FE450 70d upgrades

570 conversion srsly tho idk ... I'd have a look at the suspension! Suspension work is a lot of fun!

Be specific and you can have loads of ideas.

Palle said:

Noone knows?
I thought some of you knew everything!

Click to expand...

It depends on what you are after. Ice racer, hill climber, rally, motard....? Peak HP, bottom torque, usability, maintenance schedule?

I have mostly gathered 570 info so I know that I like to use a 450 air boot and that a 450 ECU can give me more rpm.
You could get more and longer lift from a 570 cam, but I don't know if you want that as I don't know what type of characteristics you are after (and honestly I'm a bit short when calculating timings in a 4 stroke). There are other KTM cams that can be used, but which one I have no clue (I settled with the oem cam).
If you want a shorter intake to get more top performance you could have a look at the 570 boot as it have no tract.
I don't think headers are doing much of a difference in Hp. The "powerbombs" and what not are there to lower the dB, and as a side effect they might change the characteristics(?). Ljunggrens motor told me that they didn't see any hp increase with the akra header, but it's more lightweight and lowers the dB with 2dB (important when you compete). Doma has much thicker header and midpipe, but bigger is not always better. If you want to have a rally bike you can find examples of more straight pipes.
A head is always better after it's given a bit of love. No need to change the profile but to remove obvious imperfections can help. Then you can go full out and send it to a shop which will test it in the flow bench.

But really everything is doable as it's a 4 stroke. It's really up to what you want to do and how much you want to spend. Most "shake'n'bake" 70d tunes found on internet are from 570 engines.
You can convert to 570 (or most cc between 500 and 660 depending on what crank and cylinder you use).

Maybe you could find out what the Dakar teams are doing to their KTM 450s? But I guess the answer is "a bit of everything"..?

So yes there are for sure a lot of things you can do. But that answer is as vague as the question So what do you want to achieve? Maybe then other more knowledgeable members of this forum will give you better answer than mine?

If you compare differences for a 450 to the 570 one will see that they are more or less the same, apart from the obvious stroke and displacement difference.

The differences are:
Intake tract
A bit less lift and duration on the intake lobe
Rev limiter 10500 instead of 9800
570 has stronger clutch springs.

But the throttle body is the same ID, exhaust is the same, head in/out the same.

I seen that most 70d rally bikes have straighter underslung exhausts. Beneficial for both performance and heat. I also seen it on ice racers. So if you want to have better performance at the top range maybe that is the way to go. My impression is that the KTMs have a better nicer performance at top while the 70d feel more restricted. From what I understand it is due to all the bends in the exhaust (I learnt at my job that every 90 deg bend is equivalent in friction to 2 m pipe of the same dimension..). So you might be better of with a straighter exhaust?
But you should also re-map the ECU when you do big changes like that, so you might want to look into what options you have there. KTM tool, vortex/ignijet or something piggy back. If you start playing around maybe you could try the 570 air boot and/or cam? See if you can borrow that from someone so you can try. Both are easy to swap.

Prob a bit late for my response but it serves those searching for info.

Get 8 thou removed from the base of the barrel running the standard piston for approx 13:1 cr.

Run a 570 cam.

Run a piggy back tuner, remap or Vortex etc as you will need more fuel.

Open the airbox by either or both by cutting back the seat and/or the rad shrouds.

Straight through exhaust.

This has given me 58hp and totally useable power.

From here, head work, throttle body work etc.