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Sutage
13th February 2006, 21:14
Hey
Are there are fuel injected 250 or 400 bikes out? Keen for turbo 250 but the conversion is too hard/costly

cowpoos
13th February 2006, 21:25
why...u don't need FI...blow through or suck through carb will be fine....cheaper than anything to do with reprogramming a factory FI from a 250-400 that with out a doubt won't be easy to re-programme...

just don't waste your money and get a bigger bike....or if you can't coz your on your learners....get a two stroker...rgv250 or kr1s 250...F'ing quick bikes....quicker than their spec's would suggest....

FlyingDutchMan
14th February 2006, 12:21
I'm going to FI my bike. Just a matter of getting the engine going first.

imdying
14th February 2006, 14:33
One has to ask why you would bother? A challenge is one thing, but pouring money down a hole is another. I would investigate aftermarket efi computers some, I wonder what one that supports 17000rpm in multipoint would cost?? Maybe they all do? Seems unlikely when there target market is cars?

marty
14th February 2006, 14:43
why turbo a 50hp 250 when you could just have this ??? >>>> http://www.trademe.co.nz/Trade-Me-Motors/Motorbikes/Motorbikes/Sports-tourer/auction-47852221.htm

kiwifruit
14th February 2006, 14:44
like cowpoos said, get a rgv or simalar if its power you want on a learner or resticted licence
they are very fast!!!

onearmedbandit
14th February 2006, 15:54
I think what imdying says is a good point. One of the reasons efi took a while to get to bikes (note, I say only 1) was due to the higher revs acheived by bikes and getting the injectors to fire at the correct intervals. Or so I read in a technical article on efi and bikes.

FlyingDutchMan
14th February 2006, 21:22
One has to ask why you would bother? A challenge is one thing, but pouring money down a hole is another. I would investigate aftermarket efi computers some, I wonder what one that supports 17000rpm in multipoint would cost?? Maybe they all do? Seems unlikely when there target market is cars?

Well my guess is it will cost me between $200-$300 for everything. I'm planning (and have actually started) to design the thing from the ground up (including the actualy microprocessor core hardware design), and will build it my self. I'll be getting rid of the butter fly valves and use my own custom method of regulating the air intake volume. I'm doing it cause I can, not because I want to waste money. I'm going to redo the ignition (theres an easy 5hp right there!). It's going to have mapping for lots of variables, and will have 2GB of space to store code/ignition/FI maps. Closed loop etc etc

FlyingDutchMan
14th February 2006, 21:28
I think what imdying says is a good point. One of the reasons efi took a while to get to bikes (note, I say only 1) was due to the higher revs acheived by bikes and getting the injectors to fire at the correct intervals. Or so I read in a technical article on efi and bikes.

I'll be surprized if that is the real reason - the electronics have been there for 10 years at least. The electronics I'm planning on using will probably be excessively overkill - I could probably run FI for 10 different bikes at the same time on the same device. But since I can get the expensive parts at 1000 up prices through work, it'll be cheap enough and work exactly how I want it to. If it doesn't I'll tweak so it does. Simple as.

cowpoos
14th February 2006, 21:34
Well my guess is it will cost me between $200-$300 for everything. I'm planning (and have actually started) to design the thing from the ground up (including the actualy microprocessor core hardware design), and will build it my self. I'll be getting rid of the butter fly valves and use my own custom method of regulating the air intake volume. I'm doing it cause I can, not because I want to waste money. I'm going to redo the ignition (theres an easy 5hp right there!). It's going to have mapping for lots of variables, and will have 2GB of space to store code/ignition/FI maps. Closed loop etc etc

well I think your full of shit....but prove me wrong....

Sutage
14th February 2006, 22:05
shrug why do i wanna turbo it? because then its turbo charged
i thank you all for your opinions but, are there any fuel injected 250/400s?
i can beat most cars that will race me, cant beat anything faster than a 250 bike tho, turbo would help plus keeping it 250
plus it goes pSHHH not RING DING DIN DING
two strokes sound fucking rude

FlyingDutchMan
14th February 2006, 22:19
well I think your full of shit....but prove me wrong....

