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Any motorcyclists on this forum?

Two-strokes tend to have really narrow powerbands, and since older emissions standards killed them for road use I'd have to assume meeting today's far stricter limits is impossible. Meanwhile you can get 200HP/liter from a fully street-legal and smogged RSV4.
I had 5, 2 stroke rides over some years. Yes, the RM125 was peaky but the others where much more broadband because they where tuned that way. Then another example is the Suzuki water buffalo triple 750cc street bike that is reputed to have some of the smoothest power delivery. The reputation 2 strokes have is deserved but it's not factual for all of them.
 
Had a Kawasaki KR1-S back in the early 90's in Sydney, Australia. Still the fastest 250 production bike ever made.
Possibly the most fun I have had on a motorcycle. Loved it.
 
... Or, howsabout the other way round... an Aprilia RSV4 motor in a snowmobile, or a jetski?

Or just a Kawasaki H2R jet ski.
Supercharged and carbon fibre.
Yowsa.
 
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... Or, howsabout the other way round... an Aprilia RSV4 motor in a snowmobile, or a jetski?

Or just a Kawasaki H2R jet ski.
Supercharged and carbon fibre.
Yowsa.
I liked it when I mounted a pair (one to each rear wheel) of MAC 101 (2 stroke chainsaw) engines (15 [email protected] RPM, each) on a Go-Kart.
Hard to have more fun on 4 wheels than that.
It did not work so well when I mounted one of them on a mini-bike.
 
Please file under "Dude, where is the engine?" folder:
202311_VergeElectricMC.jpg

"For the specs buff, the California Edition is powered by the Verge TS Pro platform which can produce 1,000 Nm of torque with a top speed of 124 miles per hour and a 0 to 60 time of 3.5 seconds. The electric superbike also implements an Ohlins suspension system that makes the maneuvering and handling of the vehicle easier and more stable. The battery can be fully charged in just 35 minutes with its fast-charging capabilities and churns a range of up to 217 miles on a single charge."
...more importantly, it weighs under 600lbs and most is low and centrally located.
 
...more importantly, it weighs under 600lbs and most is low and centrally located.
That's still awefully heavy by todays superbike standards
My 1994 Ducati 900 Monster dry weight was 405lbs, after I replaced the heavy exhaust system
with some carbon fiber cans it was sub 400.
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My 1994 Ducati 900 Monster dry weight was 405lbs...
...after I replaced the heavy exhaust system with some carbon fiber cans it was sub 400.
Can your Duckie generate instant 740 foot-pounds of torque?? That is a silly-*ss number but a number still.
202311_AllYourBase.png

Good morning, Mr. Hunt. Your options, should you choose to accept them...
You can have 370ft-lbs and they can probably chop-off the top half of the battery pack or they can give you 108 mile of range @280 pounds of dry/wet[?] weight.
They can also probably provide you with a fake carbon-fiber exhaust system... if you really need one!
MQA and autonomous motorcycling will be the next most-wanted features soon.
:cool:
 
Can your Duckie generate instant 740 foot-pounds of torque?? That is a silly-*ss number but a number still.
Just what the world needs is faster more powerful motorcycles.
There's at least 1/2 dozen ICE around with 200+ mph top ends and many are electronically regulated to
not exceed that number by much. Just stupid numbers that will equate an uncontrollable vehicle.
 
Can your Duckie generate instant 740 foot-pounds of torque?? That is a silly-*ss number but a number still.
...
Torque is not conserved through the drivetrain, so to be precise let's say torque at the rear wheel. 740 ft. lbs. at the rear wheel is almost certainly more than you can use because it exceeds available traction. And of course that torque is less at high speeds due to gearing.

And 740 ft.lbs. at the rear wheel isn't unique to electrics. Consider a typical ICE motorbike having 1st gear ratio of roughly 3:1 and final drive of 3:1 giving a total of 9:1 reduction. If the engine makes 100 ft.lbs. at the crank that's 900 ft.lbs. at the rear wheel. Sure the torque curve isn't flat, but that is actually a good thing when you're traction limited.
Just what the world needs is faster more powerful motorcycles.
There's at least 1/2 dozen ICE around with 200+ mph top ends and many are electronically regulated to not exceed that number by much. Just stupid numbers that will equate an uncontrollable vehicle.
Sarcasm noted, and agreed.
 
