Engine regulations

Flatlander
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Flatlander
Edited Date/Time 1/26/2012 5:09am
To help reduce cost and give a much more equal engine performance does it make sense to look at these type of engine regulations?


Maximum RPM (mandatory limiter, this would increase engine life and minimize engine development costs)


Maximum compression ratio limit (say 13: to 1)


Maximum Valve lift (say 12mm)


Maximum Throttle size (restrictor)


Minimum piston,crank & con-rod weight




Would this be a good or bad thing for MX?

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72kiteboarder
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72kiteboarder 7/23/2009 7:56am
7/23/2009 7:56am
Stock Engines only.
OW38B
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OW38B 7/23/2009 9:29am
7/23/2009 9:29am
These are cheap to run and easy to maintain.

Just let them run in the 250cc class and your problem is solved...........

breck
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breck 7/23/2009 9:39am
7/23/2009 9:39am
restrictor plate races!

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tommycroftsbarber 7/23/2009 9:54am
7/23/2009 9:54am
Revenge of the Nerds tricycle races - one lap, chug a beer..
xnationalwrench 7/23/2009 10:55am
7/23/2009 10:55am
Stock engines are ok but if you have watched a NMA race the wars that come out of the stock class are amazing they put WWE to shame
breck
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breck 7/23/2009 10:58am
7/23/2009 10:58am
No one in the stock class is running a stock motor...

Supply the motors an hour before practice?
Sledneck
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Sledneck 7/23/2009 11:36am
7/23/2009 11:36am Edited Date/Time 7/23/2009 11:37am
FIM=2 strokes=Good

jtomasik
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jtomasik 7/23/2009 11:38am
7/23/2009 11:38am
Sledneck wrote:
FIM=2 strokes=Good

Maybe it's an attempt of getting manufacturing back to Europe. KTM is probably loving the rule changes.
hillbilly
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hillbilly 7/23/2009 12:24pm
7/23/2009 12:24pm
WTF?

why do we need regs?

cut out an entire cottage industry of engine builders?

You think that HP is what gets riders hurt?

You think engines are the largest exspense?

Get rid of the FIM and the AMA,try that
ASH510
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ASH510 7/23/2009 12:38pm
7/23/2009 12:38pm
i think it could be good.
but it could also stop development altogether.
but 99.5% of all who have ever rode a dirty bike
can not run it at more than 90% or so of what it
is able to do. straight line drags do not count.

brakkeman_ 7/23/2009 12:51pm
7/23/2009 12:51pm
whats next, adding weight when you win?
tracks with only left hand turns?
cpj36
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cpj36 7/23/2009 1:14pm
7/23/2009 1:14pm
brakkeman_ wrote:
whats next, adding weight when you win?
tracks with only left hand turns?
Nascar tried that back when they couldn't get a decent TV package, had empty seats in the stands and the same guy winning every week. They also had free radio broadcast, since it wasn't on TV.

Wonder how it turned out?
cpj36
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cpj36 7/23/2009 1:28pm
7/23/2009 1:28pm
OW38B wrote:
These are cheap to run and easy to maintain. Just let them run in the 250cc class and your problem is solved........... [IMG]http://i68.photobucket.com/albums/i37/ow38b/313994-RCmotor.jpg[/IMG]
These are cheap to run and easy to maintain.

Just let them run in the 250cc class and your problem is solved...........

Amazing, every area of concern can be addressed by the 2 stk. Less rpm, compression, no valves, no need for restrictor and no need to keep JGR from machining exotic engine components.

Unfortunately that solution is too expensive, it seems it's much cheaper to keep the 250f's and build 350's with EFI , maybe add traction control next and some fancy ignitions.
Jabjr222
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Jabjr222 7/23/2009 1:50pm
7/23/2009 1:50pm
I think in moto you should do whatever you want to the engines... Let the manufacturers figure out the base and let the engine builders do the rest.

In moto, it really is all about the rider. Mostly.
lostboy819 7/23/2009 3:06pm
7/23/2009 3:06pm Edited Date/Time 7/23/2009 3:07pm
Flatlander wrote:
To help reduce cost and give a much more equal engine performance does it make sense to look at these type of engine regulations? Maximum RPM...
To help reduce cost and give a much more equal engine performance does it make sense to look at these type of engine regulations?


Maximum RPM (mandatory limiter, this would increase engine life and minimize engine development costs)


Maximum compression ratio limit (say 13: to 1)


Maximum Valve lift (say 12mm)


Maximum Throttle size (restrictor)


Minimum piston,crank & con-rod weight




Would this be a good or bad thing for MX?

