EFI 2 stroke enduro bike.

[noobi]

And its not a KTM, its an Ossa
250381
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250386

OSSA ENDURO 250i/300i
Engine
Type: 2 stroke single cylinder with Kokusan twin injector, admission by
V-Force3 reed rox and electronic exhaust valve.
Displacement: 249 cm³ (250i)
Bore: 66,4 mm (250i)
Stroke: 72 mm
Starter: Electric start- ACG Starter Generator Kokusan
Gearbox: 6-speed, removable cassette type
Primary reduction ratio: 21:51
Secondary reduction ratio: 12:48
Clutch: Hidraulic Wet 3-disc.
Ignition / Fuel System EFI Kokusan twin-injector
Chassis
Frame type: CR-MO – Two side detachable frame
Front suspension: Öhlins Up Side Down 48 mm TTX
Rear suspension: Öhlins TTX
Front suspension travel: 300 mm
Rear suspension travel: 335 mm
Brakes: Disc brakes, Brembo floating calipers
Front brake disc: Wave – 260 mm
Rear brake disc: Wave – 220 mm
Chain: 5/8 x 1/4″
Wheelbase: 1.470±10 mm
Ground clearance (unloaded): 355 mm
Seat height (unloaded): 960 mm
Tank capacity: 9,8 l (aprox) unleaded gasoline mixed with 100% synthetic
2 Stroke oil
Dry weight: 97 kg (aprox)


I don't think the cone pipe and the TTX will make it to the production model somehow.
They are working on 20 pre production models, and plan on having full production by June 2013.

[Crasherfromwayback]

Looks pretty funky!

[george formby]

:facepalm:

That expansion chamber may cause infertility.

Neverthless, it's a 2 t so I likey.

[Jay GTI]

No real surprise it's not a KTM, Ossa already have the injected 2T trials bike and had made it known they were working on an enduro bike as well. I KTM were looking at the concept as well, but a lot of their R&D budget was wiped out by the failure of the X-Bow, so have been focusing on what they know they can sell.

Veeeeeeery interested in how it performs though!

[noobi]

:facepalm:

That expansion chamber may cause infertility.

Neverthless, it's a 2 t so I likey.

4 stroke headers run much hotter than expansion chambers and there seems to be no issues with the backwards engine yzf450. So I think fried balls wont be a problem. Which is always a bonus.

[george formby]

4 stroke headers run much hotter than expansion chambers and there seems to be no issues with the backwards engine yzf450. So I think fried balls wont be a problem. Which is always a bonus.

I was thinking more of the ring, ding, ding vibrations with me tongue in me cheek. Certainly clever design. I'm too thick to figure out if the weight distribution will improve the handling or not though.

[Jay GTI]

I was thinking more of the ring, ding, ding vibrations with me tongue in me cheek. Certainly clever design. I'm too thick to figure out if the weight distribution will improve the handling or not though.

It is a clever design and will protect the expansion chamber nicely. I got real sick of coming back from a ride with my old RM and finding yet another dent in the pipe... of course I could have tried staying on a bit more, but then I wouldn't have been riding hard enough*







* yeah like riding hard enough had anything to do with me falling off :facepalm:

[motor_mayhem]

Good to see someone doing something towards it.

The talking about a DI 2 stroke enduro/mx bike has probably consumed about 3 times as much time as the development of said bike. While I am a 4T fan, I like to see them kept honest.

[ktm84mxc]

Will be interesting to see what a production bike is like, can only be a good thing R&D for 2 smokes.
All it needs is a major manufacturer to take the ideas.

[K6K]

the thing I found interesting was the twin injector setup, one in the crank and one in the cylinder (not the head like most DI).
So the crank injector would take care of the lubrication rather than the oil injectors on the DI ski doo snowmobile setup.
There would still be the usual 2T fuel loss straight through the exhaust port but you could probably still do some late fuel charging with the cylinder injector to run it with some good power.

