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I am getting confused on the information regarding the true hp level of our bikes and still hopeful for a 47 rear wheel hp/54 crank hp.:D
Some dyno tests show 43 hp on rear wheel and some show 47 hp on it.
Honda Thailand informed me many times that it is 47 crank hp and dynoed and found 43- 44 hp on rear wheel but as you know, all dynos in this world give different results according to many factors even for the same bike.
I attached the dynos from Tyga Perfromance Bangkok and Leo Vince Exhausts Italy. Tyga is 43hp and Leo is 47hp on rear wheel.
I hope it is 54 hp on crank and 47 on rear wheel but i do not think so there will be changes on the engine for different countries due to cost saving.
So on this thread, please post dyno test results, your ideas and findings about the true hp level of honda cbr500/cb500f/x series bikes.
Thanks in advance for your contribution.
 

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Never heard of any manufacture giving hp figure at the wheel/wheels, if Honda say its 47hp then I think that would be a crank hp figure.
I hope I'm wrong though :)
 
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I'm not sure what the A2 licence means now either: it actually does not specify wheel or crank hahaha! Lots of debate lol.

With about a 15% loss from crank to rear wheel, if it is 47 at the crank, then that would make the 500 40hp at the wheel. That's way below the dyno results we have seen. However, if it is 54 at the crank, then that would make 47 rear wheel - dead in line with the dyno results. And also explains where this unverified "mystery 54hp" comes from.

It would also be in line with the speeds and times seen in videos: the nc700 pulls about 5 sec 0-100kph and tops out at about 180, and is a 47hp rear wheel bike this is for certain. If the 500 was 7 hp down at the rear wheel, then I don't see how it could pull the 5 sec 0-100kph, 0-135kph in <9 sec, and 6th gear roll on 120-150kph in 6-7 seconds that I have seen in many videos.

Dave
 
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Different dynos will read differently on different times different places.

With that out of the way I think the range is good enough. No need to find the exact number. It will change day to day. Depends on way too many things.
 

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I can see where you are coming from but, it sounds like typical beurocratic bumbling. Show me a link to the A2licence which explicitly states crank. Lots of confusion the web over this.

As restrictions are available and allowable, and there is no real way to dyno at the crank on an existing bike that makes rw more likely. IMHO.

Dave
 

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It comes down to HOW the "power" is measured. The ambiguity is with WHERE the measurement of "engine" power is made. Measuring at the crank is prohibitively difficult and restriction kits (which are clearly allowable) are typically calibrated according to the rear wheel measurement as far as I know.

...who knows but I do take your point :)

Dave
 
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Different dynos will read differently on different times different places.

With that out of the way I think the range is good enough. No need to find the exact number. It will change day to day. Depends on way too many things.

True, but the only two dyno figures available are 10-15% higher than what they should be if its 47 at the crank, and both are within 5% of each other :)....

Dave
 

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I can see where you are coming from but, it sounds like typical beurocratic bumbling. Show me a link to the A2licence which explicitly states crank. Lots of confusion the web over this.

As restrictions are available and allowable, and there is no real way to dyno at the crank on an existing bike that makes rw more likely. IMHO.

Dave
The A2 license specs state 'engine power'. It doesn't mention crank nor rear wheel power.
 

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That's my point :) where is it measured? That and the fact that at the crank is irrelevant, is what is delivered to the road that counts. Typical idiotic well meaning people writing poorly worded ambiguous laws.

Anyways, it really doesn't matter, the 500 is what it is and seems pretty quick :)

Davey
 

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It is true that the law passed by the EU is poorly worded, it doesn't mention 47hp (35kw) being at the wheel or the crank. If the police were to demand it checked then the only thing they could do is put it on a dyno and the check would have to be taken at the wheel.

Whether Honda have taken this into account is yet unknown, but going off what usually happens the 47hp will be measured at the crank and lose 3 hp by the time it is at the wheel.

My guess would therefore be 47hp at the crank 44hp at the wheel but until we have someone put a stock bike on the dyno and see the stats then we won't know for sure.

I should have added that it is possible to get a 70 or 80hp bike restricted to 47hp to meet the law and that would be 47hp at the wheel
 

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We have, e two that ll posted at the start of this thread: 44 and 47 hp stock. That's why I've been banging on about it ;-)

Dave
 

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We have, e two that ll posted at the start of this thread: 44 and 47 hp stock. That's why I've been banging on about it ;-)

Dave
yep, :eek:. Should have noticed. 44hp sounds right to me, but I still think if someone wanted to they could lift this to 47hp at the wheel and still be within the law. It's just the same as bigger bikes being restricted to 47hp at the wheel
 

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I saw the akropivic exhaust for the honda cbr500 and the stock gives 43.7 bhp on the dyno and their slip-on gives 44.2 bhp.
The torque and hp powerbands are very liniar and smooth. The dyno results match well with a bike with 48 bhp on the crankshaft and an efficient delivery.
 
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