Woo fooking hoo - 102.3 bhp !!!!!

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phuk72
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Post by phuk72 » Wed May 09, 2007 11:47 am

burty wrote:Well I don't believe 79bhp at the wheel with essentially no engine mods.

Unless the Akrapovic does release that much extra. I'd always thought that the standard downpipes were pretty restrictive but I got the impression that it was only me that thought that way.
I personally would suggest that the dyno readings showing 79bhp are a touch optimistic but I say this based on the torque readings not the bhp. A figure in excess of 60 is more than a number of tuned bikes make (inc mine and Honks!)

A full Akra system does release a good bit of power on the TRX and I have seen that in action on a dynojet dyno. That started at 72 rwhp and eventually ended up with 77rwhp. But that was spending a lot of money and changing a number of end cans around to find the optimum power.
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rs1800

Post by rs1800 » Wed May 09, 2007 12:21 pm

Ill check with the dyno where that power is supposed to be.

rs1800

Post by rs1800 » Wed May 09, 2007 1:10 pm

I just called them and they say it is at the rear wheel. Has anyone else used Dynotech in Bramley to get a comparison?

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Post by Quan-Time » Wed May 09, 2007 1:43 pm

dyno is always measured @ rear wheel.. unless you use an engine dyno.

OK.. theres a few things you should know about dyno runs.

1: temp
2: elevation
3: engine temp
4: fuel

these 4 things alone are not much,, but they CAN produce up to... ~5% EACH on hp figgures.

1: cold air VS hot air... obviously colder is better..

anyone know the subaru WRX cars ? put one to 15psi boost, but otherwise totally stock.. tune it up.. OK.. now run it on a very cold night AKA street race at 2am.. guess what, it dies in the ass (well in australia it does, coz we are so hot over here).. what happens is it "over blows".. meaning the air is SO cold, it is more dence, over compresses, and WHAM you get 16psi, the waste gate empties its load, you need to re-spool the turbo, repeat a few times.. Basically turbo comes on, instantly blows off, you get uber lag, repeat a few times.. way annoying.

2: dense air (sea level) VS thin air (high mountain)

Where i live is sea level, and actually LOWER than sea level at some places.. We (as a race team) travel to northern race tracks, are elevated several hundred meters and the air thins out.. thus air-fuel mixtures need to be adjusted to compensate.. VERY common.

3: engine temp

Hottest bottom end with coolest top end (head / inlet induction system).

NASCAR has been putting bags of ice on their inlet manifold for years just before they go out to get a good run.. So DONT warm up your engine, instead use an electrical heater on the oil (warming up an engine is ONLY to heat the oil, NOT the components, good parts DONT swell / move with heat). Its common practice to get a car into the pits, have a separate line for head / block.. So run fresh "tap" water thru the head, while the engine is running.. This means the inlet / head WONT heat up at all.. infact it will be COLD to the touch.. surprisingly useful for "hot laps"..
yes, theres an UBER good way to cheat with this, yes i know it, no i wont tell you, no it doesnt involve ice.. and i can use it after 5+ hrs of racing ;) DURING the race... go figgure

4: fuel types
simply put, different fuels are different power. Australia "legally" all you can get is 98 octane now.. we still have many others, like avgas (100) but you need a licence, and cant drive on the street with it.. altho HEAPS do. and then you get onto exotics, such as "race" fuels that go upto 112 octane. sure i can get it and use it reguarly,, but i only use 98 "pump" in my bike... the "regular unleaded" is 92-95..
this rating is given because ALL fuel losses its "zing" over time.. best way to measure this is via a multi meter.. wont tell you how, but yer, you can measure, easily, the octane rating of fuel,, and its decay over time.

Within 6 weeks you can go from 98 to 94 octane.. thats a fair bit of power.. but you got 98 at the pump ? but how long was it in the tank at the servo for ?? go figgure (its why racers know to measure first, and add some "octane boosters" to put their fuel at the top of the listing for the catagory they race in..)
also note, octane booster does nothing for fuels that are "new".. so a octane booster in 100oct does nothing.. it just "re-activates" the octane already in there.. so if its 92, you put booster in, it WONT add more, it just chemically "activates" it back to normal.. watch out for the extra chemicals in fuel tho,, you need to play with this a touch.. but for normal bikes / cars, you neednt bother.. but for "omg i have a 500hp engine, and need that extra 1hp" then you can touch it up, but even for us (my team) its worthless far as i know.

hope this helps..

summary: 102+ hp is UBER and gratz for that number.. but remember you can fake 5% on some conditions.. so bring that engine to australia and re-test, take to japan, cheeseland (switz) and pommyville, you will always get different, EVEN with a "perfect" tune.. some places only allow so much air/fuel/power.. its just mother nature..

prolly why everyone hates their mother-in-law..

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EDIT
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5% seems a bit over 100hp.. but ive known some 500hp engines to loose 150hp for incorrect timing.. sure it was spot on, not even the dyno run showed it, but some uber engineer geek figgured it out and WHAM 150hp came back.. im not sure WHERE it was lost. but nothing much was changed.. so im told.. but saying that, race teams do inherently lie.
mental note: NASCAR race.. DONT read the tacho.. you think 9800rpm ? HARHAH... do some homework. they DONT run that rpm all day every day for the race.. ill let you in on a secret.. they are deliberatly MIS-TUNED. most run aronud 7200rpm,, some even less. and yes, theres a reason for this aswell ;)
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Post by HansJ » Wed May 09, 2007 1:58 pm

agree with all above, except the last part. In my book, high octane is only to prevent self-ignition (wtf is the word in English?), run on as low octane as possible without the engine doing the the "self-ignition". There's definitely not more oomph in high octane petrol itself, it only gives the possibility to run higher compression, more pre-ignition or higher turbo/compressor boost. Even heard that low-octane should have more oomph, because it's got less additives, but if true, I think it's marginal. So, I don't think we have to consider the octane in TRX dyno discussions.

And temperature and air pressure is something the Dyno operator should compensate for, in theory. But for some reason they all seem to adjust it towards the positive side, go figure... But sure, air temp is crucial, some dyno workshops have special fresh air intakes, others run woth the oil-hazy workshop air...
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Post by Quan-Time » Wed May 09, 2007 2:08 pm

english word is "detonation" which is bad.. lower octane is actually prefered as you know.. BUT in some cases higher is better (2 stroke for instance)

also, dyno opperators DO know to "adjust" for day to day conditions.. i will admit that many here in australia DONT.. they do it on setup for the morning "turn on all electric equipment" at 7am.. but they dont "recalibrate" each hour as the sun REALLY gets its heat on.. etc... effects are rampant here.. thus, we only use "certified" dyno houses.. many are, but its weird that some dont do it.. non-surprisingly, they produce some crazy numbers, cars / bikes run on cert'd dynos, get lower numbers and find they have ignition / mixture issues..

i do however believe that euro has GREAT dynos.. as australia is an island, it means we cant easily go over to new zeland or asia for parts / race / dynos.. but euro has that luxury, thus, everyone is "honest"...
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Post by burty » Wed May 09, 2007 3:25 pm

Quan-Time wrote:dyno is always measured @ rear wheel.. unless you use an engine dyno.
Of course this is true, but many will quote a 'estimated' crank figure based on the measured one.

I have been led to believe that Dynojet dynos have no regular calibration.

Of course there is no traceability back to any standard anyway. However other dynos aparrently have a better attitude to calibration.

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Post by Greg » Wed May 09, 2007 4:42 pm

The way I read it (and I'm prolly talking through my socks here) is that as long as you use the same dyno for your testing, then you'll get consistent results. It's a bit like my Mrs and bathroom scales - she kept buying new scales cos 'they weren't accurate', well who gives a f*ck so long as when you get on the SAME set, the weight loss curve is downward - you know you're losing weight. Dynos are not really very much different in what they do so, if you're tuning and use the same dyno, and that same dyno shows power increases each time, then your power is going up.. really!

Here's me talking, never been to a dyno ever, not yet anyway cos I'm heading off to Crescent next week hopefully to see what the FCRs and Akra have done for my manhood!

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Post by burty » Wed May 09, 2007 4:58 pm

This is true of course, until someone gets a dyno run and says "I got 79bhp at the rear wheel, how does this compare with other TRXs".

It's all nonsense.

Can you imagine Yamaha selling their latest R1 and saying "Power is 180bhp, but ignore that because our Dyno is inaccurate, just accept that it's 20bhp more powerful than it was 6 months ago, Oh but we don't really know what 20bhp is either - it's more powerful than the GSXR1000, well we think so, but we don't really know"

Can you imagine going to the supermarket and buying 5 Tesco kg of spuds and it not being the same as 5 ASDA kg of spuds?

Or going to the petrol station and buying 18 litres of petrol and it not being the same volume as the 18 litres of petrol from the place down the road? If you said - excuse me I only get 5 miles to a litre of your fuel, would he say - "it doesn't matter so long as you always only get 5 miles to one of our litres"

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Post by Greg » Wed May 09, 2007 10:27 pm

I thought you were agreeing with me for a second there Burty!

What I was trying to say is that there is bound to be a percentage variance in the readings a dyno will give.. If on any given day Dyno A reads 5% more than Dyno B, then is the bike actually more powerful on A than it is on B - of course it's not! For argument's sake, imagine that the difference between the two is say 5%, so that A says 79hp and B therefore gives 75hp (ish) You do your first test on A then do your tuning and get a real 5% increase in power, but re-test on B .... the output readings will both be 79HP, and that is my point.

