Crank shaft HP

Or stirring up old anamosities . :mrgreen:

Bernhard said:

Can I bring your attention to the following from;

http://www.factorypro.com/dyno/true1.html

Note the percentage loss from the various sum of parts; tyre loss, valve train loss e.t.c.


Aprilia, RSV4
999.6cc, 2010
Tested by Micah Shoemaker's AF1
2009 #1 USA Aprilia dealer

140.2 True HP


note: claimed crank HP = 180
Take crank hp, subtract 15% from reported reading, take that and subtract 10% for tire losses and 3% to 5% for drive train losses and add 4-5 for the slipon and you come up with about 140 True. Perfect

With all the dynos giving different reading from different parts of the globe, it’s no wonder that it becomes very confusing to an onlooker :!:

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So you're saying to multiply crank HP by 78% to get Rear wheel HP correct?

Anyone else agree with this?
Jim S

Jim take in closely the figures dang ole John Magnar posted going with the more realistic higher range of efficiencies of each component for most realistic estimate of shaft hp, which implies about 5 hp max in our drive trains and 5 more in heavy loaded tire. As dyno bragging rights are peak power, implies add 10 hp to rwhp for Norton type engines. You can see the funny results when trying to use a percentage of loss instead of fixed hp constant, from one engine to the next even on same drive train. Can't envision anyone with a clapped out drive train full of crap and binding alignments spending on a dyno run to have to use the lower efficiencies possible in a drive train, so can ignore that unreasonable hi power cost. 100 rwhp Norton ain't putting out 120 crank hp much as I'd like it too.

One hp = ~745 watts/min so 10 hp drag would mean 7450 watts of heat to dissipate. That's like 74.5 100 watt incandescent light bulbs of heat developed.
5 hp tranny drag implies ~37 bulbs worth of heat inside AMC type gearbox, I don't think so below 200 mph.

hobot said:

One hp = ~745 watts/min so 10 hp drag would mean 7450 watts of heat to dissipate. That's like 74.5 100 watt incandescent light bulbs of heat developed. 5 hp tranny drag implies ~37 bulbs worth of heat inside AMC type gearbox, I don't think so below 200 mph.

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Went through that same mental excercise and figure it's in the ball park. Feel a rear tire off of a vintage race bike after only a few laps on Daytona; other than land speed attempts, that's the closest one will come to WOT at peak power. Gear box is aluminum and can easily shed heat and chains flaping in the breeze are easy to cool.

In fact, P.Williams was quoted - remarking on P.Read`s being more gentle on machinery than him, not breaking gearbox mainshafts & etc, whereas D.Croxford - he was a bit on the rough & ready side...

Daytona is out of sight for me Dances, love it you can share a bit of the sensations. Pilot sense makes or breaks parts or records if taking care of tires too. I can heat up road tires in public too hot to leave a hand on but street tires don't melt and glob and gosh up like race compound. In the end heat in tires and engine will limit how long Peel can press ahead as intended. I travel as fast as ever on THE Grit in cars or bikes but last few years my lines and forces style changed so tires wear is way lower. I've recently learned that nitrogen helps cool tires alot by avoiding the ambient water vapor in plain air. I intend to mount a remote temp reader aimed at rear tire and also sheet of foam to measure tire swelling at high speed. I will run thin ATF which can carry off more heat than thicker lube but don't think tranny temps will be an issue,though Peels got about as hot as the engine cases at times. Mostly felt it was just conduction through alloy cradle as race like runs lasted 20-40 min. I've pressed enough on fat race tires to have a bad opinion of them on edges and no longer fear those wearing them knowing what they got to deal with compared to skinny ones I securely ski on just removing enough to carry off most the heat with it but not the grip.

Back on point, I think the drive train drag physics covered enough to realize its a constant per rpm not % of power applied and 10 hp is pretty reasonable upper zone of our drives to add back to rwhp. I realize to drive a dyno harder will develop more heat in drive train but that's not necessary costing more drag but maybe less as oil thins and spinning parts get looser.

J.A.W. said:

In fact, P.Williams was quoted - remarking on P.Read`s being more gentle on machinery than him, not breaking gearbox mainshafts & etc, whereas D.Croxford - he was a bit on the rough & ready side...

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Having met all three of these guys at some point and having watched them race more than once, I note Read for smoothness, Williams for determination and Croxford for brave, which actually means 'where is it going to happen?', and most of the time it did, hence his 'notches on a stick' method of 'departure' recording :roll:

Great guy and fun to watch though....right in front of us exiting Gerrards at the Mallory Post TT...that was the year the medics took of his boot to find he still had his toe nails painted pink from party high jinks on the Island....

hobot said:

Daytona is out of sight for me Dances, love it you can share a bit of the sensations. Pilot sense makes or breaks parts or records if taking care of tires too. I can heat up road tires in public too hot to leave a hand on but street tires don't melt and glob and gosh up like race compound. In the end heat in tires and engine will limit how long Peel can press ahead as intended. I travel as fast as ever on THE Grit in cars or bikes but last few years my lines and forces style changed so tires wear is way lower. I've recently learned that nitrogen helps cool tires alot by avoiding the ambient water vapor in plain air. I intend to mount a remote temp reader aimed at rear tire and also sheet of foam to measure tire swelling at high speed. I will run thin ATF which can carry off more heat than thicker lube but don't think tranny temps will be an issue,though Peels got about as hot as the engine cases at times. Mostly felt it was just conduction through alloy cradle as race like runs lasted 20-40 min. I've pressed enough on fat race tires to have a bad opinion of them on edges and no longer fear those wearing them knowing what they got to deal with compared to skinny ones I securely ski on just removing enough to carry off most the heat with it but not the grip.

Back on point, I think the drive train drag physics covered enough to realize its a constant per rpm not % of power applied and 10 hp is pretty reasonable upper zone of our drives to add back to rwhp. I realize to drive a dyno harder will develop more heat in drive train but that's not necessary costing more drag but maybe less as oil thins and spinning parts get looser.

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I thought dry Nitrogen in tires was primarily used for pressure stability and did little to nothing for cooling - other than preventing one from starting with under inflated tires to get them up to pressure.

ATF in the gear box will likely reduce fluid drag but probably at the expense of longevity. Report back to us if you ever get it on the road long enough to tell.

Not sure if ATF's heat shedding ability is much different than most any other hyrdocarbon based lubricating oil.

The heat you are experiencing at the gear box is probably mostly due to convection & radiant heat transfer from engine.

Drive train loss is a % of power (ie load and speed) but in the realm of what we are talking about (a Norton drive train with 50 to 70 crankshaft HP with the torque & rpm characteristics of a Norton twin) and measuring off of a rolling road dyno at peak torque or peak power, 10HP loss for the drive train and rear wheel is a reasonable estimate.

1. I too thought N2 was just for more stable PSI as temps changed but was set straighter that tires also run cooler d/t lack of water vapor holding the heat in. That's a lot to be said about water in gaseous state absorbing heat to re-radiate it. i have not searched this up but will to see if its as significant as the tire guy lead me to believe, inbetween telling me about some hot rod car antics with police chases like Dukes of Hazard so indeed understood tire heat traction handling extremes.

2. I have burnt up Peels sleeve gear bushes on thick synthetic gear lube and saw that that area goes completely dry at hi rpm then fills seam with ceramic like grit. Engineer that build oil filled radiators of various equipment like transformers or heat exchangers verified thinner oil absorbs and conducts and conveys more heat than thicker oil. I only care about the heat in bush interfaces and will have ATF inside when shooting for a record or long distance cruising. The Manx guys found same thing, staying in power band zone a long time in lower gears while dicing sweepers and chicanes. I am not the first to test this out ok and asked before hand to don't claim credit just 2nd the advice. I did not do it for less drag just less destruction and it indeed did for couple of season exploring WTF Peel was capable of. I agree most trany over all temp was from engine via thick alloy cradle. Don't think radiant heat is significant transfer to gear box.

3. I will no longer look at drive train loss as a percentage, even though percentage efficiency of each component is needed to come up with its drag factor to add to the others. Fixed Percent of drive train loss only makes sense if constantly referring to the same engine being tested each time. Make this engine more powerful and the drive train loss % goes down as power goes up.

4. We both came dang close to maximum gearbox/primary loss, 4-6 hp, which I now think might be closer to 4 with ATF inside. I don't remember what size tire the drag figures were derived from but my sense right now is for some fat balloon tire not ice skate like Brit sizes. So i'm thinking maybe only 8 hp lost up to say 100 mph.

hobot said:

1. I too thought N2 was just for more stable PSI as temps changed but was set straighter that tires also run cooler d/t lack of water vapor holding the heat in. That's a lot to be said about water in gaseous state absorbing heat to re-radiate it. i have not searched this up but will to see if its as significant as the tire guy lead me to believe, inbetween telling me about some hot rod car antics with police chases like Dukes of Hazard so indeed understood tire heat traction handling extremes.

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Search it, check it out and report back. I think you will find the bit about water vapor absorbing heat to re-radiate it is more like the water vapor is jazzing the tire pressure, nothing more, nothing less.

hobot said:

2. I have burnt up Peels sleeve gear bushes on thick synthetic gear lube and saw that that area goes completely dry at hi rpm then fills seam with ceramic like grit. Engineer that build oil filled radiators of various equipment like transformers or heat exchangers verified thinner oil absorbs and conducts and conveys more heat than thicker oil. I only care about the heat in bush interfaces and will have ATF inside when shooting for a record or long distance cruising. The Manx guys found same thing, staying in power band zone a long time in lower gears while dicing sweepers and chicanes. I am not the first to test this out ok and asked before hand to don't claim credit just 2nd the advice. I did not do it for less drag just less destruction and it indeed did for couple of season exploring WTF Peel was capable of. I agree most trany over all temp was from engine via thick alloy cradle. Don't think radiant heat is significant transfer to gear box.

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Viscosity has squat to do with conduction of heat other than physical transport and/or pumping losses. Transformers use transformer oil for cooling yes but also for insulation. Transformer oil has significantly poorer thermal conductivity properties than engine oil and castor oil so this flies in the face of what you are stating here. Have a look at the following link.

http://www.engineeringtoolbox.com/thermal-conductivity-liquids-d_1260.html

I would say radiant heat is a significant source of heat from the engine to the gear box. Do a set run and carefully measure the rise in your gear box oil, wrap your gear box in tin foil and do the set run again and carefully measure your gear oil temp rise and report your findings to us, oh, and don't get pulled over and have to explain yourself with the tinfoil.

hobot said:

3. I will no longer look at drive train loss as a percentage, even though percentage efficiency of each component is needed to come up with its drag factor to add to the others. Fixed Percent of drive train loss only makes sense if constantly referring to the same engine being tested each time. Make this engine more powerful and the drive train loss % goes down as power goes up.

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I think you have this percentage thing all garbled up but that's ok.

oh, and don't get pulled over and have to explain yourself with the tinfoil.

I can't find anything on N2 helping heat, just lack of moisture so dry air might do as well being 78% N2. I don't know and mentioned heat help from N2 in case someone had a clue. To many things to interfere with steady consistency tire heat tests in public for me.

Viscosity has squat to do with conduction of heat other than physical transport and/or pumping losses. Transformers use transformer oil for cooling yes but also for insulation. Transformer oil has significantly poorer thermal conductivity properties than engine oil and castor oil so this flies in the face of what you are stating here. Have a look at the following link.

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Oh yes it does. Your site is interesting but only covers different substances not oil viscosity heat carrying. Transformer oil like in our Lucas coils has to be electrically non conductive too.

http://www.dsifluids.com/OptiCool%20tec ... 0paper.PDF
Heat Transfer Effectiveness:
OptiCool Fluid cools electrical equipment better than conventional transformer oil. This is because OptiCool has much lower viscosity (it’s “thinner”) than similar petroleum products. The single most important factor in determining the heat transfer characteristics of a homologous series of hydrocarbon fluids is the viscosity.

I would say radiant heat is a significant source of heat from the engine to the gear box. Do a set run and carefully measure the rise in your gear box oil, wrap your gear box in tin foil and do the set run again and carefully measure your gear oil temp rise and report your findings to us, oh, and don't get pulled over and have to explain yourself with the tinfoil.

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I don't think so nor intend to waste good hat foil on dirty gearbox but simpler way would just place a thermometer insulated well on gear box side and placed on black surface facing engine then run with and w/o a light shield it front of it. I've explained my foil hats before but few not my severe brain and spine inflamed states understood, nor wish that on anyone else to understand. Btw it takes at least two layers but won't filter out the mind control mm size waves just the ambient EMF that inflames more.

Sorry hobot, you are all wet on the above but believe what you want to believe. OptiCool claims to be better than conventional transformer oil for heat transfer which is p*ss poor for heat transfer when compared to castor oil or motor oil.

But then again maybe you should be running OptiCool transformer oil in your gear box and report back to us on your results. :roll:

Duh Dances, the transformer oil site stated the fact thin oil carries more heat off than thicker oil, if you think its just a sale pitch, oh well don't believe it then as likely not an issue with your tranny anyway.

hobot said:

Duh Dances, the transformer oil site stated the fact thin oil carries more heat off than thicker oil, if you think its just a sale pitch, oh well don't believe it then as likely not an issue with your tranny anyway.

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Duh hobot, it's called convection. So if you want your gear box to cool off faster when the ignition is off and it is just sitting there then have at it.

