Electronic Power Control on a 640sm

[kroosn]

Hey i was running through the workshop manual and came across the epc (electronic power control) which limits the acceleration in 2nd and 3rd on my bike (2005 ktm 640sm). just wondering if anyone has had a go at bypassing it im sure someone must have and is it a good or bad idea. it doesnt seem too hard. below is the description of it on from the workshop manual. anyhow have fun guys.

Kroosn

http://members.iinet.net.au/~robertgbailey/Clipboard01.jpg

[Wobbly]

At a guess I'd say plug the pressure line that feeds it? Or replace it with a FCR41 :snigger:

[kroosn]

firstly i just thought that would be the easiest way too, but now im heading towards just pulling off the electrical connector on the solenoid so it cant open ;) i was just wondering if anyone has done it. also surely its only to keep the wheels down or could it help save the drive train?

[Wobbly]

Sounds like a nanny device to me :) But just adds to the argument that cv carbs are evil ;)

[discobob]

I really have no idea (but it is the internet -ie must be true) if you remove it / plug it then the slide will open quicker and may make it run like shit.

[Wobbly]

Which means you'll really want the FCR instead :lol2:

[d_kimo]

i just pulled it off my bike at the time that i played with the main jet ... seemed to go better ...

but then i put on the delorto carb off my 620 and it went a lot better again :) ... (a cheap option at half the price of an FCR and pretty well as good for gumbys)

[speaksgeek]

I've been wondering this myself. Hard to find any real info on the thumpertalk and KTMtalk forums. What's the likelyhood of any real damage being done by just unplugging it?

[Wobbly]

Bugger all - it just varies the ignition advance in relation to throttle position...

[voidifbroken]

Its a fun-limiting device which limits the rate-of-rise of the slide and hence throttle response in the lower gears :shock:

You really,really dont want it.

plenty of info on how to get rid of it on advrider.com :)

[SMC690]

Off with it!
The nasty piece of work it is..... :)

[dicky]

The switch and solenoid open an air bypass when you hit full throttle in the low gears, leaning out the air/fuel mixture. This is to meet EPA rules and should be ditched as soon as possible.
You can disable it by unplugging the connector to the switch on the carby.
You can remove the switch, solenoid, hose and plug the hole in the top of the carby it you want to save a few grams.
Do not remove or plug the vent hose that goes to the airbox side of the carby, the carb will not work without it.
While you are at it, fit a good quality filter to the end of the vent hose, the original one is only good for straining budgies and will let a lot of nasty grit into the top end of the carby, enough to cause the slide to jam!

dicky.

[speaksgeek]

Sounds good, looks like I'm going to try unplugging it. Not too worried about the extra few grams though - I reckon I can handle the strain :P

[Daws]

That might be why I thought mine feels different at full throttle in the lower gears - I just assumed it was my crappy riding.

I'm off my garage with a beer on an EPC hunting expedition.

[speaksgeek]

I've unplugged it, done one commute, and it does feel a bit more pull in 2nd and third I think, but it's not mind blowing. Better off than on I suppose.

[Daws]

Unplugged mine - I THINK it feels better, seems like the front wants to rise a bit easier. Would like to confirm it on the Dyno.

[Muzzard]

Put the front wheel in the gutter at 90 degrees to the kerb, lock up the brake and roll it on in 2nd...
Does it do a better burnout? :lol:

[voidifbroken]

You wont see the results on a dyno (no more power), just better response.

My experiences on throttle response.

My '03 640SM was 'unrestricted' by fcukwit retards (Klemzig suzuki, adelaide) and I had crap throttle response until I put an FCR on. I mean really bad response, big delay on opening throttle,bad chugging at low revs.

My '06 640ADV was unrestricted by professionals (Prorider) and the difference is night and day, not as good as an FCR but WAY,WAY better than the SM.

[speaksgeek]

Ahhhhh, sounds like a great idea. Full throttle stationary 2nd gear burnouts. :-) Seems a bit tame, why not in 3rd?

I definately notice the increased rush in 2nd and 3rd now, at the top of the rev range.

[voidifbroken]

Next step, drill the slide and cut the spring :shock:

Sounds scary but makes it a bit better again :)




Assuming you can afford a 3mm drill bit and a pair of wire cutters :D