Most of the stuff I need for my 345cc engine I am about to build are already here or on the way...

anyway most of the info I need I gathered either from other posts here or digging around in the net... one thing I still need to know and haven't found anywhere yet is the 300's injectors' capacity... I still remember a post about the 250's which are same as a ZX-6R previous model and more than adequate for 125cc each but what about those of the 300 ?
are they the same? are they bigger-meaning are they feeding more cc/min?

The engine will have ported head, reprofiled camshafts (my design, quite radical), C.R. of 13,3:1 to 13,5:1, 67mm high domed pistons, 300 fuel pump and throttle bodies but european 250's ECU, PC V, a modified 250 yoshi full exhaust and- like I mentioned 14,5K rpm rev limit so I am aiming somewhere around 50+ rwhp
As you can see any detail is critical to such a highly modified engine...

I need one more piece of information... Could someone measure the outside diameter of the primary pipe of a 300 aftermarket full exhaust system ? Yoshi, Leovince, AreaP... any will do... just for comparison to my 250's yoshi system and which parts of it might I alter... the figure I need the most is the part just coming out of the port, near the mounting bolts and myabe a couple of inches after that, a tiny bit after the first turn.

A handful of views here, but no responses as of yet. Free bump to try and help out.

Can't help with either but you may try contacting Kerry at Area P regarding it. Why the outside diameter though?

As for the injector flow rate I would not know without having a shop test it which I have neither. Could you cross reference the part numbers and see?

I would say just run it and see. I am not sure how much the pc5 can compensate.

hope that since using the 300 fuel pump, the PC V will cope just fine...
I am receiving my new 300 TBs due Monday and will soon measure its injectors...
as for the headers, primary exhaust pipes, I asked for the outside diameter just because I thought it would be easier for an owner to just take the tool and measure it on the bike....

in the meantime I am taking time to do things right and save the necesary funds for my project... recently got my full aluminum block and piston kit which was originally made for the 250 but will fit in the 300 engine
its 67mm high comp pistons are work of art, with short but wide skirt and ceramic coating... the problem is it is SO much heavier !!
while stock 250 is 124gr, JE 64mm is 148gr, this thing is more than 154grams...
my 14350 real rpm ECU will not be gentle to rods and might send the whole thing apart in seconds... so I need to lighten it quite a bit without weakening crucial points were forces are applied... keeping photo record, once I get things sorted out and my hands on that 300cc engine I will start showing the whole preparation I'm already making for its schwarzeneggering (couldn't help it)...or what else would I call that?? hahaha

time to call crowder I think for custom rods, the stock ones seem like they would pull apart with that extra piston weight. Maybe some else can chime in. Also not sure but maybe you can run higher fuel pressure to compensate for the larger displacement. I don't have experience with motos but messed around with cars.

time to call crowder I think for custom rods, the stock ones seem like they would pull apart with that extra piston weight. Maybe some else can chime in. Also not sure but maybe you can run higher fuel pressure to compensate for the larger displacement. I don't have experience with motos but messed around with cars.

Of course I could use a pair of custom rods, but I am across the ocean, in this tiny country called Greece and I don't believe that anyone would be very excited about making and sending a single pair of rods that have no demand in the market just for a crazy guy somewhere in Europe...well at least not at a price I could afford
as for a rod interchange from another, not the slighest chance...unfortunatelly both 250 and 300 have relatively compact rods in general and theoretically could fit sth from a 600cc but, well, no...they have small diameter base circle...
it is not easy but I will have to work on the piston top, take some material off and balance carefully... then will work on the head, grinding etc to counterbalance the lost CR...
you are right because it is common practice all that you mentioned but it can't be done in the 250/300 case...
as for the fuel pressure thing, definetely not necessary... cars have turbochargers, lots of displacement and other stuff that easily affect fuel pressure... bikes have much pressure... what might need improving in some cases is flow rate...anyway that's a whole different chapter...

guys I just checked on the 300's fuel injectors capacity and it is 210cc/min, think the same as 250's that is... so extra fuel comes from bigger fuel pump in 300 tank (compared to FI 250 mod), not injectors... they are also from a ZX6R but more recent and with better atomization than the 250's...

