more bhp!

Hello Guys:

It has been a while since I haven´t posted here :)

I have recently begun to practice supermotard, and I must say it is real fun!! If you recall, I have a 2003 EXC 450. The thing is, I would really like some more horsepower. (Although adequate for woods riding as is)

What would be a good way of achieving this, without spending too much money? The high comp piston (450) from KTM powerparts and a header and pipe? (Which ones? Can I just add the SX pipe to use it in the track, and obtain good gains? How much gains can I expect?) Or should I forget this piston and go for the 540cc kit (If possible).

I don´t want the bike to be unridable when I go out to the woods... although with the banning we have here in Spain, I am going out less and less, and going out more to the supermotard track

Thanks in advance,


easy, just get the 520 piston and cylinder and you got gobs more torque and some more power.

In car engines, a one point raise in compression is only good for about a 3% raise in HP. Go for more displacement and you'll get power gains at all RPM's.

Ride on


Finally I´m going for the 540 cc kit and the Doma complete exhaust (header and muffler) in steel. I talked to my dealer on the phone, and tomorrow I´m going to check out the Doma. What do you think of it? He told me there were two variants.



If you want to get more HP out of your KTM...Checkout These guys have their own shop, and are getting huge #'s out of their motors. They managed to get over 70hp out of a 520!!!!! I just sent my 520 in to them for the 540 kit and some valve work..let ya know how it works!!

Offroad riding in Spain, this for JamesKTM from Madrid.

I am from England, ride 2003 450 KTM, we have been to the Picos before, (2001) and hope to go back this Sept.

You mentioned about problems with bannining off-roading in Spain, any info on this woulkd be great, so as we can plan our trip.

Thanks ftheie and Dick:

Ftheie, I am from Spain, so it is a bit far from me, don´t know if I´ll make up to them on one tank :) but it is a very interesting site. I´ll tell you when I get my 540 transformation too.

Dick: it depends on where you are going to ride. If you speek Spanish, there is a good place to learn about legislation here If any of you speek it, tell me where you are going to ride, and I´ll translate it for you, as legislation is different in different states.



There's no replacement for displacement, 520cc or bigger, and some headwork. I think Kibblewhite is selling upgrade valves for the RFS. check I'm going to pull the head off of mine and put it on the flow bench in a month or two. I'm sure there's room for improvement. :)

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