You can make all the rules about performance that you want but the great thing about MX is that its 90% rider and 10% bike. The same guys will win even if you put them all on stock bikes. A factory bike may gain some one a few positions but you can take an average rider and put him on a great bike but he will still be average. Now a great rider on a great bike is something to see and that is why they make the big money.
Ing
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Ing 7/23/2009 3:42pm
7/23/2009 3:42pm
What is the problem now?

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BobbyM
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BobbyM 7/23/2009 3:47pm
7/23/2009 3:47pm
make everybody race with a leg cutoff...that'll even up the field
Jabjr222
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Jabjr222 7/23/2009 4:41pm
7/23/2009 4:41pm
BobbyM wrote:
make everybody race with a leg cutoff...that'll even up the field
If you want to even the field, cut both legs off... one leg and nothing will be even!
brakkeman_ 7/23/2009 4:45pm
7/23/2009 4:45pm
Some of the stuff the factory riders are running now will be on future bikes, works bikes are good for the development of the bikes.
BobbyM
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BobbyM 7/23/2009 4:52pm
7/23/2009 4:52pm
BobbyM wrote:
make everybody race with a leg cutoff...that'll even up the field
Jabjr222 wrote:
If you want to even the field, cut both legs off... one leg and nothing will be even!
left leg for counter clockwise tracks right legs for....lol
project racer 7/23/2009 5:08pm
7/23/2009 5:08pm
A modified engine has the ability to make better power throughout the range, verses a stocker that has to have the dog snot run out of it to get even close to what the mod engine produces.

If you have a 250F that makes 43HP at 10,000 rpm verses a stocker making 36-38HP at 12,000 rpm, the reliability of the stock engine is greatly reduced. The mod engine is working less to produce more.
cpj36
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cpj36 7/23/2009 5:40pm
7/23/2009 5:40pm
The perception is that 450's are so fast pros are detuning and there's not much difference. Why would they spend 30K on forks if it didn't matter much? In the 250 class where they can use all of the bike it's a huge advantage

Maybe they've changed drastically during the couple years since he said this but KW compared it to running a showroom car at Daytona.
Ing
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Ing 7/23/2009 7:12pm
7/23/2009 7:12pm
project racer wrote:
A modified engine has the ability to make better power throughout the range, verses a stocker that has to have the dog snot run out of...
A modified engine has the ability to make better power throughout the range, verses a stocker that has to have the dog snot run out of it to get even close to what the mod engine produces.

If you have a 250F that makes 43HP at 10,000 rpm verses a stocker making 36-38HP at 12,000 rpm, the reliability of the stock engine is greatly reduced. The mod engine is working less to produce more.
Sorry project racer but the inverse is actually true. Same displacement with more HP = less longevity. Just a fact.
CamP
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CamP 7/23/2009 7:21pm
7/23/2009 7:21pm Edited Date/Time 4/17/2016 1:05am
project racer wrote:
A modified engine has the ability to make better power throughout the range, verses a stocker that has to have the dog snot run out of...
A modified engine has the ability to make better power throughout the range, verses a stocker that has to have the dog snot run out of it to get even close to what the mod engine produces.

If you have a 250F that makes 43HP at 10,000 rpm verses a stocker making 36-38HP at 12,000 rpm, the reliability of the stock engine is greatly reduced. The mod engine is working less to produce more.
It doesn't work that way. The formula for horsepower is:


HP = Torque x rpm / 5252


That means with engines of equal displacement the only way to build more horsepower is to increase the volumetric efficiency, through cam/porting/compression/exhaust/carb mods, and spin it faster.


The only way to make more hp at a lower rpm is to increase the displacement.
tunedlength
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tunedlength 7/23/2009 8:37pm
7/23/2009 8:37pm
why do you have to spin it faster to make more power?
CamP
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CamP 7/23/2009 9:08pm
7/23/2009 9:08pm
tunedlength wrote:
why do you have to spin it faster to make more power?
Torque x RPM / 5252
jtomasik
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jtomasik 7/23/2009 9:09pm
7/23/2009 9:09pm
CamP wrote:
It doesn't work that way. The formula for horsepower is: HP = Torque x rpm / 5252 That means with engines of equal displacement the only...
It doesn't work that way. The formula for horsepower is:


HP = Torque x rpm / 5252


That means with engines of equal displacement the only way to build more horsepower is to increase the volumetric efficiency, through cam/porting/compression/exhaust/carb mods, and spin it faster.


The only way to make more hp at a lower rpm is to increase the displacement.
Or fire it twice as much with a natural supercharger, making more torque.
Smile

Ain't two-strokes great?
Matt Fisher 7/23/2009 9:13pm
7/23/2009 9:13pm
An engine is an air pump. The more air it moves, the more power it can make. You can move more air by having a larger pump (500 instead of a 125), you can pump the air in/out faster via rpm's, and in both cases, you always strive to make your pump (large or fast) more efficient.

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