All Things Moto! Dirtbike Forums

All Things Moto! Dirtbike Forums (
-   General Discussion (
-   -   Electronic Injection (

Crazy 04-11-2004 06:30 PM

Electronic Injection
Im thinking about designing and testing an electronic injection system for all bikes. Well all bikes that have a lighting coil at this time. My goal would be to be able to be able to incorperate it with the CDI and be able to adjust timing along with exact fuel control so that you would never have to change a jet.

Does anybody think this would be worthwhile? If so ill start designing.

Let me know what you think of the idea and what you think also could cause problems or come into play.

Honda_Rider_XR 04-11-2004 06:50 PM

Re: Electronic Injection
Sounds complicated..

YzRacer#53 04-11-2004 07:34 PM

Re: Electronic Injection
If its possible which it is it would be worth it totally, you could make a lot of money.

ThumperCRF250 04-11-2004 08:09 PM

Re: Electronic Injection
im with honda_rider and YZracer both ,, would it replace anything , or would it just attach to a part of the bike

dirtytrixx400 04-11-2004 08:11 PM

Re: Electronic Injection
well...good idea...but its been on the drawing boards for some time.i remember seeing a show on discovery channel(i think it was)several years ago about direct injection for bikes...offroad bikes in particular...they were testing a cr250 honda in australia with their system(i can't remember if it was a honda co. project or if it was a co-op deal with another co.). i do remember that they were claiming a huge increase in power and mpg,and a huge decrease in emissions. i recently ran across this site...i believe this is what the future holds for us.

YzRacer#53 04-11-2004 08:17 PM

Re: Electronic Injection
Nice link

dirtytrixx400 04-11-2004 08:21 PM

Re: Electronic Injection
wanted too add....haven't you wondered why the new bikes all are using more "smart"cdi's and exhaust valve controls and throttle position sensor's? >>>>>pre-runner systems for fuel injection!!

YzRacer#53 04-11-2004 08:27 PM

Re: Electronic Injection
They will be fuel injected soon I cant wait to see a efi 2 stroke it would HAUL A$$

Jaybird 04-11-2004 08:45 PM

Re: Electronic Injection
Direct Injection is already a reality on dirt bikes.
I got to see a prototype last fall on a 250exc.

The thing is really a great idea, but like most things there are downsides. The DI gives up a slight bit of HP on the top end, but this is only compared to a properly tuned, conventional carbed, two-stroke that is on the jagged edge of lean where the optimum power is created. (I'd venture to say there are very few here running to that tuned standard anyway).
The low end actually shows gains in HP from the conventional carb.

Stay's here.
And if you are going to build one...better get your thinking cap on. :)

Crazy 04-11-2004 08:47 PM

Re: Electronic Injection
thx for the link to that site im sure it will be very helpful. Ive read many things about how efi cars work and all the different types. being that this will be a single cylinder i think ill be able to pull it off. the only thing that would have to modified on bikes that didnt have a lighting coil could be to change the stator assembly to one that had it. Another option would be on the idler pully type generator, it would just run off of the stock chain on the swingarm. I have an extra OLD school thumper that im going to try the idea on.

The idea of the idler type generator on the swingarm would be a more retrofit type idea that would fit more bikes with ease, but then issues of water getting on it would be an issue. The only other thing that i thought would be a problem was the energy needed to run the fuel pump.

DaveS 04-11-2004 10:07 PM

Re: Electronic Injection
A tough obstacle in retrofitting a two-stroke to direct injection is bottom end lubrication. It's no easy task and was a big factor in putting these guys out of business.

dirtytrixx400 04-11-2004 10:47 PM

Re: Electronic Injection
that's a good valid point.....the show i saw wasn't that in-depth on the injection process....they only hit on the highlights...told about the good points.i was wanting more info...but you know how tv is,lol.back when i saw that...there wasn't even any street bikes using injection yet.surely the lube problem can/has been figured out now...maybe an independent oil injector into the bottom end???

DaveS 04-11-2004 11:26 PM

Re: Electronic Injection
The old Kawasaki triples' main bearings were lubicated that way. The oil was pumped in to the crankcase via the main bearings and the fuel charge would dissolve the oil and lubricate the top end and rod bearings.
I've thought that the clutch side crank seal could be moved to the inside and let the tranny fluid take care of that bearing. Then pressure lube the flywheel side bearing with two-stroke injection oil. Maybe that main bearing could be double sealed and the crank drilled to feed the oil to the bottom rod bearing?
I've also wondered if the reed cage couldn't be modified to act as the throttle body? This would open up some room for the air flow sensor.

dirtytrixx400 04-11-2004 11:53 PM

Re: Electronic Injection
lol...if we keep building on this thread topic...we are gonna need to get some patent rights...j/k. thats another good point about the reeds.....but actually without the carb....that space is perfect for a air meter(mass air type). and of course the need for a cable could be elimanated too....could use a "drive by wire"system. hmmm...i'm thinking...put a rev-lock clutch on it too....get rid of the clutch cable

dirtytrixx400 04-12-2004 12:18 AM

Re: Electronic Injection
this was a good topic to bring up 95whtyz.let us know how your doing on your project as it progresses. don't forget too add a port to the processor so we can "hot-rod" our own fuel and timing curves into it! i'll gladly trade all my jets and needles for a injection system.

Roostman 04-12-2004 12:28 AM

Re: Electronic Injection
Didnt the factories all run FI on the 125, 250 and old 500cc GP road bikes (I could be wrong)? Im sure the big boys have invested tons of dough into this already, but hey, more power to ya! Good luck.

TrickCr 10-17-2004 10:44 PM

Re: Electronic Injection
You guys are forgetting cannondale! They have instant throttle response. Very fast but no reliability.

All times are GMT -6. The time now is 10:00 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright ©2002-2017, JDub Consulting, Inc. All Right Reserved.