The KTM RC390 thread | Page 3 | GTAMotorcycle.com

The KTM RC390 thread

You should at least read my post before going all dickish. I said same power and close physical dimensions. The physical dimensions difference would account for what it takes to reliably tolerate another 125cc. Canada isn't Europe, we have wide open spaces. A bigger engine can pull taller gearing for that. EU license regs don't dictate what works on another continent. How many of these bikes will actually see a race track? I make no mention of wanting KTM to emulate Japanese SS.

edit, what I was originally going for couple posts back was sure as CBR250 and Ninja250 have been upsized without big physical penalties the same will happen to RC390. So, in the interest of living in big sky country, I'd like to go straight to RC500 and skip RC390. kbythanx

We are a hick little country that equals barely a decent US state in numbers, with declining sales. Don't count on any CDN-specific models any more.
 
Apparently RS4 125 is 15 HP, but with race kit is 25 HP, RS125 is 28-34 HP. That is much closer than I expected. Any idea how they wring 25 HP out of a 4 stroke 125? That is quite impressive (and way more than the 13 that honda gets out of their 125).

With two strokes, the more gas/oil and air you flow, the faster they go.

There is a GREAT book written by Max Oxley called "Stealing Speed" about Walter Kaaden, the German rocket scientist that worked at Peenemunde on the V1/V2 rockets in WW2 and learned about exhaust resonance while working for Hitler. After the war, in East Germany, he applied this knowledge to 2-strokes with MZ and almost won the 125 World championship with 24 hp bikes. He discovered exhaust resonance.
His star rider, Ernst Degners, was set to win the championship when he defected and stole critical parts and knowledge and sold them to Suzuki, who then went on to produce the fastest 2 strokes in racing with this stolen technology with Degners, all the way into the middle 70s. Even Yamaha copied Kaaden's designs.
 
We are a hick little country that equals barely a decent US state in numbers, with declining sales. Don't count on any CDN-specific models any more.

:) Thanks for taking the time to address my concerns. The Ninja 300, for example, is a better tool for this country than the Ninja 250. Probably the Ninja 300 didn't come about because of Canadian market forces but there you go. All I've said all along is that I would prefer the Ninja 300 version of RC 390 rather that the Ninja 250 version if you can connect the dots.
 
With two strokes, the more gas/oil and air you flow, the faster they go.

There is a GREAT book written by Max Oxley called "Stealing Speed" about Walter Kaaden, the German rocket scientist that worked at Peenemunde on the V1/V2 rockets in WW2 and learned about exhaust resonance while working for Hitler. After the war, in East Germany, he applied this knowledge to 2-strokes with MZ and almost won the 125 World championship with 24 hp bikes. He discovered exhaust resonance.
His star rider, Ernst Degners, was set to win the championship when he defected and stole critical parts and knowledge and sold them to Suzuki, who then went on to produce the fastest 2 strokes in racing with this stolen technology with Degners, all the way into the middle 70s. Even Yamaha copied Kaaden's designs.

The two stroke makes sense to me, getting 25 hp from a 4 stroke 125 seems much harder. That's more hp than a honda CBR250R at half the displacement.
 
The two stroke makes sense to me, getting 25 hp from a 4 stroke 125 seems much harder. That's more hp than a honda CBR250R at half the displacement.
My guess is the race kit version has fewer emissions devices, probably revs higher (reduced reliability), and probably has very aggressive timing. I'm not the one to answer, though. I've heard you can get crazy power out of tiny engines if you don't expect them to last long lol.

Don't the Hondas both take regular gas while the Aprilia runs premium?
 
The two stroke makes sense to me, getting 25 hp from a 4 stroke 125 seems much harder. That's more hp than a honda CBR250R at half the displacement.

The CBR250 engine is very mildly tuned.

25 hp from a 125 4-stroke single is like 120 hp from a 600 4-cylinder ... that's high specific output, achieved with much higher revs, but not outside the realm of plausibility.

Long-term durability would be in question at that level. A 125 has to be designed to run wide open maximum revs continuously. Modern 600 fours have a redline near 15,000 rpm, a cbr125 is near 11,000 even though the cylinder is a little smaller.
 
The two stroke makes sense to me, getting 25 hp from a 4 stroke 125 seems much harder. That's more hp than a honda CBR250R at half the displacement.

Moto3 engines get 50hp from 250cc, but they are limited in injection velocity and only a single cylinder.

The CBR 250R is not the most stellar 250 engine.
 
:) Thanks for taking the time to address my concerns. The Ninja 300, for example, is a better tool for this country than the Ninja 250. Probably the Ninja 300 didn't come about because of Canadian market forces but there you go. All I've said all along is that I would prefer the Ninja 300 version of RC 390 rather that the Ninja 250 version if you can connect the dots.

? The ninja 300 has been here since 2013.
 
? The ninja 300 has been here since 2013.

And?

edit again dammit, I can see where you probably misread my post. are you multi tasking?
 
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Long-term durability would be in question at that level. A 125 has to be designed to run wide open maximum revs continuously. Modern 600 fours have a redline near 15,000 rpm, a cbr125 is near 11,000 even though the cylinder is a little smaller.

