We need pictures of the mod, don't really understand how what you did is changing the timing.
Does changing the timing effect the operation of the engine off of idle?
thks

 

have a look at the rotor..
there is a 2mm thick lug on it..that triggers the ignition.. pick up sits in sidecover..
rotate the engine.. that strip hits the pick up at some stage.. now make that strip 3mm longer..on the side that hits the pick up first..not the leaving edge
or.. if you want..take the key out.. and try it without welding, just turn the rotor 3mm should work too...at least for a short while

 

Hello Bernie and welcome to the forums!
It sounds like you know a lot about these bikes! KLX gurus are most welcome here

Your post is one of the most interesting I have read on the board for a long time. The ignition timing has been an issue for awhile and a lot of people have looked at it in an attempt to gain more power. So far, I dont think anyone has been successful.

It sounds VERY interesting what you are proposing. A walkthrough of this mod with pictures would be very very nice!

Also, you are from Australia, isnt the Australian KLX250 different from the KLX250 we get in the rest of the world? I seem to remember there being differences, specifically when it comes to ignition timing? Would this mod work on bikes outside of Australia I wonder?

I myself got an EFI KLX250, would EFI have any implications for such a mod? What about big bore kits?

Lots of questions I know, but this was an interesting post you made that opened up for a lot of things.

 

I think I understand what he's done, but would still like to see some photos, and confirm that Bernie's bike is the same as the KLX250S we all know. (I think it is)

And I just happen to have an extra rotor



Did your rotor look like this before you welded the extra piece on it Bernie?



Not sure where the 15mm comes into play..


How about moving the pickup 3mm? Someone in Japan did it on a D-Tracker




..

 

the 15mm is a rough measurement..there is heaps of room to weld..the 3mm is more important..
and yes, if there is room for the pick up to move..do that..

fact is, the R versions have a different advance timing... and that makes the difference...

but as said before, it should also be ok without the key and the rotor/flywheel is turned by 3mm (at the outside diameter) and then tightened up.
I did this mod in Germany..was a kit we sold with carb needle (at that time I used a needle of a zzr600d1, which is no longer available..

I have no idea how the fuel injected bikes are..and i don't want to know..that why I bought 2 carb versions ;-)

I retired from my job at Kawasaki to live in Australia.. racing and development is very stressful ;-)
I did heaps of stuff.. mainly go fast things..or how to make them go fast.. KLX650R with 72hp... KX500 with 80hp.. did super x engines for ron lechien, jeff matiasevich, and several german top riders .
and the knowledge I pass on here.. is what I tested..for myself or even for companies, giving me i.e. their crap exhausts, just to have it on paper, that they are crap...

 

and to answer about big bore kits...
its the only way to gain safe power everywhere...
if the kit is a 100% working thing, that doesn't explode... (half seen some damaged engine pics here of a kit..nobody picked it..why it exploded..i could clearly see that the valves touched the piston pocket..and then it broke..) a so called green certified technician replied, valves do brake sometimes... I don't think so...
I have a KLE500... built it in 92.. implanted half a ZZR1100 engine.. result 74hp... and only original Kawasaki parts used...
so..300ccm seems to be the way to go.. not sure if I will get a kit..cos then my son (he is 14) wants it too...

 

Oh the big bore kits have been proven over and over again on this board. There is even one guy with 100k kilometers on his KLX351 I believe. What I ment by my question is, would the ignition timing mod you describe work with a big bore kit as well?

Currently, the best way to get power is to get the KLX351 kit + webcams. Dynos usually put those bikes at around 32bhp at the wheel compared to 18~ of the stock bike. What would happen if you did KLX351 kit, webcams + ignition timing mod? Would it mean even more power for this bike?

My knowledge on the area is very small, I just read a lot on what other people do and then try to replicate it. It has worked pretty well so far, managed to install a OEM 292cc Kawa cylinder and a EFI piggyback controller to add more fuel....still looking for more power though, just because its fun to mod the bike!

I wonder, are there still people in Germany who modify these bikes? Generally, these bikes dont seem to be very popular in Europe and I find myself ordering expensive parts from America constantly because nobody here makes any aftermarket parts.

 

I got close to 30hp just with carb mods and timing in the 250... in early 90's was no big bore kit around...and the customer gave us his rotor, got a needle back and the rotor modified and ready to put in..cheap hp gain and no fiddeling around.
with a 350 kit and cams, carby around 36mm .. close to 40hp shouldn't be a problem . and ignition and timing can and will improve any engine.
some of the early klx250 with kickstart.. were a pain to start... pick up clearance was the problem.. and who ever checked the timing of a few of the same models..how accurate is the factory setting ? even if the timing marks line up proper, doesn't mean the TDC is marked 100%..

 

RayCour added timing and dyno tested with no positive results -

https://www.kawasakiforums.com/forum...x-37214/page2/

Thoughts?

 

they changed the advance curves..but not the static timing. an advance curve is only interesting below 5000rpm.. after that the static timing makes the change, not the advance curve.