Good info! How did you test this? Homemade setup or shop?

checked it among some other "jiggling" on the TBs (removed secondary butterflies and axle, "blinded" the secondary tps etc) at my mechanic's shop with a battery power supply using a 300 fuel tank and fuel rail as if doing the service manual check... besides both of us are quite familiar with the ZX6-R green injectors and were pretty sure before we even started but needed to make sure just in case...
can't wait till Friday... whole engine along with cooling system, some handmade aftermarket whole exhaust system, fuel pump and the rear rim are on the way.... gonna be a very hot summer for me... decided to kiss vacation goodbye since my pockets are empty...back to "school", a month of studying and measuring the engine's internals crash-course... :bounce:

Has anyone actually had their injectors flow tested to see what cc/min they are? I have a set and may do a test here shortly but I figured I'd ask.

Just some info the 300 injectors are not used on any other bike other than the 300 Same goes for the fuel pump:

EX300ADF (Ninja 300) (2013)
EX300ADFA (Ninja 300) (2013)
EX300AEF (Ninja 300) (2014)
EX300AEFA (Ninja 300) (2014)
EX300AES (Ninja 300) (2014)
EX300AESA (Ninja 300 SE) (2014)
EX300BDF (Ninja 300 (Canadian)) (2013)
EX300BDFA (Ninja 300 ABS) (2013)
EX300BEF (Ninja 300 ABS) (2014)
EX300BEFA (Ninja 300 ABS SE) (2014)
EX300BES (Ninja 300 ABS) (2014)
EX300BESA (Ninja 300 ABS SE) (2014)

Part Number: 49033-0558
Description: NOZZLE-INJECTION
Package Quantity: 1

it is true that all fuel delivery parts of the 300 have different codes than any other kawa model...however all features of the bosch injectors are identical to the zx-6 both for the 250 as for the 300...on the other hand the 250 injectors have different hole pattern than the 300 which theoretically gives an advantage atomization-wise to the 300...and each pair of them is being used in different genaration zx-6 european models with different codes (don't know why...)
anyway there may be such differences between the american and european versions...
their capacity was measured the same but the 300 fuel pump (which is indeed uniquely made for and used so far only in the 300 and thank you for pointing that out) is capable of 3times more fuel delivery (compared to the 250 efi fuel pump in my european model) while still working at the same fuel pressure (43psi)...so, yes, there is a huge difference no matter on what perspective we compare the two...

For information:

Kawasaki Part # 49033-0558
DENSO Part # EAT-811

Injector Flow = 175cc/min @ 43psi

:thumbup:

From RC Engineering's website using their calculator, each injector is able to flow enough fuel for 26.64hp per injector or 53.28hp for the two before you max them out. Those are just calculations but RC's stuff is decently close.

well I will take that as a more reliable source and consider this info as more accurate...
thank you Shawn for taking time to look through that...
on my throttle bodies I can see the "EAT811" code but I can also read a tiny imprint "Bosch license" on the side they get wired, hope we're talking about the same for sure...
by the way, could you provide me with some info about the exhaust headers of the 300
inside or outside diameter so I can compare to the ones I have in hand...oem or aftermarket will do, just to know if I really need to change my exhaust system...
mine are outside diameter 31mm (1,22") at 2in. from head exhaust port and 32mm (1,26") from a little bit after till the turn below engine...midpipe starts from 44mm (1,73") after the "joint" and widens up to 51mm (2") just before the can...

I cannot actually I am doing a 300 EFI system conversion on a 09 250r so I am dealing with the fuel side only. Turbo fuel injected 250 on the way!!! :D

well I will take that as a more reliable source and consider this info as more accurate...
thank you Shawn for taking time to look through that...
on my throttle bodies I can see the "EAT811" code but I can also read a tiny imprint "Bosch license" on the side they get wired, hope we're talking about the same for sure...
by the way, could you provide me with some info about the exhaust headers of the 300
inside or outside diameter so I can compare to the ones I have in hand...oem or aftermarket will do, just to know if I really need to change my exhaust system...
mine are outside diameter 31mm (1,22") at 2in. from head exhaust port and 32mm (1,26") from a little bit after till the turn below engine...midpipe starts from 44mm (1,73") after the "joint" and widens up to 51mm (2") just before the can...