[peadub]

I still don't think we need fuel injection on two strokes just yet People buy 2Ts because they can work on them and they're are relatively cheap to maintain The extra fuel consumption and emissions is not a concern They are after the simplicity and I can guarantee we will sell less two strokes when they are FI
I had to retreive two bikes after last weeks Belray Both four strokes with fuel injection failure!

[Pornstar]

could be an OSSAume bike, or concept.

[NordieBoy]

Check out the right hand side of the swingarm...

:niceone:

[barty5]

Check out the right hand side of the swingarm...

:niceone:

Take it your talking about the pivot point being off the linkage? Odd set up.

[SMOKEU]

Are EFI 2 smokers generally less prone to seizing than carbied 2 strokes?

[Stylo]

The concept looks good , any idea of the relative HP figures compared to a current 2T and, is there still an old school powerband that makes the current 2T's so much fun ?

[Pornstar]

The concept looks good , any idea of the relative HP figures compared to a current 2T and, is there still an old school powerband that makes the current 2T's so much fun ?Hmmmmm? Indeed.

[Pornstar]

Are EFI 2 smokers generally less prone to seizing than carbied 2 strokes?Yes and No really, sometimes on occasion, but practically never.

[eelracing]

http://www.befurious.com/ossa-presenta-en-milan-las-novedosas-ossa-enduro-250i-y-300i/

Is the tide starting to turn? If the japs don't hurry up and smell the coffee they may be left behind.

Ossa,Bimota,Fantic and KTM etc are the future,long may they run.

[Jay GTI]

There's definitely some truth in that statement. Not sure about the other brands, they are still rareties in NZ, but certainly over the last few years KTM have made huge in-roads into the NZ market. Back in '06, when I got back into riding, there were a few KTMs around but now you go out somewhere like Woodhill and they are everywhere.

In fact all my riding buddies are on orange bikes now, some merely for the fact that the KTM MX range have electric legs, which I notice none of the Japanese bikes have followed suit with.

[CRF119]

Waiting for direct injection :)

[noobi]

Waiting for direct injection :)

I hear this often, why do you say that though?

[flyingcr250]

Waiting for direct injection :)

Youll be old gray and in a wheel chair wearing a nappy before that happens.......

[CRF119]

Direct injection is far more efficient but the problem is you need to over come the pressure crated by the compression so you would need a 300psi fuel pump to inject the fuel just at the right time.

I am assuming you have all seen this

http://www.youtube.com/watch?v=TE5ENcMH1ZI


I was a told by a engine builder and tuner that a two stroke will always make more power using a carby anyway. He used to build and tune the old 2 stroke road racers at world class level. He also used to make the expansion chambers for them and do all engine mods. He said a good CR500 should make 100hp :) if it doesn't it was done wrong.

Speedway cars still use carby to

[Jay GTI]

Speedway cars still use carby to

Not really a good comparison, speedway cars are basically tuned for WOT and there is little benefit of FI over a carb if all you're doing is hard on the gas, off the gas, hard on the gas, high revs at all time...etc.

An enduro bike will spend a lot more time on part-throttle, holding revs at a constant (ish) for short periods, running at low revs in the tight sections etc. This is where a carb cannot compete (guess I should throw in emissions here as well, not that I care about my carbon footprint...).

[CRF119]

You are right, i was only going for overall HP. Other advantage is easy tuning.

[Crasherfromwayback]

I was a told by a engine builder and tuner that a two stroke will always make more power using a carby anyway. He used to build and tune the old 2 stroke road racers at world class level. He also used to make the expansion chambers for them and do all engine mods. He said a good CR500 should make 100hp :) if it doesn't it was done wrong.



Can you ask him why then, it was Ito's NSR500 featuring fuel injection that was the first 500cc two stroke GP bike to go over 200mph?

Also, a CR500 will probably never do 100hp, purely because they'll only rev to around 7500rpm without flying apart. 80 maybe. But they sure as hell won't last long.

