Italians really know how to tune a Ninja

[Somchai]

Today I found the following info in the net and surprise, no joke a perfect tuned 250 has more power with a higher rpm limit then the 300 (maybe it's cos of the better ignition like the first gen is also better then the newgen).

It says the thick line is the 250 (rev limit 13462 rpm)



This is the values (it's italian-ps, that means without aggregates - so at least subtract rd. 3 to 4 ps)



And this at least the document



And yes, the price for the race ready 250 is 41% more...

[Alex]

(now let's put those same mods on the 300 )

[Motofool]

Why is the max power recorded at 127 km/h (79 mph)?

[Alex]

Dynos typically use 4th gear (or whichever gear is closest to a 1:1 ratio). The theory is there is the least friction and therefore the least lost power in that gear.

[dfox]

in summary, a modified 250 has slightly more top end than a stock 300?

the 300 graph still looks more fun to ride though, those extra little torque bumps lower in the RPMS's are worth more than a slight increase in hp at the high end. Area under the curve ftw.

guess it shows that it's not really worth a power upgrade if you already own a 250, and wouldn't mod the 300.

[psych0hans]

Yeah, but look at the costs... :roleyes:

[Snake]

With that much cost you might as well just get a bigger bike.

[mgentz]

Originally Posted by Snake

With that much cost you might as well just get a bigger bike.

Oh don't you start...

[alex.s]

they got more power from the 250???

[Snake]

Originally Posted by mgentz

Oh don't you start...

Lol, sorry.

[dfox]

Originally Posted by Snake

With that much cost you might as well just get a bigger bike.

unless you already own the 250.

[crazymadbastard]

makes sense that the 300 makes more torque down low due to dispalcement, however at the top it dies due to the head not flowing enough to keep up with the air requirements of the bigger motor.

[Snake]

Originally Posted by dfox

unless you already own the 250.

Yes I already do own a 250 and I have to admit that I have done a few mods over the years .

[Jiggles]

Originally Posted by crazymadbastard

makes sense that the 300 makes more torque down low due to dispalcement, however at the top it dies due to the head not flowing enough to keep up with the air requirements of the bigger motor.

Also the 300 is stock....

[Racer x]

Am I reading this right? 45 hp and 20 ft lb of torque.

[lgk]

Originally Posted by Racer x

Am I reading this right? 45 hp and 20 ft lb of torque.

surprised me too.
i didnt think it was possible to get 40hp with NA

[mgentz]

They use a different measurement. It is not hp. Kind of like how some use nm and we use lb-ft.

[alex.s]

Originally Posted by mgentz

They use a different measurement. It is not hp. Kind of like how some use nm and we use lb-ft.

https://en.wikipedia.org/wiki/Horsepower#CV

[dfox]

Originally Posted by Snake

Yes I already do own a 250 and I have to admit that I have done a few mods over the years .

"you" wasn't directed towards you (snake), it was used as the "collective you", or the informal third person use of you, referring to anyone.

to make it easier to understand, I'll put it in the more formal third person. If one has a 250, but wants a bike that has as much hp as the 300, one doesn't need to buy a new bike to do it, and can probably save money since one already has a 250.

[lgk]

i don't know how their economy works, but i dont see how anyone could spend an additional $7200, to make a 250 to a comparable 300....


unless the taxes are past the $10k mark
i would seriously think about just improving a new 300, or getting a 600.

[mgentz]

Originally Posted by alex.s

https://en.wikipedia.org/wiki/Horsepower#CV

YEP. They use CV.

[alex.s]

Originally Posted by mgentz

YEP. They use CV.

maybe you missed my point where the difference between 45 hp and 45 cv is somewhere less than 1%

[alex.s]

Originally Posted by lgk

i don't know how their economy works, but i dont see how anyone could spend an additional $7200, to make a 250 to a comparable 300....


unless the taxes are past the $10k mark
i would seriously think about just improving a new 300, or getting a 600.

they are race bike engines. the point is that you have engine rules. so you could not actually run a 300 against 250s for example. so you are forced to buy the 250... but the 250 has more things you can do to it to get more power out apparently... so its more expensive. it only makes sense if you are already in a 250 class and have lots of 250 stuff and are deep into a 250 league.

