FOAM PODS
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h2bchris
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Yogi is right , it is best to keep std air box on torque and smoother running etc , but in the case when having big carbs , like i runs 34 mm's,on my h2 , the std air filter rubber won't fit, so thats why i have fitted pods, sorry for the confusion !yogi20 wrote:If you have the standard air filter keep it on
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666rog
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Tea strainer type filters are just about the most restrictive thing around. But dont take my word for it folks. get one, take it apart and push all the vertical stands together and all the horizontal strands together. Compare blocked area to that of the bellmouth and i think you will be shocked at the lost intake area.
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TWO SMOKE SMUT
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Ill second that , race foams are the only thing I'd do...
But as mentioned further above I think in actual fact, the standard air box might be better for me ill just put up with taking the rubber on and off... Does it piss anyone else off??
And I don't want big carbs or anything like that so
But as mentioned further above I think in actual fact, the standard air box might be better for me ill just put up with taking the rubber on and off... Does it piss anyone else off??
And I don't want big carbs or anything like that so
.........SMELLY BLUE NOISE..........
- scouse
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Mitsui Spy wrote:Okay, I'm clearly off the mark here. So help me out.
Take Rog's measurements:
59 - 47 = 12Hp
12/59 * 100 = 20% loss (wow!).
12 Hp = 9kW lost mainly as heat at full power.
Some will be lost to the transmission oil and through the casings, the rest lost in the drive chain, tyre, wheel bearings, tyre. Also I expect the spinning wheel may lose some energy in disturbing the air. Owt else?
Okay if Gary and Rog & Smut say that these are the losses then I've got to respect that. In which case it's interesting how the heat is lost. Imagine having a 3kW immersion heater fitted in your gearbox - it wouldn't be long before it was smoking. There's a limit to how much heat can be lost from the gearbox oil, especially when it's also receiving conducted heat from the cylinders.
Tyres can get quite hot and have a fairly large surface area so I expect they can dissipate a couple of kW.
Does the chain really dissipate 5kW of heat? That would make it about 88% efficient on the 500 - 88% is terrible! Chain drives are usually quoted at 95 - 98% efficient.
Of course, other than racing engines, most engines operate at much below their full power most of the time so the losses are much less. Perhaps the airflow around a motorcycle carries more of the heat away than I imagine. Interesting though innit? No? Just me then.
All said, I know it is a benefit (done it myself), I just can't get my head round the figures. I must be missing something (a life before anyone else says it).
And someone help Smut out with his pods to stop me waffling on.
Sorry Neil I'd already written this before your last advisory.
you forgot about this little guy .. μ I think its responsible for most of the loss, however if you were to fit ceramic bearings to the crank, gearbox, rear wheel, then you will reduce it's overall effects, it's the main reason why a smaller chain works as I am sure you know with a smaller chain there is less contact area overall, so less friction
Gary T
Boffin in a coffin
- Mitsui Spy
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That's not even a real letter!scouse wrote: you forgot about this little guy .. μ
Gary T
A recent Mori poll asked 100 people exactly how full of shite they thought Mitsui Spy was. 68% said he spoke "total bollocks", 21% said his views were "complete and utter knackers", 18% said "He's irretrievably stupid", 2% said "That c*nt needs ethnically cleansing" and 3% said "I don't like ice cream"
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Hal
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TWO SMOKE SMUT
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PRINCIPLE POINT!!!!!Hal wrote:Another big reason that racers change to a narrower chain is because it weighs substantially less. The less it weighs the easier it is to accelerate it. That is, more power is transmitted to the wheel and tyre since it isn't lost trying to make the heavier chain actually rotate faster.
.........SMELLY BLUE NOISE..........
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Neil the Don
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Finally !
Yeah stick with an airbox !
Although there are Chinese versions of the unifilters, which also stay on , and flow very well. But they`re about £18 a piece. Fine on race bikes, should filter air well , probably better breathing than an oem airbox .
But as you have an airbox , and don`t want a performance gain, real or imaginary ; Yeah, use the box and quite being lazy with the inlet rubber !!
( Unless it`s a replica inlet rubber. Which I find shrink with fuel blow-back and creep off the carbs. )
And how about building some stocks for the MFN rally, so we can all throw tomatoes at M.S ?
Yeah stick with an airbox !
Although there are Chinese versions of the unifilters, which also stay on , and flow very well. But they`re about £18 a piece. Fine on race bikes, should filter air well , probably better breathing than an oem airbox .
But as you have an airbox , and don`t want a performance gain, real or imaginary ; Yeah, use the box and quite being lazy with the inlet rubber !!
( Unless it`s a replica inlet rubber. Which I find shrink with fuel blow-back and creep off the carbs. )
And how about building some stocks for the MFN rally, so we can all throw tomatoes at M.S ?
- Mitsui Spy
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Hal wrote:Another big reason that racers change to a narrower chain is because it weighs substantially less. The less it weighs the easier it is to accelerate it. That is, more power is transmitted to the wheel and tyre since it isn't lost trying to make the heavier chain actually rotate faster.
TWO SMOKE SMUT wrote: PRINCIPLE POINT!!!!!
Thank you. Now we may be getting somewhere.Neil The Don wrote: Finally!
So that's 3 that agree that inertial resistance is the principle point....and the important point of inertial resistance is that it DOESN'T LOSE POWER. It stores it as kinetic energy. No heating effect. Inertial effects play havoc with dyno readings - inherent on an inertia dyno of course - but even on a braked dyno unless a steady state is maintained at each rev point.
Okay, so I'm playing devil's advocate here and the upshot is the same. There's less 'available' power with the larger heavier chain (and I've never said that there's no frictional loss). You could even argue that the power is indeed lost, as the energy stored in the chain and sprockets is more likely to be scrubbed off by the brakes than put back into propulsion.
BTW on Wednesday I'm going to Newcastle to conduct the installation of a dyno on a 3" output shaft from a 600Hp Cummins. It will supply 'live' data in real operational conditions. We do a similar thing to to individual gear teeth on the primary reduction cogs in Her Majesty's submarines so that they can measure the root stress in the teeth while the sub is in service. One day I'll do the same to a bike.
I'll bring the tomatoes - the tomatoes will be on me you might say.
Now then, how about some politics and religion?
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Neil the Don
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- Mitsui Spy
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TWO SMOKE SMUT
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- Mitsui Spy
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