[avgas]

Also, a CR500 will probably never do 100hp, purely because they'll only rev to around 7500rpm without flying apart. 80 maybe. But they sure as hell won't last long.
My RG150 had 34 at the wheel after some boffin went nuts with it. But your right. It only lasted another 5,000 km then exploded.
Big end bearing came out like finely crushed flour. Piston rings were almost non-existent. Conrod had cool 15 degree bend.

But I am still looking for my 1L 2T...... someday

[Crasherfromwayback]

My RG150 had 34 at the wheel after some boffin went nuts with it. But your right. It only lasted another 5,000 km then exploded.
Big end bearing came out like finely crushed flour. Piston rings were almost non-existent. Conrod had cool 15 degree bend.

But I am still looking for my 1L 2T...... someday

Hahaha...yep. My 92 Honda RS250 did 82hp, but was hungry for parts when tuned like that, and revved to 12000rpm. But a big single like a 500 two stroke, has a really long stroke and they hate revving. When I road raced KX500's, I put a piston in it every time I raced it, as they used to start cracking pretty early.

[Reckless]

Looks like its here and waiting they prob have want to sell a few 350's before they hit the market with the next new development?
Heard they have been working with Rotax for quite some time on this.
Waste of time doing all the 350 MX and Exc stuff if smokers might come back and blow everything else away.
They probably can be fairly confident that no one else of any consequence is putting any time into 2smoke development so why not sell as many 4 strokes as you can while you can! Especially when The 300 exc is the biggest selling 2 stroke in the market and they pretty much have the smoker market to themselves. There's no pressure on them to bring new stuff in at all.



Quote from Rob Twyerould, technical guy for KTM Australia, taken from the July issue of Australasian Dirt Bike:

"There is definitely a well-developed prototype at KTM, but they are waiting for the next round of emission restrictions to be announced before pushing forward.

"KTM has developed and patented it's own mechanical fuel pump system and a very compact oil delivery system to the bottom-end bearings, and the whole bike works really well.

"While there are some reasonable performance improvements, the real advantages of the system are in emissions and fuel economy. So the motivation for bringing to market will only come with the new emission targets."


From what is said above does it mean no more mixing fuel as the bottom and has separate oil delivery thats not a real 2 stroke??

He talks evasively about 2 strokes at about 4:30sec mark in this Vid.

<iframe width="420" height="315" src="http://www.youtube.com/embed/UahY0D9Eivw" frameborder="0" allowfullscreen></iframe>

[george formby]

Hahaha...yep. My 92 Honda RS250 did 82hp, but was hungry for parts when tuned like that, and revved to 12000rpm. But a big single like a 500 two stroke, has a really long stroke and they hate revving. When I road raced KX500's, I put a piston in it every time I raced it, as they used to start cracking pretty early.

Reading stuff like this is really putting a damper on my foray into elderly 2t's. Ooh well, might as well feel the fear anyway & continue wrestling the green ba$tard.

[Crasherfromwayback]

Reading stuff like this is really putting a damper on my foray into elderly 2t's. Ooh well, might as well feel the fear anyway & continue wrestling the green ba$tard.

They're all good mate. You can get a whole season or so out of a piston/ring assembly on a big bore two stroke moto-x bike when riding in the dirt. It's just when you gear 'em to the moon and rev the tits off it all day thing start to go bad quickly!

[george formby]

They're all good mate. You can get a whole season or so out of a piston/ring assembly on a big bore two stroke moto-x bike when riding in the dirt. It's just when you gear 'em to the moon and rev the tits off it all day thing start to go bad quickly!

Sminky. Looks like a new piston anyway & the bike is riding me mostly. Bet it's not as easy to whip the pipe of the Ossa.

[CRF119]

From what is said above does it mean no more mixing fuel as the bottom and has separate oil delivery thats not a real 2 stroke??

Im guessing as the air flows through the crank it picks up some of that oil and that will be its lube. Like jet skis do......