Heres what some aussies have done (its goggle cached, cuase I can't seem to get to the actual pages).
http://72.14.207.104/search?q=cache:members.dodo.net.au/~aepl/cbr.html

http://72.14.207.104/search?q=cache:members.dodo.net.au/~aepl/cbr/cbr1.html
Can't seem to get page two up.
http://72.14.207.104/search?q=cache:members.dodo.net.au/~aepl/cbr/cbr3.html
http://72.14.207.104/search?q=cache:members.dodo.net.au/~aepl/cbr/cbr4.html

http://72.14.207.104/search?q=cache:members.dodo.net.au/~aepl/cbr/Turbo1.html
http://72.14.207.104/search?q=cache:members.dodo.net.au/~aepl/cbr/Turbo2.html
http://72.14.207.104/search?q=cache:members.dodo.net.au/~aepl/cbr/Turbo3.html
http://72.14.207.104/search?q=cache:members.dodo.net.au/~aepl/cbr/Turbo4.html

onearmedbandit
14th February 2006, 22:53
I'll be surprized if that is the real reason - the electronics have been there for 10 years at least. The electronics I'm planning on using will probably be excessively overkill - I could probably run FI for 10 different bikes at the same time on the same device. But since I can get the expensive parts at 1000 up prices through work, it'll be cheap enough and work exactly how I want it to. If it doesn't I'll tweak so it does. Simple as.


I didn't say it was the real reason, re-read my post and you'll see I say it was only 1 of the reasons development on motorcycle engines was slower. Sure the electronics for it probably did exist 10yrs ago, but that is only 2yrs before we started seeing mass production injected bikes on the market. (I'm thinking 98 GSXR750, correct me if I'm wrong - with the exception of the Kawasaki GPX1100 injected version etc). Injection in cars however was in common usage at the time, by the likes of Honda and Suzuki. Just because the electronics were around doesn't mean they were reliable in the harsh conditions that motorcycles encounter or that they were cheap enough to fit to bikes (a decent price rise for an injected bike that didn't produce much more power than a carb'ed model would be a marketing failure).

imdying
15th February 2006, 08:15
Sounds like you're going to have fun :)

The sort of memory that you want isn't particularly cheap, I'm not sure why you want to use 2GB of it. I would've thought 128k of storage for maps would've been sufficient? What rev/vac/tps/granularity of values are you planning on sampling at?

There's a small number of cheap readily available microprocessors you could use, might just be easier to buy one (you can generally get a developers kit from their websites for working with the instruction sets) than to make one yourself.

I think if might've been the speed of the older microprocessors (as often used in cheaper car diy efi systems) that was insufficient for high revving bikes. Also worth considering which injectors... you'll want a smallish unit to keep the duty cycle up, otherwise you'll have bugger all granularity there too. Can't suggest good units to use sorry.

I'd be suprised if as turbo 250 would be faster than a late RGV/RS anywhere but in straight line, maybe not even then considering the extra weight of a four stroke motor with a lump of cast iron bolted to it.

Not so sure on the $250-$300... inlet manifold, custom air metering thingy, injectors, ecu, wiring, fuel pump. A decent enviro resistant 20pin connector isn't cheap by itself.

Sounds like you're going to have fun :)

cowpoos
15th February 2006, 09:05
I didn't say it was the real reason, re-read my post and you'll see I say it was only 1 of the reasons development on motorcycle engines was slower. Sure the electronics for it probably did exist 10yrs ago, but that is only 2yrs before we started seeing mass production injected bikes on the market. (I'm thinking 98 GSXR750, correct me if I'm wrong - with the exception of the Kawasaki GPX1100 injected version etc). Injection in cars however was in common usage at the time, by the likes of Honda and Suzuki. Just because the electronics were around doesn't mean they were reliable in the harsh conditions that motorcycles encounter or that they were cheap enough to fit to bikes (a decent price rise for an injected bike that didn't produce much more power than a carb'ed model would be a marketing failure).

I think guzzi's hav had a few injected models in the earliy nineties as well...

Monsterbishi
15th February 2006, 09:14
Flyingdutchman, depending on when you get the project underway, I could have some small injectors towards the end of the year that should suit your application, Denso 200cc Top-feed, high impedance injectors, so should max out at about 27hp each.

They'll be from our Mustang, 44,000k's on them. It's a shame I didn't read this sooner, I had a alloy fuel rail that would have been perfect too that I binned.

FlyingDutchMan
15th February 2006, 12:19
Sounds like you're going to have fun :)

The sort of memory that you want isn't particularly cheap, I'm not sure why you want to use 2GB of it. I would've thought 128k of storage for maps would've been sufficient? What rev/vac/tps/granularity of values are you planning on sampling at?

There's a small number of cheap readily available microprocessors you could use, might just be easier to buy one (you can generally get a developers kit from their websites for working with the instruction sets) than to make one yourself.

I think if might've been the speed of the older microprocessors (as often used in cheaper car diy efi systems) that was insufficient for high revving bikes. Also worth considering which injectors... you'll want a smallish unit to keep the duty cycle up, otherwise you'll have bugger all granularity there too. Can't suggest good units to use sorry.

I'd be suprised if as turbo 250 would be faster than a late RGV/RS anywhere but in straight line, maybe not even then considering the extra weight of a four stroke motor with a lump of cast iron bolted to it.