217 mile range and 600lbs wouldn't be bad, for a sport tourer. That's not dressed as a sport tourer, nor are e-bike recharge times great for sport touring. 3.5s 0-60 and 125MPH max speed are... rather underwhelming; this is why gimmickry of the rear hub aside (and it's a neat gimmick) some of the other e-moto vendors have stuck to 6-speed gearboxes.

My bike has well south of 740 ft-lbs and with launch and wheelie control, and with me leaning way forward on the bars, it still has to power limit to keep me from wearing it like a hat. I don't know what you do with 740 ft-lbs other than lurid burnouts.
 
The dealer I bought my 1290 sas from started carried zero and I was asking if it was a useful replacement for my 1290 SDR evo and after I told him i like to do 400 mile days he said the electric bikes weren't really an option for me. I haven't heard any of those numbers being boasted for their bikes yet, but they're supposed to be fast.
also trying to understand how 100 ft lbs at crank translates to 900 at wheel?
 
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I can’t even remember if I replied to this before. KLR 650 and 2004 Ducati Multistrada.
 

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also trying to understand how 100 ft lbs at crank translates to 900 at wheel?
I don't know about his numbers but he refers to torque multiplication thru gearing, that's why ICE vehicles need transmissions.
HP/Torque numbers are measured either at engine crankshaft of the rear wheel in top gear.
 
I don't know about his numbers but he refers to torque multiplication thru gearing, that's why ICE vehicles need transmissions.
HP/Torque numbers are measured either at engine crankshaft of the rear wheel in top gear.
True, but there's a key difference that some people don't realize.

Power is conserved, so power at the crankshaft equals power at the drive wheels (minus friction/inertia losses).
Torque is not conserved so torque at the drive wheels is R times torque at the crankshaft, where R is the total gear ratio (crankshaft revolutions / wheel revolution).

Theoretically speaking, a bike (or car) with a 100 HP engine has 100 HP at every point in the drivetrain from the crankshaft to the wheels (well more like 85 HP at the wheels after losses). But an engine with 100 ft. lbs. of torque could have 1,000 ft.lbs. of torque or more at the drive wheels in low gear, to less than 100 ft.lbs. in top gear. All depends on the gear ratios.

So when people quote torque numbers, they need to specify whether it is crankshaft torque or drive wheel torque. The difference can be an order of magnitude or more! This is true of electric motors too, since the motor itself may spin at 20,000 RPM or more.
 
... also trying to understand how 100 ft lbs at crank translates to 900 at wheel?
Basic physics. Gearing trades torque for speed, leaving power unchanged. If gear A drives gear B at a 2:1 ratio (gear A has half as many teeth), then gear B spins at half the speed with twice the torque as gear A. And vice versa. Power is torque * RPM so it is unchanged - half the speed at twice the torque makes the same power.

Power tells you what the engine can do. Torque just tells you what RPM and gearing you need to make it happen.
 
A chain drive modern motorcycle loses 10-12% at the back tire generally agreed, right. Electric engines have instant torque, but I don't thing they're any less immune to gravity and wind resistance than any other machine. If yoiur electric motor could make 900 ft/lbs in 5-6th gear it could and would overcome aerodynamic force and be capable of several hundred mph, I don't think i'm following what you're saying.
 
post 595 is my understanding.
 
egadz!
I posted that brand-new (LA AutoShow display photo @post#585) Verge e-Bike for the gear heads that may have appreciated the current tech that opens novel approaches without excessive added weight (including the lack of gears) and it ended up getting pooh-pooh'ed and not one Like... :confused:
 

If I win the lottery I'd like the Mugen...If it was for sale.

Probably a bit of a hassle adding lights etc, but worth it most likely.
Or just keep it as an eco track bike.
 
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egadz!
I posted that brand-new (LA AutoShow display photo @post#585) Verge e-Bike for the gear heads that may have appreciated the current tech that opens novel approaches without excessive added weight (including the lack of gears) and it ended up getting pooh-pooh'ed and not one Like... :confused:
I could be wrong but I don't see E-motorcycles ever getting too big until ICE vehicles are outlawed.
A big part of riding them is the sound and feel of the power.
 
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