I know that the differences are probably likely to be smaller than 5%, but the reality is that to be credible, any kind of data-logging exercise be it BHP or mass must be done with the same equipment so that the interpretation of the data can likewise be consistent.

Now, as far as the potatoes are concerned, you should always get more than 5 kilos in a bag, if not, have a word with your local Trading Standards Office, and Asda's bags probably do contain more than Tesco's.. :lol:
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Post by burty » Wed May 09, 2007 10:42 pm

Greg wrote:I

For argument's sake, imagine that the difference between the two is say 5%, so that A says 79hp and B therefore gives 75hp (ish) You do your first test on A then do your tuning and get a real 5% increase in power, but re-test on B .... the output readings will both be 79HP, and that is my point.
Yes agreed, kind of. The output readings may be 79hp that's completely meaningless because it may be 79hp, 75hp or 84hp. But as none of these devices are calibrated to any standard, it may be 57hp or 97hp, or 790hp

rs1800

Post by rs1800 » Wed May 09, 2007 11:03 pm

There must be some standard somewhere? How do the manufactures calibrate them from new?

Although even if there was there will be wear and tear and they will change over time and I doubt many dynos get recalibrated (if there is such a thing? but I bet there is) so even if you take the bike back to the same dyno a year later it still might be 2 or 3 % different to how it was ?

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Post by Quan-Time » Thu May 10, 2007 9:47 am

1hp is a know figgure. from memory its the ability to lift 100pounds, 1foot of the ground in one second.. meaning, if i had a 10hp engine, hooked up a pulley to the rear wheel over a tree branch or something, rev'd it, and dumped the clutch, technically i should be able to drive forward and lift that 1000pounds in 1 second.. or something to this effect..

Same with a torque wrench.. its a leverage system thats translated into a roller system.

As for dyno VS dyno.. Yes they are out, but it should ONLY be very minimal. Unfortunatly in australia, cold nights and hot days means dynos CAN change during the day.. Anyone with webber carbies knows about this. Old holden (read "voxhaul" or whatever you brits have) had webber brand carbies, and they had a plastic diaphragm in them.. You needed to tune them for when you prefer to drive.. Basically hot / cold / dry / wet / etc.. they always went out of tune.. to the extent of your engine coughing and blowing smoke.

anyhoo.. most dynos are "self adjusting".. They have their own weather station (temp, humidity, bara-pressure, err.. one other i think) and adjust output figgures accordingly. So when its setup, it SHOULD be fine.. But many "older" ones are just "drive on roller, look at screen for number".. But anything within the past ~5years is auto self calibrating (so i read).

I have a flow bench.. I know what numbers my trx head flows, and how much it flows stock.. Sure i can tell you that in CFM, but i have NO idea how accurate my bench is.. Ive tried to calibrate it.. Its know what a 100mm (4inch) long tube of 25mm (1inch) diameter flows in CFM, same with 300mm (12inch) long 75mm (3inch) tube flows.. Flow'd both of those, to arrive at a "standard" so i guess my bench is "close" but will obviously be out by a bit.
Point is (as someone stated previously) 102.3hp might only roll 99hp on the SAME dyno at a different time of day, OR at same time of day, same conditions, just a different location.. long as you always use the same dyno, you will be set.

Also, correct me if im wrong here, but when dyno companies install dynos, they give like a 1week solid course on being a cert'd dyno operator or something ? like, trouble shooting, maintenance, correctly tying down a vehicle, all computer operations, etc.. if someone can confirm or deny this, please do !

and ffs, dont waste your money on letting your wife by more scales !! send her to the gym.. imagine how much money she has wasted
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Post by phuk72 » Thu May 10, 2007 9:56 am

There is a method of calibration for dynos but I have no idea how it works and most likley only calibrated dynos by that manufacturer so you will never be able to compare Dynojet with Fuchs for example.

There are so many variables it is frightening - roller bearings, wear on motor etc on the dyno and tyre pressure, chain condition etc on bike you can never compare.

Dynos do vary by more than 5% - as I mentioned earlier, at one of these free dyno runs at a show my bike was allegedely making more power at the wheel that it had done a month or so before at the crank.

Think of a dyno as a way of smoothing out the power curve and, despite my starting a bragging thread :D about how much power my bike makes, a way of showing improvements based on work done.
Nothing more.
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Post by HansJ » Thu May 10, 2007 9:57 am

and don't forget that people are pleased when seeing high figures, or that the improvements have turned out good. My mechanic showed me on my bike the difference between a normally lubed fresh chain, and what difference it made to lube the chain, we gained almost 3 BHP, and the chain was not dry before...
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