Yamaha YZ 250 EFI

[Flettner]

http://youtu.be/hOGZ5llowoU

Some might be interested.

[Stylo]

Great work and 10 points on the video, any comments on the power vs the standard carb at this stage ?

[Pk33]

Good stuff. Keep it up. Why arnt the factories doing this??

[BMWST?]

Good stuff. Keep it up. Why arnt the factories doing this??

cos the fueling is only half of the problem.The biggest problem is the a lot of oil used for lubrication is burnt with the petrol,not so good for emmisions

[Flettner]

Just thought it might be of interest to some people. I goes very well although we are still adjusting the fuel map. Looking to have it at trail blazer this week end for more testing.
Should have this beast there as well, it was the first twostroke I fuel injected, first mechanical then electronic ). Oil is the least of the problems but in this video the kawasaki is running 40 to one on ethanol ( effectively 20 to 1 ratio ) a little smokey but it's only castor and it's like this for safety under testing.


http://www.youtube.com/watch?v=eleqBGvOM4M&feature=share&list=UUoYhqhrdK9On_IfKGD31hGA

[Pk33]

cos the fueling is only half of the problem.The biggest problem is the a lot of oil used for lubrication is burnt with the petrol,not so good for emmisions

They've got it sussed on outboards so why not bikes?

[scott411]

They've got it sussed on outboards so why not bikes?

apprantly it has to do with the amount of power (amps) the direct injection requires, they can get it to work on multiple cylinder out board motors, but not on single cylinder bikes, (DI two strokes tend to be only on the bigger outboard motors at this stage)

it was said that Husqy had direct injection two strokes about to be released, I wonder if KTM has brought the rights to this technolgy,

Sthil has released two stroke concrete cutters now, i am not sure if they are direct injection or not,

[Pornstar]

Wow, looks like a winner, so will this be a retro fit as well as a possible OEM fuel system on new bikes? I know of a certain EXC 250 that might like one. Keep up the good work chaps.

[Flettner]

Epic Events trail ride on Saturday, lots of fun.
EFI twostroke at work.


http://i1056.photobucket.com/albums/t380/uniflow/IMG_8860_zpsd6b580d7.jpg

http://i1056.photobucket.com/albums/t380/uniflow/IMG_8844_zps7b02a2a2.jpg

http://i1056.photobucket.com/albums/t380/uniflow/IMG_8817_zps9e758176.jpg

[takitimu]

apprantly it has to do with the amount of power (amps) the direct injection requires, they can get it to work on multiple cylinder out board motors, but not on single cylinder bikes, (DI two strokes tend to be only on the bigger outboard motors at this stage)

it was said that Husqy had direct injection two strokes about to be released, I wonder if KTM has brought the rights to this technolgy,

Sthil has released two stroke concrete cutters now, i am not sure if they are direct injection or not,

It was 3rd party developed I heard ( husky's direct injection ), I wonder what rpm they can get a DI 2/ up to, be pretty dang cool a di 200 2/ that could pull 12k.

[ktm84mxc]

Does the rotary disc induction help with the fuelling ? I suspect it would as it will be more controlled than a piston/reed valve engine, now anybody got a RG500 engine to test on ?

[Flettner]

no, no real difference to fueling / tuning, but the rotary valve engine does have a stronger top end. This engine ( F9 Kawasaki ) features a sliding rotary valve housing. This changes inlet timing as the engine changes rpm so you can have late valve timing ( strong top end ) and yet still have mild timing at low speed for good low down pull ( all the advantages of a reed motor with out the top end gas flow drop off disadvantage). This sliding valve is varied by the computer driving an R1 servo motor. I am slowly building up a new engine to fit into a YZF 250 ( 0010 ). This will be a 350cc EFI, reverse cylinder, reverse rotation crank, variable rotary valve. I'm making the cases so they will fit straight into the alloy frame with no need to cut it.

http://i1056.photobucket.com/albums/t380/uniflow/704e15fd.jpg

http://i1056.photobucket.com/albums/t380/uniflow/0c93ef14.jpg

[xen]

Awesome man, great job!

[Flettner]

http://youtu.be/UEQli7nuak4

First time on a dyno

[Jay GTI]

You Sir, are my new hero...

[oldskool]

http://youtu.be/UEQli7nuak4

First time on a dyno

Heya,
Great stuff!!
How did the readings compare to a normally aspirated YZ250 on the same dyno?
Was it an inertia drum or did you have some sort of calibrated mechanical load on it?
What gear was it in when the reading was grabbed?

[Flettner]

http://youtu.be/ifSEql1X4R0

EFI Kawasaki Bighorn dyno run and tuning. Air cooled 350cc running on ethanol. Link injection controller. Took a few runs to get it right.

[Flettner]

http://i854.photobucket.com/albums/ab102/GerbilGronk/Random%20Shots/IMG_8929_zpsccfc0f9d.jpg
http://i854.photobucket.com/albums/ab102/GerbilGronk/Random%20Shots/IMG_8928_zpsfe2f88c5.jpg

Took the EFI YZ250 to the Epic Events ride Taupo / Napier road yesterday, in the rain. Performed flawlessly though out the whole day. Tuned to give smooth broad power, best for these conditions. It's a lot of fun to ride, this is the first ever "Event" it's been to.

[FlangMasterJ]

This is great! Well done guys.

[Flettner]

Both EFI bikes will be at Maddix Park in Tauranga this Saturday afternoon.

[fridayflash]

very interesting stuff, would love to see the run, kwacka looks and sounds great!

[cheese]

Dam it, I'm going to Pirini.....

[Flettner]

This EFI YZ is available to view at Blackwood Yamaha, Cambridge, any time during opening hours, I'm sure Wayne would like to have a chat about it's construction / performance. The bike will be at Epic Events trail ride next weekend for more testing / tuning.

[Flettner]

http://youtu.be/1YG9ko8-Nwk

[Flettner]

The EFI YZ will be at the Redwoods ride tomorrow, if anyone is interested in viewing it.

[Flettner]

EFI YZ 250T will be at the Acerbis 4 hour, in the teams class.