HP & Torque Thoughts

[Zed]

Is it important to you to know exactly how powerful your motorcycle is? If you have it dynotuned and find out the performance does it change your attitude towards your bike & maybe even the way you ride it?

I've always been one to "feel" the power in my bike and know whether or not it is grunty, and I can't say that I've done much modifying over the years. Now that I am getting some mods done to my bike I am curious to know its stats, even though I won't be able to campare it to what it was like originally because I didn't ever have it dynoed. Stock standard these CBR's claim to put out:

CBR600F
Specifications

CBR600F - 200014 - E

Specifications CBR600F (ED-type)

Engine Liquid-cooled 4-stroke 16-valve DOHC inline-4

Bore ´ Stroke 67 ´ 42.5mm

Displacement 599cm3

Compression Ratio 12 : 1

Carburettors 36.5mm slanted flat-slide CV-type ´ 4

Max. Power Output

106PS/12,500rpm (95/1/EC) (78kW/12,500min-1)

110PS/12,500rpm (DIN) (81kW/12,500min-1)

Max. Torque

6.6kg-m/10,500rpm (95/1/EC) (65Nm/10,500min-1)

6.8kg-m/10,500rpm (DIN) (67Nm/10,500min-1)

Will be interesting to me to see my change in perspective about knowing exactly how powerful my bike is.


Zed

[White trash]

Nup. Not important to me. I couldn't give a rats arse.

I was still sticking in the slipstream of Gixxer 1Ks at Pukekohe a couple months ago and I'm pretty sure I've only got 2/3 their power.

[vifferman]

I think that knowing that is only important for "bench racing", or maybe ego masturbation. What's more important is how it rides - whether the power it does have is usable, is enough for what I want to do, etc. For that reason, I've regeared my last two bikes, and fiddled about with the tuning (shimmed the needles etc.) to eliminate flat spots, backfiring on deceleration, etc. I'm not racing, so I don't need every last poofteenth of power available, nor do I need to know if it's more powerful than other VTRs (what's the point of that, when it's less powerful than other V-twins on the market?) I do know that it has more power than the three other VTRs I've ridden, but that's measured solely by the seatofthepantsometer and the wheeliometer.

[Motoracer]

Is it important to you to know exactly how powerful your motorcycle is?

Nup, not at the moment. I know that the only thing holding me back from being right up there in F2 is me and not my bike. I feel good about not having to worry about the bike cause I know that it is powerful enough, so all I need to do is improve my skill level.

I can confirm this cause after exiting Castrol at Pukie, I was chasing a ZX-6R racer who does 61s, I stayed with him for the whole of the back striaght right up to the braking point for the hairpin. Then I had to say , as he flew past a few more meters before anchoring it and attacking the hairpin like nothing I had ever seen before!

[Jackrat]

I guess if your going to spend bucks, your going to want to know if the moneys been well spent.
I've never been interested in facts an figures myself,but if I wanted a more powerfull bike and was spending heaps it would simply be good to know.

[merv]

Zed, shame you didn't have a base set of numbers to compare with. I know its insurance paying so not quite as important as if you were spending your own money you'd want to get your monies worth.

Me, I'm a bit the other way, never bother modifying my bikes (too tight eh!). Just keep them in top shape and if I want to go faster just open the throttle. Reason I say this is we all know the power curve climbs all the way up to the peak power point. I don't race these days (and when I did it was in the dirt) and can ask how often do I ride at the peak of power? Rarely.

In my days doing enduros one of the fastest rides we did was in Waitarere forest - those long sand straights. I found I could ride past most people (I was lighter then eh!) and they'd say "what you done to your XR?", I'd say "nothing, just open the throttle and hang on". I must have been the only person in NZ running a stock muffler. Don't ask me about what happened in rough going though, I was slower there than I'd like due to lack of fitness, but then I'd be riding through the tight tree bits at nothing like peak power rpm. So what use would a hot pipe have been to me? Certainly no use on the wallet.

With Spud and his mates about he doesn't want me riding my VFR above 100km/hr which is 4,500rpm which its probably turning out about 35hp at if on the throttle and probably sweet f'all given the light throttle you've got to use to stay at that speed - maybe 10 - 15hp.

I've already given my WR a squirt on a sealed surface and found it easily does 160km/hr before I buttoned off and how many times am I going to hit that speed in the dirt? Does it need a hot pipe? Nah, its way fast enough now.

Would I dyno them? No need, too old to worry about it now.

[Hoon]

I reckon its important not only from a racer perspective but also a street rider.

If the specs say your bike should put out 100bhp but when you get it dynoed it only says 90 bhp, you know straight away that theres a problem that needs to be fixed (lets ignore dyno inconsistencies for now). A lot of people buy their bike, then read somewhere what the claimed output is and then automatically assume that is how much power THEIR bike is making.

The fact is on a good day, a good bike which has just rolled out off the factory floor might make close to that (once again ignoring factory inflated figures or deflated in the case of govt restrictions) but most the time the bike will be way off its optimum due to slack factory tolerances (and wear if its not new). Plus, Yagasumo who was on the milling machine that day might be fuming over the 200 yen he lost playing mah jong at lunch and not paying enough attention to what he was doing!

