KLX 250 ( 300 ) camshaft mod by Marcelino
I think it's a bit of both. I have had from a DJ128 with/without lid, to a 124 with no lid, to a 132, and any range in needle from 3N to 5N. It doesn't run bad with any of those setups but the performance difference is there.
I'm with klxster, I have no idea about stock exhaust. I know there is an FMF quiet core some are running, but I doubt it's as quiet as stock.
I'm with klxster, I have no idea about stock exhaust. I know there is an FMF quiet core some are running, but I doubt it's as quiet as stock.
The KLX is extremely tolerant of wrong carb setups with goofy AFR's - Heck, I was lovin my bike when it was seeing 10:1 below 6.5K recently - what an eye opener when that dyno chart popped up !!! TRQ curve is now enhanced by changing the setup to get my current 12:1 to 13.5:1.. No comment on the AFR's dogma is creating out there - except to say that more and more are "going with the data" and leaving dogma behind..
I haven't been on this forum for ages, but thought it was worth mentioning that I reversed my 1/2 MCM (I only modded the inlet valve timing) recently.
I had been getting increasingly frustrated with the power characteristics over the last few rides. I had noticed more vibration at mid revs than I remembered and also that I never seemed to be in the right gear. I decided that I would unmod the KLX and sell it - maybe even buy a CRF250L!!!
After returning the bike to standard (except the clutch switch mod (EFI)) I had a ride out for a couple of hours. I expected it to feel flat and wheezy, but was shocked to find that the bike runs quite a bit smoother and does not need as many down-shifts on hills. The throttle response feels less abrupt but the bike actually pulls better. The power is also more linear, in respect to both throttle opening and revs. Tickover is more stable and I have been able to lower the tickover revs.
Since I did the 1/2 MCM I noticed about a 10% increase in fuel consumption. Hopefully it will go back to "normal" now.
Anyway, I'm quite happy with the bike now. Yes, it's shortcomings are very apparent compared to my enduro bike, but within it's limits it a nice bike for reliable, unstressed back lane tootling.
Maybe the Kawa engineers are not so daft after all?
I had been getting increasingly frustrated with the power characteristics over the last few rides. I had noticed more vibration at mid revs than I remembered and also that I never seemed to be in the right gear. I decided that I would unmod the KLX and sell it - maybe even buy a CRF250L!!!
After returning the bike to standard (except the clutch switch mod (EFI)) I had a ride out for a couple of hours. I expected it to feel flat and wheezy, but was shocked to find that the bike runs quite a bit smoother and does not need as many down-shifts on hills. The throttle response feels less abrupt but the bike actually pulls better. The power is also more linear, in respect to both throttle opening and revs. Tickover is more stable and I have been able to lower the tickover revs.
Since I did the 1/2 MCM I noticed about a 10% increase in fuel consumption. Hopefully it will go back to "normal" now.
Anyway, I'm quite happy with the bike now. Yes, it's shortcomings are very apparent compared to my enduro bike, but within it's limits it a nice bike for reliable, unstressed back lane tootling.
Maybe the Kawa engineers are not so daft after all?
Actually I'd say it's really important for anyone, not pleased with this mod, to speak up.. It was my first mod on a brand new KLX. It made a noticeable difference so I've never looked back..
Does anyone have pics of the stock cam position? I put the bike back to stock and put in a 126 DJ main. Bike bogs heavy. Starts and idles fine. I`m at 1000 feet asl. Should be rich if anything since it ran better with the stock main.
Also, is the front cam (towards the front of the bike) the exhaust cam? I suppose its possible I`m off on cam position although everything looks good. I checked rotation to ensure nothing was hitting lol.
Thanks
Also, is the front cam (towards the front of the bike) the exhaust cam? I suppose its possible I`m off on cam position although everything looks good. I checked rotation to ensure nothing was hitting lol.
Thanks
Does anyone have pics of the stock cam position? I put the bike back to stock and put in a 126 DJ main. Bike bogs heavy. Starts and idles fine. I`m at 1000 feet asl. Should be rich if anything since it ran better with the stock main.
Also, is the front cam (towards the front of the bike) the exhaust cam? I suppose its possible I`m off on cam position although everything looks good. I checked rotation to ensure nothing was hitting lol.
Thanks
Also, is the front cam (towards the front of the bike) the exhaust cam? I suppose its possible I`m off on cam position although everything looks good. I checked rotation to ensure nothing was hitting lol.
Thanks
The exhaust cam is most easily identified by the KACR as shown in the pictures. It's the only cam that has a spring on one end.
You can infer the stock cam locations from the pictures on the first post as well. If I were you, I'd mark the cam location where it sits now (similar to whats shown on post #1) and then change the cams bolts back to the right holes. Line up your marks within half a tooth the opposite direction of the procedure described at the start of this thread.
Your jetting is inline with mine (124 @ 1800 ASL). As KLXSTER pointed out, I'm probably pretty lean on the top end with that. Do you run an aftermarket exhaust or any airbox mods? What position is your needle and fuel screw?
No exhaust mod other than a wider straw. KDX snorkel clip in the middle position on the needle. Fuel screw is about 2 out. I'm thinking either I'm off on a cam or I need to open the carb


