crank bhp to rwhp losses

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hobot said:
Dances with Shrapnel said:
A 1000 hp scenario would require substantially heavier chains and gear and the loading (and likely speed of components) would be significantly greater. It scales up.
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OH alright Dancer I will put out the light in the old lamp I pulled out the lake and reduce hp to only twice as much say 200 but sticking to my story > there is essentially same drive line drag factor regardless of the power turning it till distorting like you say,
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Drag factor (as you call it) is more or less linear so close to a fixed percentage; generally double the load then double the power and power loss. Double the speed and generally double the power loss. Fixed percentage is close enough. Some losses due to churning of lubricants in a gear box and seals are probably torque independent for a given gear box. By the way, nobody mentioned distortion at 200 hp, only greater tension and loading. I may as well remind you that we are posting on the Norton Commando Motorcycles forum; at 200 hp we are talking about something substantially different from an AMC gear box and skinny tires. I think this is where you are getting confused. Remember what I mentioned up above about scaling up.

hobot said:
Chain friction pin on plate will some what increase but there is just not much surface translation speed in the links, especially the loaded ones so what would matter more if over powered would be shaft bending binding in bearing supports.
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Look up coefficient of friction. It is linear. Double the tension and you double the link bending force. Really fundamental stuff here hobot. Furthermore, surface translation speed will double if you double the speed and typically speed and load increases are associated with an increase in power.

hobot said:
If Kevin was reporting race bikes of similar class power plants then its valid to speak of percentage loss per item as hp will all be similar but put a Norton on same dyno and fat tire will skew computing real shaft power.
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You will have to take this up with Kevin Cameron. :lol: I believe the reference is available online for your edification.

hobot said:
Anyway please never say you learned your current power transmission concepts form hobot.
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Absolutely! Excellent advice! :D

hobot said:
http://forums.tdiclub.com/showthread.php?t=75062
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This is a reference? Plenty of contradictions in there. Do you believe everything you read on the internet?

If you want to understand chain drive systems look up a paper from Bristol University Dept. of Mechanical Engineering in the UK titled: Optimisation of the chain drive system in sports motorcycles.
 
Aw shoot - our chains are so efficient they do not increase their friction to hardly measure till they distort or pulled apart. I tried to set ya straighter on mechanical drive factors to save you embarrassment if speaking with with real power transmission experts but resisted, so continue to use your sliding scale of blurry percentages on Nortons and I will use data based 4.5 hp set fudge factor as maximum power-rpm drag factor for my 45 hp Combat or 100+ hp next Peel. So my snide humor guip *how does it know* was aimed directly at your mis conception on mechanical drag, not mine. This does overlap with rocket science drag for a mass reaching escape velocity through atmosphere. Please do not get mad at me on this as I am here for fun and information and glad you have set me straighter on other things I did not understand as well. We should try to contact Kevin and ask him to explain his remarks better.
 
hobot said:
Aw shoot - our chains are so efficient they do not increase their friction to hardly measure till they distort or pulled apart.
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That is funny. For chain drives, friction is, in part, a function of load.

And you assert 4.5 hp loss at 100 hp?

That would require about, ....................drum roll please...

99% efficiency for primary chain
99% efficiency for gear box
99% efficiency for rear drive chain, and
98.5% efficiency for rolling resistance.

That's silly. :lol: and fictional.

Read the references I cited and more, not the online opinions in some forum. :lol:
 
I am not confused by both ways of talking about or measuring drive train component percentage of drag. One way is how much each component contributes to total drag and 2nd way is how much percent they steal from total shaft power. Being nasty when your confusion pointed out is rohan typical, so carry on thinking-exclaiming its me misleading others on power train and chain dynamics.
 
You appear to have no comprehension of humour, Steve !!!!
OR the confusion you are (sometimes)/(constantly) spreading. ?
You and several others.

Most science is quite scientific these days.
And established on VERY established principles.

If folks followed all your advice/technical points to the letter, where would this forum be. ?
Laughable, in many cases, we thinkz

This is nothing but pointing out the bleedin obvious.
??

What % of accurate posts do you consider you have posted here.
100 %
99.9%
99.8%

or less ?
 
And just how seriously to you expect us to take EVERYTHING you post,
when you show pics of things like your lawnmower engine shot full of 45 cal holes.

I can recall when you were on this forum before it was this forum,
and you seemed a young buck keen to learn about all things Norton.
Back then you were called Steve.
But those days seem long gone, very long gone....

You either need to be serious, or be the village idiot.
But can't be both ... ?

You might also think about the quality versus quantity aspect.... ?
 
I sure don't mind Steve's Bonny and Clyde lawnmower photos or whatever. Live and let live.

I also doubt very much that a simple percentage figure actually fits for power loss, there are too many variables. It is highly unlikely that the same drive line with increasingly large amounts of horsepower transmitted would graph power loss in a straight line. Nor would it show exactly the same overall horsepower loss when transmitting 100 hp instead of ten.
A percentage figure gets one in the ballpark.
 
worntorn said:
I sure don't mind Steve's Bonny and Clyde lawnmower photos or whatever. Live and let live.

I also doubt very much that a simple percentage figure actually fits for power loss, there are too many variables. It is highly unlikely that the same drive line with increasingly large amounts of horsepower transmitted would graph power loss in a straight line. Nor would it show exactly the same overall horsepower loss when transmitting 100 hp instead of ten.
A percentage figure gets one in the ballpark.
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In the ball park, exactly. When you read literature that cites 2-3% loss per component for example and you propagate that through a drive system you obviously get some variance; it is simple math. Even a difference in gear box lubricant or amount of lubricant will make a difference. I think there is enough credible information and test data referenced in this thread to support the percentage estimate for a Commando. Keep in mind where this thread started with the original post. Obviously if one were to run a Commando with bone dry chain their results would be a greater percent power loss than from someone who properly maintained their chain....but here I go again.
 
worntorn said:
I sure don't mind Steve's Bonny and Clyde lawnmower photos or whatever. Live and let live.
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Indeed, I enjoyed a good chuckle now and then too.
But if someone can dish out the (sometimes black) humour, they have to expect to get some back ?

And if some posts need to be signed serious steve or hobot the hillbilly to distinguish them apart,
in amongst some mumbo jumbo at times, then what hope have newbies got of learning from stuff here ??
I'd also comment that everyone makes a boo boo now and then (even LAB !),
but chronic dud postings are not a good look for this forum ?
 
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