" coming from? I never mentioned a weight value.

 

[JesasaurusRex]

Where is this "100 lbs" coming from? I never mentioned a weight value.

Sorry, thought you were cosigning the 100 lbs. To elaborate on that the 701 weighs 100 lbs more than a 2t dirt bike for reasons other than it being a 4 stroke bike.