Not so sure on the $250-$300... inlet manifold, custom air metering thingy, injectors, ecu, wiring, fuel pump. A decent enviro resistant 20pin connector isn't cheap by itself.

Sounds like you're going to have fun :)


Well I've got a 2GB SD flash card from my dad. The PCB in it was cracked, so he let me keep the flash chips if I could get the photos out of it for him. Damn cheap way of getting nv memory imo. Also will have plenty of space to have an imdependant map for each cylinder too - this isn't the initial plan, but will be considered if the variation between cylinders is too great. The timing resolution of the injectors/spark plugs will around the 100ns mark. One of the harder things will be accurately determining eactly where the crank is and when. More than enough processing power for 18,000rpm machine. (its only 300 rotations per second).

As for the microprocessor, I'll be doing it inside an FPGA, with my own custom instruction set (native handling of switch statements for one). Have some useful instructions unlike a lots of the damn things out there at the moment. Also since its an FPGA, do independant timing for each injector/spark plug etc, is a breeze since it lots of things can run in parallel on it (though a seperate microprocessor core for each cylinder is going a little too far me thinks).

Not really interested in doing a turbo though.

FlyingDutchMan
15th February 2006, 12:23
Flyingdutchman, depending on when you get the project underway, I could have some small injectors towards the end of the year that should suit your application, Denso 200cc Top-feed, high impedance injectors, so should max out at about 27hp each.

They'll be from our Mustang, 44,000k's on them. It's a shame I didn't read this sooner, I had a alloy fuel rail that would have been perfect too that I binned.

It sound awesome... I was dreaming about getting low impedance ones (they can turn on faster don't they?), but anything that is the right capacity will work fine. A basic fuel rail is pretty easy to knock up - some nice thick pipe with holes drilled at the appropriate spots. Pump one end, pressure regulator at the other.

R6_kid
15th February 2006, 12:41
as the aussie guys found out, the only way to get injectors that work properly at 18,000rpm is to talk the F1 people... and they arent gonna give it away cheap.

From memory that aussie guy managed to get it working, and it did give him more power but it was a shitter to start and sometimes would randomly cut out for no reason.

Good luck with it, i dont see why you dont just buy a bigger bike - no one picks up chicks on 250's trust me.

imdying
15th February 2006, 12:56
(though a seperate microprocessor core for each cylinder is going a little too far me thinks).

Not really interested in doing a turbo though.Hahaha, for sure. Don't ignore turbos though, you'll want one eventually :)

I wonder just how bad single point would be... Lowers the tech of pretty much every part, might be worth investigating. Should be easy to setup a crank trigger... I've some ABS sensor rings you could have it you like :)

stanko
15th February 2006, 19:50
I think the big problem will be with the injectors at 18,000 rpm that gives 3.3milliseconds per rev , but you have 2 revs per cycle so 6.6mS to do an injection cycle. I think thats about how long it takes for an injector to open and start flowing so while the electronics may be fast enough for a quick wank between injections the mechanicals will still be rubbing the sleep out of their eyes. If you have a really short time to inject the fuel increasing the pressure (normally 2 or 3 bar over manifold pressure) to about 10 bar might help.

FlyingDutchMan
15th February 2006, 22:05
I think the big problem will be with the injectors at 18,000 rpm that gives 3.3milliseconds per rev , but you have 2 revs per cycle so 6.6mS to do an injection cycle. I think thats about how long it takes for an injector to open and start flowing so while the electronics may be fast enough for a quick wank between injections the mechanicals will still be rubbing the sleep out of their eyes. If you have a really short time to inject the fuel increasing the pressure (normally 2 or 3 bar over manifold pressure) to about 10 bar might help.

Thats why I was interested in low impedance injectors - they can turn on quicker than high impedance ones. Involve a bit more electronics, but I handle that. Can do the same with the high impedance ones to by driving them with an larger voltage (more complicated than low impedance electronics)... 100 volts should kick those things open pretty quick.

But even if they stay partially on, by applying PWM you can adjust how open they are and still get reasonable (though not ideal) fueling.

imdying
16th February 2006, 10:14
still get reasonable (though not ideal) fueling.
Which sounds like what your (free ) carbs give you :/

DEATH_INC.
18th February 2006, 03:56
At high rpm your injectors are open most of the time anyway....unless your talking F1 stuff the operation is pretty basic, there's not a lot to be gained from firing the injectors sequentially either, most are just batch fired.
The abs ring idea is good,but you'll need to either fill in between two of the points or cut one out to give ya a reference....but why not just use the ignition trigger that's already there?
Another idea for high rpm, use two injectors per cylinder, firing them alternately....not that hard to set up.

cowpoos
18th February 2006, 07:09
no one picks up chicks on 250's trust me.

well I suppose your not me are ya.... :spudwave: