I read about the clutch switch mod but haven’t tried it. Does it really give any more power?

What I heard is that it lets the engine rev up even more which means for me that it’s only useful at intensive accelerating. Am I right? Isn’t it harmful for the engine to rev up to 10 or 11k rpm?

 

Max horsepower is reached at around 8600 rpm. 10,000 over rev is possible and only risk in over rev is valve float and the 250 won't float the valves at 10,000, not sure about 11,000.

I don't know the full story on the clutch switch thing, but it seems to me that it had something to do with rev limiting in certain gears. If that's the case it might be allowing use of more of the present power, like a throttle restrictor. only so many revs.

 

I'd never heard of this "clutch switch mod" until this post. Apparently this is only on FI bikes, right? I've done the jumper wire on my '06 clutch/starter switch and sidestand switch, but obviously there's no ECU to influence. Still, I'm not seeing much advantage to revving this bike into the stratosphere.

I only googled this clutch switch thing and saw a couple of threads on it. Was the origin of this feature a safety device or what? I just picked up a new Z650 yesterday and was reading through the owner's manual. Good grief this bike is full of electronic fluff and stuff. For a guy who has owned a ton of bikes over a life time, this is the first FI bike with a computer I've ever owned.

That accident recording segment of the computer is interesting. I can see it now in court...so Mr. Smith, I see you were going 175 mph through that school zone when you crashed into the bus load of handicapped children, causing it to immediately burst into flames killing everyone. Is that right, Mr. Smith?

Big Brother riding with us...LOL!

 

After I posted this question I found some older posts and answers about this topic:

“I did this today, it makes a big difference, not managed to give it a good go yet, but I was hitting 60 in 4th and early 70s in 5th, then I ran out of road, it was just a quick test to make sure it wasn't going to break down on me.

Today i topped out at 75 max, now with the mod I reckon I will get 85/90 mph, without red lining it, It seems to have quite a good effect on 3rd and 4th with the extra revs”



“By-passing the clutch switch is great for 2nd, 3rd,4th and 5th gears but 6th still won't rev past 8000.”



“I've only owned my Klx for about 6wks. And have done this mod & it has made a huge difference. I can now get an indicated 90mph (on a good flat run) which is a genuine 82mph (on GPS) I would advise anybody to try this for the price of a split pin! It's about £500 quid cheaper than a power commander & faster”

For me it is a little bit difficult to believe that this simple modification can make such a big difference as these users mentioned...But I think I will give it a chance someday.

 

I can clear up this subject.

Recent dyno testing on Jeff Higgins monster motor build ( a 2018 KLX250S) has provided proof of the horrible truth.

So, long story made short:

A "power limiter" is built into the programming of each and every model year of EFI KLX250.. One known aspect of this detune is that it is designed to limit top speed by killing engine power above 7500 rpm in the upper gears (5th and 6th confirmed, lower gears unknown)..

Our European members (with years of experience with EFI KLX's) have known this since "day one" - it's "old news", and the information is readily available in here.. I can confirm the new EFI's are also affected.

The "Clutch Switch Mod" is a "workaround", created by Kawasaki. The clutch switch has multiple functions - one of which is to allow deactivation of the detune programming. By performing the mod, the "max performance" program is given persistent prevalence. Think of the mod as activating a performance fueling&ignition mapping/programming.

It should be considered a mandatory mod for all EFI KLX's.

 

Oh yes! This is the answer I was waiting for. I am wondering why there is no sticky thread about this mod (or is there?)

 

Go ask one of the moderators to have one put up. I did it for the cam chain tensioners. When it is something of this kind of value to all the EFI riders it's something they should do easily. Deej is one of the guys who can do it. Either KLXster or you can cut and copy KLXster's remarks and paste them into the opening post of the thread.

Just makes sense to do so.

Cheers,
Mark

 

Sneaky devils are always trying to spoil the fun with their little computer overlords watching and controlling everything we do that's fun...LOL! That was an interesting way to accomplish top speed limitations and an interesting way to delete it. Cool.

 

@Mateja , the EFI KLX's have historically had a "tiny" presence here. The few members with Euro KLX's (EFI's) are quite knowledgeable, but such knowledge has been rarely needed - UNTIL NOW !

Through my correspondence with Jeff Higgins ( "JH Motor Club" channel on Youtube) concerning his efforts to create a "monster" 2018 KLX250S build, we are learning much - And will learn much more in the future.

One such item: The stock injector will not support the engine as power levels approach 30hp. So far, the larger Beet injector seems to be functioning well ( as a replacement performance injector)..

I believe, as he works through the problems of tuning, he will end up with a 40hp KLX351.. I think he will hit 35hp now (with stock cams) if the fueling curve is fine tuned.

 

I want to try a 40hp KLX351 so bad.. .