Yeah but they just go and go. Ninja 300 redline is 13K and the engines are tanks. This was all just racing fantasy piston speeds 20 years ago.
 

It's hard to comprehend your writing.

The Ninja 300 came about as a quick way for Kawasaki to exceed CBR250 torque for the Euro/US market. Similar to the 636 to compete with the other 600s. If they don't race it, it doesn't matter if they exceed 600cc. They do sell the engine as 250 still in some Asian markets. Since the difference is just stroke, it's just a different crank.

Yamaha is supposed to announce the Europe/US version of the R25, which is rumored to be 300 in some markets, and 350 in North America under the RD350 badge.

However, I have no idea why the 400 segment has been dropped. They did make a Ninja 400 for Canada, but sales were poor.
 
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It's hard to comprehend your writing.

The Ninja 300 came about as a quick way for Kawasaki to exceed CBR250 torque for the Euro/US market. Similar to the 636 to compete with the other 600s. If they don't race it, it doesn't matter if they exceed 600cc. They do sell the engine as 250 still in some Asian markets.

Yamaha is supposed to announce the Europe/US version of the R25, which is rumored to be 300 in some markets, and 350 in North America under the RD350 badge.

It (Ninja300)came about because progress. It's a better bike but retains the core of of the original. It's conceivable that someday the RC390 might be superseded by something a little better/bigger but well shy of the 690 Brian P. mentioned. That's a whole other class. I want the superseded version of the RC390 but I'm already sorry I mentioned that.
 
The power output of the 390 engine is constrained by wanting to stay within a licensing class in Europe. Given that Europe will be their main market, it's only going to change if the legal requirements change - or if they opt for a different model in North America, and given KTM's relatively tiny worldwide production volume and even tinier street-bike presence, that's highly unlikely. They will want to make the same bike worldwide.

Honda and Yamaha are big enough that they can opt out of that sort of strategy.

IF the RC390 is successful, the next step is an RC690 by translating the 690 Duke, just like the RC390 came about by translating the 390 Duke. But it will only happen if the 390 is successful ...

BTW it will be dirt cheap for KTM to produce an RC200 and RC125 if they want to, because the 125, 200, and 390 Dukes are all the same except for the engine, so they just have to drop the already-developed 200 or 125 engines into the already-developed RC390 chassis.
 
RC390 has a permanent duck face. Can't unsee
 
The power output of the 390 engine is constrained by wanting to stay within a licensing class in Europe. Given that Europe will be their main market, it's only going to change if the legal requirements change - or if they opt for a different model in North America, and given KTM's relatively tiny worldwide production volume and even tinier street-bike presence, that's highly unlikely. They will want to make the same bike worldwide.

Honda and Yamaha are big enough that they can opt out of that sort of strategy.

IF the RC390 is successful, the next step is an RC690 by translating the 690 Duke, just like the RC390 came about by translating the 390 Duke. But it will only happen if the 390 is successful ...

BTW it will be dirt cheap for KTM to produce an RC200 and RC125 if they want to, because the 125, 200, and 390 Dukes are all the same except for the engine, so they just have to drop the already-developed 200 or 125 engines into the already-developed RC390 chassis.


KTM is not so tiny anymore, sales were up almost 30% for 2014. Those power restrictions are all ECU chip based, so switching markets is just another chip.
Given the huge sales of small bikes worldwide and the price of the RC390, they will sell a poo load.

There is a huge potential market in not making boring small bikes.
 
Exactly.

Sorta get the hype around the 400cc class, but I'd much rather have a grey market 400cc '90s race replica over this any day of the week.

Depends. If you want to stare at it in your garage, ok, if you want to ride it, 90s race replicas are just that "replicas", and crap by modern standards. People romaticize 30 year old bikes, but 30 year old suspensions, brakes, frames and carbs are mediocre.

KTM styling has always been about distinction, as opposed to Triumph, which is a Japanese bike built in England.
 
Nobody's talked about a supercharger (not dragster style but better tech) for the RC390 yet. That would liven things up.
 
Depends. If you want to stare at it in your garage, ok, if you want to ride it, 90s race replicas are just that "replicas", and crap by modern standards. People romaticize 30 year old bikes, but 30 year old suspensions, brakes, frames and carbs are mediocre.
I seem to hold my own on a '87 TZR250 and '86 rg gamma. I ride pretty much every warm night with a bunch of newer gen 600cc - 1000cc bikes and I'm usually mid to front of the pack. Somebody will always have better equipment, it's what you do with it. Most of us mere mortals wouldn't know the difference of crap suspension, frames and brakes anyway.

Some of the late 80's and 90's build quality was outstanding. I know BMW S1000R and Ducati owners that's had as much bike down time as I have. The difference is I have to fix my bike, where as they are at the mercy of the dealer to fix theirs.

I'd be happy with a stock set-up on a RVF400 or ZXR400. I wonder how a shoot out between those and the KTM RC390 would go?

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kawasaki-zxr-400_2.jpg
 

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