Posts
2075
Joined
3/18/2017
Location
Boston, MA
US
Edited Date/Time
11/19/2017 8:15pm
So every year we get pretty detailed break downs of what each manufacturer has updated on their bike and what those changes will do to add hp. We saw with the yamaha when they changed the engine layout how they have the ram air, wrap around exhaust ...etc. Then with the honda we have full engine pictures like on the new 250 showing the downdraft intake, twin exhausts, twin cams, two intake/exhaust ports. I feel like since KTM hasn't really gone in any crazy new direction that we haven't gotten as detailed explanations of what is going on inside these engines to create so much hp. They use the old school dohc, standard exhaust/intake layouts on the 250 and sohc on the 450. How are they making so much more horsepower than everybody else while using the old school engine layouts. The new honda 250 is making way less hp and tq than every single other bike like 5 less the whole power curve until 10k rpm then it revs higher than all of them and pulls power longer.
The KTM/Husky on both their 250's and 450's are making way more horsepower than all other brands and they use the old school layouts with no downdraft, ram air, twin exhaust...none of that. They use the old school engine layouts like the Suzuki and Kawi. What is going on inside these engines to make them so much more powerful? I feel like it has not been explained as much in detail as the others so I really don't understand what their doing in there to gain all this hp. Can someone help me out and let me know what they're doing? KTM, Husky, Kawi, and Suzuki are all essentially using the same engine layouts apart from the Kawi/Suzuki having DOHC on their 450 models. Anyone? This has interested me for a while and I was very surprised when looking at the dyno's of the new 250s how with all the changes how much less hp the honda makes than every other bike until 10k rpm with the downdraft and twin exhausts. The KTM/Husky have used the same engine layouts the whole time along with what all of the other bikes all had at one point but yet they make by far the most hp, I don't get what their doing to get this and why other brands can't keep up although they have all had this same engine layout at one point or another or still do. Thanks.
The KTM/Husky on both their 250's and 450's are making way more horsepower than all other brands and they use the old school layouts with no downdraft, ram air, twin exhaust...none of that. They use the old school engine layouts like the Suzuki and Kawi. What is going on inside these engines to make them so much more powerful? I feel like it has not been explained as much in detail as the others so I really don't understand what their doing in there to gain all this hp. Can someone help me out and let me know what they're doing? KTM, Husky, Kawi, and Suzuki are all essentially using the same engine layouts apart from the Kawi/Suzuki having DOHC on their 450 models. Anyone? This has interested me for a while and I was very surprised when looking at the dyno's of the new 250s how with all the changes how much less hp the honda makes than every other bike until 10k rpm with the downdraft and twin exhausts. The KTM/Husky have used the same engine layouts the whole time along with what all of the other bikes all had at one point but yet they make by far the most hp, I don't get what their doing to get this and why other brands can't keep up although they have all had this same engine layout at one point or another or still do. Thanks.
The Shop
Anyways back to the question about the KTM/Husky engines someone has to know why with standard engine setups that we haven't heard about any ground breaking differences implemented yet they consistently make the most power of any bike year after year.
No one talks about the TM 250f but reading snippets online, that thing is powerful. Would love to see the Dyno of that with the others on the same dyno.
So straight intake port, finger followers, quality internals, best factory cylinder head that does not need porting.
There has to be much more than this adding to the huge hp numbers that we see every year but this definitely is a start. Especially seeing that they don't have ram air or anything very drastic it has to be very high quality internals but Im curious about the layout of those internals creating this hp seeing that they use the standard mx engine layout especially when looking from the outside. From the outside they look basically just like the Kawi or Suzuki where the Yamaha and Honda are very noticeable that there are big differences from the other brands. I do believe the KTM also uses a bridge box piston unlike the Suzuki which gives the Suzuki an old school engine braking feel vs the newer more freewheel feel of modern 4 strokes. Just trying to get the designs of these engines figured out because there isn't a ton of info out there about why they make such big numbers. Thanks guys.
^^Also wierd that the TM is never included in the tests and also never benched even if they actually test it.
Having ridden the 250f I think i would be up there with the other euros in power.
Pit Row
Having said that I think its a combination of things that make them really fast, 1 they are tighter tolerances and good quality parts so they don't break in as fast as Jap bikes
2 the bikes are light to begin with
3 its the way they put power to the ground they don't just spin the wheel they seem to really find traction and drive forward
And would you do a head to head vs this years winner in Jan?
Lastly, the ktm/husky make power for a few simple reasons.
1) larger bore shorter stroke than anyone else (until this year with Honda....current ktm engine based off the 2013 largely)
2) larger bore allows larger valves. The ktm has massive valves vs the other bikes (minus new Honda) close to japense 450s. Big valves coupled with a properly sized port for the valve means more air flow potential - which ktm has a very large port
3) finger followers. These have so many benefits it's hard to list them all. But it namely allows more aggressive cam profiles with more lift and ramp rate coupled with better valve train stability up to higher rpm
3b) huge camshaft vs japenese
4) the best parts money can buy, stock. The stock piston is a piece made by CP from billet, not forged but fully machined. It runs tight clearances piston to head and valve to piston. It's relatively high compression for a stock bike...more so than the jap bikes. The rods are plain bearing, prankl rods, with German skf bearings inside.
5)awesome stock exhaust system. On the dyno it's hard to beat...especially the header. Some people bolt on various pipes and swear it's better on track...good for them. Dyno says you should Stick with oem header and maybe a slip on...
6) oem mapping is very good... but that varies to your fuel and locale...
7) tuned intake tract/bellmouth
lastly ktm has spent time minimizing viscous drag losses via design internally as much as they can. This is worth a lot of power surprisingly on some bikes.
All in all after they shortened the rod for the 15.5/16 bike and upped the compression plus slightly different cam profiles, they turned the 13 engine into what it is now.. class leading on the dyno
Yamaha has spent huge time making a motor that FEELS fast vs one that makes most hp. It's actually a classic Yamaha engineering acheivement... their yz250 was never the most hp... but always considered the best spread of hp and delivery. Their r1 cross plane is another example of chasing more than just hp...
If ktm updates the 18.5 model to what it's rumored to be... the Japanese better start doing something serious.
Post a reply to: Ktm/Husky Hp