Sorry Dance's convection its not the same thing as heat absorbing and carrying off capacity and is not a factor in the bush spaces I'm concerned with. The live folks I checked with were using pumped oil heat exchangers not passive convection like my old tractor engine, which indeed better be water and not thick oil or even thin oil as oil just don't have waters high heat absorbing/carrying capacity. It not the over all heat of the tranny or engine I'm concerned with, oil can't help that to matter, its the super high heat in close spaces shearing the fluids and filling back in.

hobot said:

Sorry Dance's convection its not the same thing as heat absorbing and carrying off capacity and is not a factor in the bush spaces I'm concerned with. The live folks I checked with were using pumped oil heat exchangers not passive convection like my old tractor engine, which indeed better be water and not thick oil or even thin oil as oil just don't have waters high heat absorbing/carrying capacity. It not the over all heat of the tranny or engine I'm concerned with, oil can't help that to matter, its the super high heat in close spaces shearing the fluids and filling back in.

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So oil "flow" for lubrication is your problem, not heat transfer.

Other than in convection only applications, it is down right silly to say lower viscosity for "better" heat transfer. If you have a convection challenge on your bike (like ignition coils) then yes, lower viscosity makes sense if it is critical.

Look at the chart I referenced above as a simple example comparisons of various fluids heat shedding (transmisivity) capabilities. It should become clear to most what we are discussing and the context.

For whatever reason, you apparently think you have a lubrication problem in your sleeve bearing, not a heat transfer problem. Fix the lubrication probelm and heat is not an issue.

From what I can tell, you have things so horribly garbled up here.

Too bad we cannot check your "live folks" references.

hobot said:

Engineer that build oil filled radiators of various equipment like transformers or heat exchangers verified thinner oil absorbs and conducts and conveys more heat than thicker oil.

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Again, look at the fluid properties and tell me again how a transformer oil will conduct more heat. Transformer oil has 75% the thermal conductivity of engine oil and 60% of the thermal conductivty as that of castor oil. The transformer requires convection flow. Why does Kerosene (as most everyone knows it's as thin as water) have the same thermal conductivity as engine oil and not transformer oil.

I will speculate here that the "other" property of transformer oil (dialectric strength) probably has something to do with not having as "good" a thermal conductivy as engine oil.

It's the convection and resultant flow that requires the lower viscosity; or at least enhances heat transfer but most all of this could be done buy pumping. Your engineer reference could be correct if "conducts" more heat is in the context of better convection.

You have this well garbled up.

Peel sleeve bushes ran out of oil, then heated to ceramic grit. So yes by far the main reason I'd checked into ATF was better flow. ATF being thinner than gear lube and there by better heat transfer * so no its just a side note minor frosting on the cake. Fairly soon will see if can rifle drill into cogs so their spin tends to force fluid inside rather than out. This is still sort of left over reflex reaction to past Peel stock gear ratios dicing it up in narrows against balloon tires in and out of red zone in lower gears. Next Peel may be able to just stay in 4th. OUr Manx racer here Steve Manning said same thing happened to him staying in hi rpm in lower gears.

I've seen heat capacity charts before and had to use em in school, too bad liquid water can't take hi heat and rusts stuff or about best there is for lube and heat flow. I did not mean to imply transformer oil was better heat carrier than engine oil, just that what ever oil type used the thinner the better if just for heat transfer. Engine and gear lubes don't have to be such good dielectrics so different substances than coil winding oil. What ever fluid, by being thinner can flow or pump easier faster and bubble up more by convection.

Any who I like the look of Dextron finished bushes better than the gear lube now so put what ever in yours is all. I'm using up old lube in Trixie but no way do I press her for long in low gears.

Well gald to see the hobot has come to my senses.

I may have mentioned somewhere in access Norton about water being used in the not to distant past as the lubrication for main bearings on large grinding mills used in mine/mill applications. Bearings were made of wood (later mycarta) blocking on end where the end grain of the wood formed the bearing surface. The water pressure was initially jacked up to float the mill but once under rotation the pressure was reduced. The best of cooling and hydrodynamic wedge all in one. So water for lubrication is not far fetched. Used in modern water pumps all the time, the main reason for a lantern ring on a shaft pump shaft.

As for the Norton sleeve bearing there are at least two types (and probably more) that I am aware of; the earlier Commando and Mk3 Commando. I do not recall the particulars. In your case it sounds like a complete starvation and then heat and then all is lost. Seems like some sort of scrolling and maybe relief drilling would help, then again it may make a mess and too much oil would then pass and leave an unsightly puddle on the garage floor.............uhhhh.....never mind.

Its the Conductivity that counts :? as in Glycol / radiator anti freeze is MORE conductive than water . Unfortuately glycol can burn . Cooling oil , Hobot .

Why dont the skinflints throw needle rollers in the Sleeve Gear , and a few other laces in the Trans . Just Needles the Dia. of the Bush thickness .
With end keeper rings . Knock em up in a few enenings .