[lgk]

Originally Posted by alex.s

they are race bike engines. the point is that you have engine rules. so you could not actually run a 300 against 250s for example. so you are forced to buy the 250... but the 250 has more things you can do to it to get more power out apparently... so its more expensive. it only makes sense if you are already in a 250 class and have lots of 250 stuff and are deep into a 250 league.

if the new motor has nothing to do with the stock motor then i understand the costs. it takes a ton of money to get proprietary parts.

I'm kind of curious how long the motor/trans lasts before a tear down.

[Racer x]

I know it can be done. My engine builder said we can get 45 hp. But he is taking too long. I am getting ready to pull the plug and send the motor to another motorcyle engine builder I know.

The secret to 45 hp is in the head. Bigger valves ,ports and different cam profiles.

[lgk]

Originally Posted by Racer x

I know it can be done. My engine builder said we can get 45 hp. But he is taking too long. I am getting ready to pull the plug and send the motor to another motorcyle engine builder I know.

The secret to 45 hp is in the head. Bigger valves ,ports and different cam profiles.

you think it can be done by porting the stock head?

[Racer x]

Not porting as in just grinding out the existing ports.
I do that and don't get near 45 hp.

But there IS room to enlarge the valves by 1mm. With bigger valves AND making the port shape to optimize flow at the desired RPM. And having the compression to pump the air. and the cams holding the valve open long enough and far enough to flow the volume of air and fuel you need . Then you make this type of power.

Then the valve springs need to be up to the job and the clutch and on and on. The 250cc moto GP bikes had decades of work and millions of dollars poured into them. This is an engine out of a 3500 dollar starter bike. It never stops amazing me how good this little engine is.

[mgentz]

Originally Posted by Racer x

Not porting as in just grinding out the existing ports.
I do that and don't get near 45 hp.

But there IS room to enlarge the valves by 1mm. With bigger valves AND making the port shape to optimize flow at the desired RPM. And having the compression to pump the air. and the cams holding the valve open long enough and far enough to flow the volume of air and fuel you need . Then you make this type of power.

Then the valve springs need to be up to the job and the clutch and on and on. The 250cc moto GP bikes had decades of work and millions of dollars poured into them. This is an engine out of a 3500 dollar starter bike. It never stops amazing me how good this little engine is.

I have all that?

[jonthechron]

Originally Posted by mgentz

YEP. They use CV.

CV = HP

CV is the french term used for Horse Power
CV stands for Cheval-Vapeur

Cheval litteraly means Horse and Vapeur means steam/vapor

[Somchai]

Originally Posted by Alex

(now let's put those same mods on the 300 )

Oh Alex, you're killing all my dreams...

[Snake]

Originally Posted by dfox

"you" wasn't directed towards you (snake), it was used as the "collective you", or the informal third person use of you, referring to anyone.

to make it easier to understand, I'll put it in the more formal third person. If one has a 250, but wants a bike that has as much hp as the 300, one doesn't need to buy a new bike to do it, and can probably save money since one already has a 250.

Why didn't you just say that?

[mania]

I was just looking at this topic & wondered
When the 300 first came out the first thing I looked at was how they got the extra
displacement
As we know they increased the stroke from 41.2 to 49mm but kept the bore 62mm exactly the same as the 250


Bore/Stroke gives a number & most sport or rev type bikes make a high number high being say above 1.2 & up
Square or torque type engines make a low number below that

Ninja 250 = 1.50
Honda 600rr = 1.57
Yamaha R6 is 1.57
Kawasaki ZX6R 1.57 till 2013 then 1.48
Yamaha R1 1.50
Ducati Panigale a whopping 1.84
Amazing eh how close those RR types are?

