You guys may want to pepper all the other vids on that channel with posts asking about whether they re-fueled that bike after plate removal..

 

I have left another comment. Lets hope it gets a response.

This is too important to "just let go" - That "after plate removal" WOT afr curve is not all that bad, and is likely not dangerous.

This could open the door for every single owner to easily ( and for free ) regain a normal power curve ( therefore, significant power increases ) for the KLX300.

 

Folks, I have to apologize - perhaps I did not give this the attention it deserved, but now I have.

Viewed the vid on a large screen and watched the AFR data in real time ( bottom right on the dyno screen ) ...

I am now convinced that they DID NOT refuel the bike after plate removal. No dyno tuner would allow WOT AFR to reach close to 14:1, as is the case, as shown in real time, during the run.

While the resulting WOT fueling is not optimal, it should NOT be dangerous to the engine.

Perhaps a slight spoofing of the IAT is called for - In order to bring AFR down to 13 or lower ( but such could also affect MPG during "regular operations".. )

CAVEAT: This plate removal, without refueling, should be the first mod on a stock bike. Do not mod the intake or exhaust tract in any way - both must be kept stock . Any other mods to the intake or exhaust tract would create even leaner WOT fueling - likely dangerously lean. A tuner with proper settings/setup will be required for any further modding.

 

I'm running an EJK with no:

ECU controlled secondary throttle plate
ECU controlled primary throttle spring

Although the engine runs fine and the on/off throttle response is instantaneous, it seems to be running rich because the gas mileage decreased significantly and there's some black fluff accumulating on the exhaust tuning rings. When I can find the time, I'll need to get it dyno tuned. I use it every day for work, so that'll be a while. I might try leaning the settings just a little bit and see what happens.

 

I've tried to post the response I got from Best Dual Sport Bikes to no avail --- this is the fourth try. There were no fueling changes prior to or after removing the secondary throttle plate - the dyno run was with just the secondary throttle plate removed. "You can just to the plate by itself. You can do the slits in the stock exhaust and even the small air box mods without any extra fuel needed. I am working on ECU re-programming, but that will be awhile. Go ahead and do the plate and enjoy."

 

Ok, then the issue of whether, or not, there was refueling after plate removal is resolved !

ALL owners of stock KLX300's should remove the secondary throttle plate ASAP.

However, contrary to the response given above, I do not recommend ANY mods to the stock intake and exhaust tract, as the WOT AFR is already reaching close to 14:1 and any such mods would ( if effective) cause further leaning of the WOT AFR.

I certainly do not condone their recommended barbaric mutilation of the stock muffler with a damned grinder. Creating "***** nilly" alternate pathways for exhaust gasses is sheer lunacy. Perhaps they should show a "before and after" dyno of this "mod" so that peeps can decide for themselves whether or not to destroy their muffler.




Sidebar: This is a very exciting development in KLX300 performance. If EJK (etc) can develop settings for a "secondary delete" + lidless + Q4 - we could be looking at a quick and easy pathway of mods/recipes that take the engine up to 27-28 hp .

 

I have added a KLX300 section and this info to my stickie : https://www.kawasakiforums.com/forum...rations-44444/

 

This is another video from Best Dirt Bikes that is the only WOT and half throttle dyno runs I've seen on a stock bike set up to try to duplicate the weight of the bike and rider with stock tires. It would be good to see another dyno run at half throttle with the secondary throttle plate removed to see if the gain in midrange is similar and to see what the AFR's are..

 

Well more data is always good.

I agree with "Baldy" on the 1/2 throttle run - specifically that the ECM is running closed loop to the 7200 rpm mark as AFR's are staying very close to stoich. So, this would not change with a plate delete ( once ridden enough for the trims to "set in" and create a "new normal" for part throttle fueling in closed loop. )
IMO on the 1/2 throttle run, after 7200 rpm, the open loop fueling would rise, from stock, only to 13 or so ( with a plate delete) . Very acceptable ( but again, not quite optimal ) ..

Plate removal should be done ASAP by all owners of stock KLX300's.

 

Update: I successfully removed the secondary throttle plate by tipping the TB near vertical while still inside the frame rails. My test ride seat of the pants dyno closely mirrored the dyno graph presented earlier in this thread. There was a noticeable difference in acceleration from just below 5000 rpm to 7200 rpm, where before there was a noticeable increase in power after 7200 rpm. It was very linear with no obvious change in acceleration rate through the 7200+ rpm range. I'm taking it on a 120 mile loop from McCall, ID to Riggins, up the Salmon River to French Crk then to Burgdorf and back to McCall tomorrow. It will be a good test of the secondary throttle plate removal on all around performance.

It was a good ride yesterday. The engine performed much more to my liking. It's still not a ball of fire but it pulls willingly from 3k on up. It doesn't respond to abrupt throttle opening like my 2007 KLX351 with the 36mm pumper carb, but then it doesn't have an accelerator pump either. I would guess that it's performance is much more like the KLX300R now -- quite acceptable.