1ltr car vs 1ltr bike engines

[rac3r]

Stupid question but why do car engines produce so little power compared to the equivelant bike engine?

Eg my 1.4 car produces 95bhp whereas my 636 produces the same if not more!
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Bikes : 2006 CBR125R - 2004 Monster 620ie - 2004 ZX-6R B1H - 2005 Monster S2R 800 - 2011 Street Triple - 2009 Streetfighter 1098 - 2014 ZX-6R 636

[Irezumi aka Reuben]

Your bike has to shift around 350kg give or take a bit, your car 1500+kg give or take a bit.
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Pictorgraphicalfantastical

[P.addy]

Your bike can rev to 13k, your car revs to 6k.

Horses for courses, bikes are built that way, cars are for transporting shit.

[hmmmnz]

the little 3 cylinder focus ecoboost 1 litre motor makes 125hp
which aint bad, my 850 tdm only makes 60hp odd,

a car motor is tuned to provide power and torque at lower rpms,
and to provide reliability,

you'd struggle to keep a 1000cc 200hp engine reliable for 100k+ miles
with no major work, especially if it was constantly hauling 850-1500kgs around all the time
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the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[Knacker]

My 4.7 V8 Produces a mind boggling 235bhp which is pretty pathetic considering your 1.4 makes 95bhp.

It's a bit like asking why a RS125 makes XXbhp and my GS125 makes 11bhp.
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Current: Gsxr 600 Srad - GS125 - DT125
Previous: K1 GSXR 1000

[mattyfattyboo...]

Different purposes for each motor.

[Tungtvann]

Cars have a lot more torque too, producing the power at lower revs, making them easier to drive and actually pull the weight of a car. Sticking an equivalent HP motorbike engine into a car, say a GSXR600 engine into a 1.4 Ford Fiesta probably wouldn't make it that good to drive!

[G]

[rac3r]

My car (Mito) they do the same engine but with a turbo in 155hp form. Also a slightly different 1.4 Turbo in 170hp form!
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Bikes : 2006 CBR125R - 2004 Monster 620ie - 2004 ZX-6R B1H - 2005 Monster S2R 800 - 2011 Street Triple - 2009 Streetfighter 1098 - 2014 ZX-6R 636

[arry]

[Kickstart]

Hi

More revs, and as power is torque x rpm that is how to make power.

But a higher revving engine is likely to be more highly stressed (and shorted lived) and have a bigger difference between low down rpm torque and top end rpm torque. More weight for the car means more torque needed at low rpm to move off, which without very low gearing makes limited torque at low rpm less useful.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[stevo as b4]

As Keith said really.

Car manufacturers cannot afford the build costs (both materials specs and tolerances) of a 1.0L motor that revs high enough to make 100+ bhp as a primary reason, let alone the reduced service intervals, and shorter lifespan.

Revs are always expensive, Forced induction can be cheap to a point until you go too far and then it gets suddenly and catastrophically expensive!

[Llama-Farmer]

Modern bike engines are built to much finer tolerances, with much higher specific power output. But they don't have to lug around a tonne and a half of metal.


Car engines do have to drag that extra weight, and they will usually clock up more miles than a bike engine, and generally taken less care of than a bike engine.




So car engines are built to provide much more torque than bikes, otherwise they wouldn't go anywhere.

Look at the kind of power n/a formula one engines were producing from 2.4(?) V8s. But they had to be in the right gear at the right time. This years F1 engines are turbocharged and they can be in one of several gears and they'll just pull and pull, or spin.
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Current Bike: 1999 Honda CB600 FX Hornet
Next Bike: I want a CBR-RR. And I want an F800 GS-A. And a VFR 800. Can I have all 3?
Dream Bikes: Honda VFR750R RC30, Honda NSR500, Ducati 996 R

[arry]

[weasley]

[weasley]

[Llama-Farmer]

[esullivan]

The NC, which I ride, is an interesting example of mixing the two. It's a motorcycle with a car-like engine. Although it's apparently not "half a Honda Jazz engine" as rumoured, it uses similar technology and has a similar rev limit (6.5K).

It was a controversial, but relatively successful (judging from sales) experiment by Honda. It gives the NC good fuel economy, decent torque and long service intervals, but at the expense of top-end power. I wouldn't be surprised if other manufacturers try something similar. Suzuki has cars that it could borrow from, for example.

Back in the 1980s, I used a car called the Chevy Sprint (it went by various other names, I think Geo Metro here). It apparently used an engine with motorcycle tech in it. It was like driving a golf cart. I used to say that I needed to turn the radio down to go up steep hills, but I was only half joking. Great mileage, though. 60mpg (American mpg), very easily.
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Current: '14 VFR800X Test passed 31/10/12.
Previous: '12 NC700S, '11 CBF 125, '04 SH 125.

[P.addy]

[Kickstart]

[0l0dom0l0]

Ford have also just released a new version of the 1.0l ecoboost which produces 140PS. Not bad really!
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CBT Passed: 30/08/2009, Theory Passed: 31/08/2010, Mod 1 Passed: 6/9/2010, Mod 2 Passed: 13/09/2010. Restriction ended 13/09/2012.

Bikes: 2007 Derbi GPR 50, 1998 Yamaha Fazer 600 (written off), 2002 Yamaha Fazer 600, 1994 CBR 600F, 2003 Triumph Daytona 600, Kawasaki ZX6R J1.....Current: 2006 Yamaha FZ6, 1998 Suzuki TL1000R and a Honda VFR 400 NC30.

[TallPaul_S]

Torque.

That 138bhp ecoboost engine has 155lb/ft of torque.

The S1000R has 160bhp but only 83lb/ft of torque. Even a Monster 1200S doesn't have much more torque (145bhp and 92lb/ft of torque)

An engine that doesn't need to built for torque can be built for power.

Stick that 1.0 ecoboost engine in a bike and the front tyre would last a lifetime
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00 Honda VFR800 | 09 Aprilia Tuono Factory
CBT 06/03/2014 | Mod 1 and Mod 2 passed 15/10/2014

[Kickstart]

[talkToTheHat]

Note that power = torque * RPM

Further note that hardly drivablesons and similar also have engines that produce peak torque at very low rpm.

An engine that has a reasonably wide and flat torque curve is easy and forgiving to drive, one with a steep curve that peaks briefly at high revs will probably be a whole lot more fun.

Domestic and comercial car and van engines are designed to be forgotten about for as long as possible, and owned by people who can't change a brake light or check a fluid level. Minimal maintenance.

Performance vehicles have shorter service intervals. Track vehicles this is often a handful of hours. A motorcycle is by default a performance vehicle, a 10hp 125 will spend its entire life with the throttle pinned screaming for mercy until the vehicle isncreashed beyond repair. On a sportrsbike every gram of excess weight has been trimmed and the engine is in a high state of tune.

If even the relatively unsophisticated twin in my nail was swapped into my mother's polo, she'd either kill it in months, or lose the plot at the among of valve clearance and carb balace checks that area on the service schedule. I think she checks her tyre pressures about as often, and even that is a major hastle.

How many cagers have never taken their vehicle into the second half of the rev range?
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Bandit. does. everything.

[Albigularis]