So Ninja 250 was in good company in this regard
Now look at the
Ninja 300... B/S = 1.26 ???
Actually dumb-ing revs down or torque-ing it up...Making it more "user friendly"
Not unlike the new Honda 500's which not surprisingly B/S= 1.0

Nothing wrong with that of course All fine & well
Made me wonder about the other direction....Bore increase instead

They have 64 & 66mm pistons available or at least do for the 2012 models so out of
curiosity I looked at those numbers

The 64's yield a 265cc engine
The 66's yield a 282cc engine
What would that do to the B/S number keeping the same stroke as the 250

With the 64's it would be 1.55
With the 66's it would be 1.60

Right around that 1.57 number the RR's like so much

I kind of wish this is the direction they went with the 300
Sure I understand everything is heading towards commuting town driving etc.
But still wonder what that would have been like.

[Racer x]

The first thing I would do to a 300 is bore and compression increase. 66mm an 12.5 to one. Then a bunch of head work. I just need an engine to work with.

[vanman69]

Originally Posted by Racer x

The first thing I would do to a 300 is bore and compression increase. 66mm an 12.5 to one. Then a bunch of head work. I just need an engine to work with.

heres one mate

http://www.ebay.com.au/itm/2013-13-4...item43ba54a725

although i paid less than that for the whole bike.

[Racer x]

That is what I paid for a 250 on 2008. The next one I bought was 200. I will have to wait.

[Jiggles]

Originally Posted by mania

I was just looking at this topic & wondered
When the 300 first came out the first thing I looked at was how they got the extra
displacement
As we know they increased the stroke from 41.2 to 49mm but kept the bore 62mm exactly the same as the 250


Bore/Stroke gives a number & most sport or rev type bikes make a high number high being say above 1.2 & up
Square or torque type engines make a low number below that

Ninja 250 = 1.50
Honda 600rr = 1.57
Yamaha R6 is 1.57
Kawasaki ZX6R 1.57 till 2013 then 1.48
Yamaha R1 1.50
Ducati Panigale a whopping 1.84
Amazing eh how close those RR types are?

So Ninja 250 was in good company in this regard
Now look at the
Ninja 300... B/S = 1.26 ???
Actually dumb-ing revs down or torque-ing it up...Making it more "user friendly"
Not unlike the new Honda 500's which not surprisingly B/S= 1.0

Nothing wrong with that of course All fine & well
Made me wonder about the other direction....Bore increase instead

They have 64 & 66mm pistons available or at least do for the 2012 models so out of
curiosity I looked at those numbers

The 64's yield a 265cc engine
The 66's yield a 282cc engine
What would that do to the B/S number keeping the same stroke as the 250

With the 64's it would be 1.55
With the 66's it would be 1.60

Right around that 1.57 number the RR's like so much

I kind of wish this is the direction they went with the 300
Sure I understand everything is heading towards commuting town driving etc.
But still wonder what that would have been like.

Yea I really wish the 300 revved as high as the 250.

Oh wait it does

[Alex]

Originally Posted by Jiggles

Yea I really wish the 300 revved as high as the 250.

Oh wait it does

They both have the same redline as set by the factory, but with the rev limiter adjusted, the 250 would be able to spin faster at the same safety margin. Rev limits are typically set by a max piston speed. Engines with larger stroke have a higher piston speed for the same engine speed. The 250 and 300 have very similar dimensions, except the 300 has a longer stroke.

[mania]

Originally Posted by Jiggles

Yea I really wish the 300 revved as high as the 250.

Oh wait it does

You poor thing

[Somchai]

A lil more info, after I'd read their race regulations for the series.
- Minimum weight is 123! kg (271 lbs, front stay and rear end are replaced with parts from aluminum).
- the diameter of the tb's at the 2-fiddy are extended to 30mm (from 28mm).
- there's many work done for the crankshaft and they have special camshafts, bigger valves ect. - the whole engine at least is redone.
- they use a complete new replacement-ecu, fully programmable.
- the 250ss is a real race bike - it also uses a slipper clutch (Type is the STM Evoluzione FKW-S070 which uses the oem-plates).

For more information you can look here: http://www.scuderiaplatini.it/

Look how they modify the airbox and gp-shift.







This is a pictures of how the STM slipper clutch is assembled.

[mania]

Originally Posted by Somchai

A lil more info, after I'd read their race regulations for the series.

Thanks Roland that is some very interesting info.

I like to watch Moto3 & am always impressed with what they get out of their single cylinder 250's. Also always wished they allowed the twins

Thanks for the links & pics !