Anyway I reckon its important to know how much power your bike is putting out as it gives you a general idea of the state of tune and wear it is in. If you go throwing dynojet kits and race exhausts which promise 10 bhp increase before getting it sorted you will only reap a portion of those benefits.

Also theres a lot of piece of mind in knowing your bike is running sweet as and near optimum if you can get close to the claimed output!!!

[Drunken Monkey]

I think the dyno charts inthemselves aren't necessarily important, but, especially if you're racing, the data, combined with your seat-o-pants-ometer can tell you some useful information. You may make a change which, for whatever reason, makes you feel faster, then find your track times have dropped a second. A dyno chart may show you are building more mid-range power and torque, but you started suffering at the top. Seat-o-pants-ometers can at times pick up the most tiniest of differences, and other times miss some obvious changes - they're not exactly scientific.
Also, if you're going to spend the money on an after market EFI computer/tuner, you might as well get the best out of it, as 'generic' maps may not be best suited to the quirks of your particular machine.
The only other thing I can think of is from a diagnostic perspective (as per Hoon's comment) = you may find you're a lucky bugger who got a few more horsies than the other new bike buyers for whatever reason, or perhaps ended up with a lemon.

If you've got the cash to burn on a dyno test, go for it. Then you'll know for sure if it's you. It's also not like you'll get nothing out of it at all...

[DEATH_INC.]

I've done a few runs over the years,the gixx the 12 and of course the turbo.The gixx was just to see what it had,same with the 12,but the turbo was more diagnostic,playing with stuff to see what worked.That's where the dyno shines,try holding on with one hand at 200+kph trying to adjust a fuel map with the other.....

[Mooch]

Zed ,
If your moding your bike for more power then it's worthwhile getting dyno runs done , that way you'll know if your moneys well spent .
Use this site for your stock starting point.

http://www.sportrider.com/bikes/146_..._Measurements/

As for how important HP / torque is , Doesn't make me ride any better or worse and there's pently of bikes with a ton more power. More importantly there's pently of riders who can out ride me using half the HP (Eh paulinnz !)
A few of us had our bikes dyno'd at motormart , it was more about seeing where the bikes power was at compared to manufactures specs and a bit of fun .

Looked something like this.

Yamaha FZ1 143 hp , 123 bhp (Standard)
MV Augusta 135 hp , 114 bhp (Standard)
Ducati 748R 106 hp , 104 bhp (Lots of mods but not sorted)
Last week
Ducati 748R 106hp 110bhp ( Sorted part throttle fueling I hope)
The power isn't important , I'm trying to get the bike sorted in the 4.5 k to 7 k region where it's riden most of the time.

Out of general interest , any of you hyper bike riders had your bikes dyno'd ? R1's GSXR's ZX12's ?.

[vifferman]

There's one problem with the latest crop of 'hyperbikes' that use ram-air to gain a few extra ponies: the dyno doesn't allow for this. There was a recent test in Sport Rider http://www.sportrider.com/tech/146_9912_ram/ where they tried to simulate this, and the best they could do was using a compressed air hose, as even the most powerful fans didn't work properly to simulate riding at speed. I guess the factories either use computer modelling, or buy some wind-tunnel time, or both.

[Motu]

I had my Honda dynoed before and after I made a set of mufflers for it,just to see if I lost or gained HP,I'm not really interested in what it puts out,but it was interesting to see the power curve.It;s not so much what it puts out,but how it does it,a stunning motor.

I've always been interested in the laptop dynos like Homedyno - these mimic the inertia dyno - with a pick up off an ign point you just do standing start run,then feed in the variables,like weight,tyre circumferance,gearing.Some of them you can take out on the track(trackdyno) and map your HP for all points of the track.Do a google on those key words,I haven't looked at them for a while,but are very cheap for what they can do.

[DEATH_INC.]

Out of general interest , any of you hyper bike riders had your bikes dyno'd ? R1's GSXR's ZX12's ?.

My ZX12(2000)dyno'd at 157hp,stock apart from a kerker can and modded tailpipe.
The gixx at 118 with just a kerker can,119 with a full rs3 yoshi system......

[geoffm]

"What'll it do, Mister" is the reason I made my dyno originally (and then the project gained a life of it's own...)
http://pages.quicksilver.net.nz/geoffm/

It is very interesting, and lots of little gains add up, and you would never feel the difference. Moreover, the way the power is developed is also important - a flat spot or peaky delivery "feels" more powerful.

The dyno black box can also be used for an onboard datalogger of racing - I have the loom and software for it but never used it for that purpose, as I ran out of money for racing around then. One day I will take it out for a track day.
Guess I am a geek...
Geoff

[bluninja]

Dynos are a good way to stop you lying about your riding....Returning to Manfeild to race for the first time after a triple thumb fracture I expected to be slow, but at the next meet I was even slower and I had 400s leaving me out of slower corners. I had it popped on the dyno at the track and it was making 64 bhp absolutely stock. So i was me riding like a nana.....no more blaming the bike.....there was a 130kg guy on a 400 pissing all over me too so I knew it wasn't just that I was a bloater either

Would agree about power delivery...my old zx9 was reasonable till I hit the spot when it took off at warp speed...fantastic FEELING of acceleration. The RSVR by comparison felt tame...the power just poured on from start to finish...I was going just as fast but it felt easy.

TTFN