Nick as an info and please notice that I 'only' have the 250 with the Leo-Fullsystem - where you talk about 32mm (1.26") I measure 34mm (1.34").
Hope that helps a little bit, also for you good success and luck. :thumbup:

PS: One more thing, though I'm sure you know, but sometimes the people forget about (like me before editing) more important than the diameter is an absolute equal length of the two pipes (what my Leo-Fullsystem has since I'd measure before install).

And after reading the info about the 300 injectors I guess the best way to go is with the 250 injectors with their 200cc/min @ 43 PSI (Info here: https://www.ninjette.org/forums/showpost.php?p=413571&postcount=193 ) plus the 300 fuel pump.

Or you can smack some ZX10r injectors in there if you really need them ;-)

330cc's That should be good for high boost and E85!


As far as pumps, has anyone actually measured out how much LPH the stock ones flow? I will be using an exturnal inline so this wont apply to me but may be useful to others... Service manual online only has a spec of 50mL when on for 3 seconds.... doing some math that winds up only being 60 LPH?

Nick as an info and please notice that I 'only' have the 250 with the Leo-Fullsystem - where you talk about 32mm (1.26") I measure 34mm (1.34").
Hope that helps a little bit, also for you good success and luck. :thumbup:


well that means I need bigger pipes...my Yoshi is ok as far as equal lengths are concerned but it's good you pinpoint that...it's true that some pay that little attention...
thank you for your support and help... try measuring some more points for me if you get a chance on your LeoVince...

PS: One more thing, though I'm sure you know, but sometimes the people forget about (like me before editing) more important than the diameter is an absolute equal length of the two pipes (what my Leo-Fullsystem has since I'd measure before install).

And after reading the info about the 300 injectors I guess the best way to go is with the 250 injectors with their 200cc/min @ 43 PSI (Info here: https://www.ninjette.org/forums/showpost.php?p=413571&postcount=193 ) plus the 300 fuel pump.

Well, that's exactly the way I'm going... 300 fuel pump with 250 injectors...

You might not even really need that 300 pump..... it all depends on how much flow it can provide before the 43psi drops off which from the looks of it it will take major fueling to run out or forced induction/nitrous.

Using some of the fuel pump calculators running 200cc injectors you only need a 24 LPH pump

What are you guys trying to accomplish using a larger volume pump?

Or you can smack some ZX10r injectors in there if you really need them ;-)

330cc's That should be good for high boost and E85!


As far as pumps, has anyone actually measured out how much LPH the stock ones flow? I will be using an exturnal inline so this wont apply to me but may be useful to others... Service manual online only has a spec of 50mL when on for 3 seconds.... doing some math that winds up only being 60 LPH?

Shawn if you're going to turbocharge that thing you will definetely need a bigger fuel pump, for safety and being able to play more easily with boost pressure without being on the edge of the fuel delivery system either injector-wise or pump-wise... most guys here in Europe use Wallbro in-tank models in place of factory piece which are relatively cheap and extremely efficient (use in turbo cars too) and can be combined with external filter for easy check and change...
now as far as the math is concerned, IF the fuel pump gives the same constant supply, it is 50mL/3sec X 20sec =1000mL=1L/min X 60 = precisely 60L/hour (did the math for others to see how we calculate that kind of stuff...)
so I guess you need something bigger and in combination with an external adjustable fuel regulator...
I hear rumors that 300 rods are quite stronger than 250's... take that into consideration too...

You might not even really need that 300 pump..... it all depends on how much flow it can provide before the 43psi drops off which from the looks of it it will take major fueling to run out or forced induction/nitrous.

Using some of the fuel pump calculators running 200cc injectors you only need a 24 LPH pump

What are you guys trying to accomplish using a larger volume pump?

250 efi european models use a 43psi, 18mL/3sec pump and my 39,5 rwp 250 engine with almost 14,5k rpm was almost starving at the high end (high comp, wild cams, bigger TBs, PC V full Yoshi exhaust etc)
so now that I'm going for the 300 engine + oversize bore kit at 67mm pistons and 300 ported TBs at 33mm and cams and high comp and ported 300 head and 14,5k rpm among other stuff, I think I'm gonna need all of that... at least...

Got ya!

As far as my project yes I'll be running an exturnal pump and regulator.... happen to have a spare set laying around the garage :D


Oh wow!!! that 250 pump does not push out that much fuel huh! 21.6LPH?

Question for you... I know that in the service manual it is stating 18mL per 3 seconds but have you tried to actually measure out what it will really flow?

Using a graduated cylinder or even a ratio rite cup that can measure cc's just make a jumper wire to put 12V to the fuel pump for 1 minute might show a different result. As the manuals normally will say at least 18ml @ 3 sec might be more?

Another thing to consider is have you watched the duty cycle of the injectors your running?

Just throwing ideas at ya!

Nice of you to throw such ideas to consider, helps me a lot to discuss some of the problems I am encountering with you guys...now for the joke of the month: gasoline in Greece...
some say it is some kind of petrol origin fluid but nothing to do with gasoline... it's some chemical composition noone really knows about like some magic secret kept in the vaults of what we call gas stations... it appears to be partly unleaded gasoline (about 90%) and the other 10% can be some (or even all) of the substances below in unknown proportions:
petrol - diesel engine fuel that is...
petrol we use for heating appliances
water !!! or...
special (hahahaha)additives that have nothing to do with improving engine's performance, durability or anything else useful as a sense... and now for the good part...
mud, oh yes MUD, sand, tiny bits of stone ,concrete, glass or plastic and so on...
all we know it's called "the juice"...
you see there is no stock fuel pump of any bike or car that lasts more than 2 years (that is IF you are lucky of course or buy from certain rare stations that are merely less dirty than the rest... sad story... so you see it is a very fortunate case if anyone should find their fuel pump to be as close as 10% less than what the manual says after 6 months of use...
18mL/3 sec... Oh God what a joke !! maybe before we fill the tank with gas...

I hope you can see my point...I know it is hilarious but also sadly true... so you see there are more ZX10, gixxers, busas, R1s etc with aftermarket fuel pumps than with exhausts or PC Vs... the rest... well you can see them commuting every time they reach 10k rpm...

Ok, MY fuel pump was being checked and cleaned (had a small removable filter in place of stock) every 3 months or so and was ok after 2 years of service at 19mL/3 sec...but there were areas on my PC V map where duty cycle was up to 78% more than stock and that is just a tiny bit away from the limit(and we're talking about the 250cc efi engine, highly modded but not close by any chance to the 345cc I am about to put together...I had to use some bigger yamaha injectors which were ok but increased fuel consumption by 15% without improving performance by more than 1% (don't know how many cc/min but they were at least 300cc/min judging from the negative values on the map, which I had to fix all over again...)

Wow that is crazy! If it wasnt such a pain in the butt I'd just filter the gas before it went in the tank but uhhhh yeah that sucks!!! I thought we had it bad with our measly little 10% ethanol!

Do they offer anything like E85 fuels over there?

E85 ?? I've no idea what that is...
there is some kind of high octane or "highly oxygenated" -as we call it- racing fuel in the market which costs about 11 euros (12 $ or more and that is per liter, a bit more than half a gallon ...) but few get access to it and even less have the funds to get their hands onto some... that's why most guys who compete in dragster here tune their bikes to work with normal or "premium" gas holding back on ignition timing and compression ratio...

micoulisninja, I must admit that my tool for measuring is not one of the most exact when I'd tell you 34mm since it showed a little bit more but I was rounding off instead of up.
So here's the original description from my exhaust (showing 35mm).

I'm using the db-killer no. 32BF instead of the 32B, which is fully open and also very noisy, but the 32BF is giving more back pressure and also more power what's really perceptible.

micoulisninja, I must admit that my tool for measuring is not one of the most exact when I'd tell you 34mm since it showed a little bit more but I was rounding off instead of up.
So here's the original description from my exhaust (showing 35mm).

I'm using the db-killer no. 32BF instead of the 32B, which is fully open and also very noisy, but the 32BF is giving more back pressure and also more power what's really perceptible.

excellent !!! thank you so much !!! it shows exactly what I need to compare... and to be honest differnces from my full Yoshi are minimal -if any-mostly because yours widens quite a bit down the primary pipes and mine is more straight tubed... secondary and final are almost identical... well that tells me I am going to need something much bigger for that new engine... thanks again !!!