Booster plug has anyone tried it?

I saw this in a topic on thumbertalk and someone was raving how it helped smooth out throttle response and fueling issues with there crf450l. I'm curious if anyone has tried it on the wr? I know they sell a kit for it. This would be a alternative to a programmer.

I have one but have not installed it yet.

Basically it tells the ECU that it is colder out than it really is and that richens up the fuel mixture a bit. Probably will help with some lean fueling near idle and low throttle but it also will add more fuel at WOT where the WRR runs a bit rich.

If you have a WRR with an O2 sensor then the system will begin to trim back the fuel once it sees it is running rich. I don't think any of the US models have an 02 sensor unless they were add for an Autotune type feature on a programmer.

Thanks for info, I’m trying to decided if I want to mod engine or not. The bike cuts out a bit when it’s cold but is better when warmed up. Some believe it is better to leave stock others think doing the engine mods helps. I don’t want the torque to change if I do engine mods. Seems like torque is better in a unmodded bike from what I’ve read.?

Iceburg7 wrote:

Thanks for info, I’m trying to decided if I want to mod engine or not. The bike cuts out a bit when it’s cold but is better when warmed up. Some believe it is better to leave stock others think doing the engine mods helps. I don’t want the torque to change if I do engine mods. Seems like torque is better in a unmodded bike from what I’ve read.?

Sort of depends on how you use the bike.

If you are doing a lot of trail riding I would change the gearing and then have the suspension setup (springs and revalve) for your riding weight and style.   I went to GoRace to have my suspension done but any competent suspension shop should be able to do something similar.

I have ran the gambit on engine mods except for an overbore motor.  My experience has been you can get it to pull harder and make a little bit more power at the higher revs with pulling the airbox door, aftermarket muffler (keep the stock header), and a Power Commander custom map.  But you will loose some of that low RPM part throttle grunt that you get with the stock EXUP.  For many this is a worthy trade but in my case I like the low rpm grunt with the EXUP for slower riding through the woods.  That and the RSM Clutch lever to open up the friction zone of the clutch for better control.

Right now I am pretty much back to stock except for a more open airbox, AIS removal, and a decatted stock muffler.  When the bike is cold there is a definite hesitation that goes away after 10 - 15 minutes of riding.  But since I like to play around with things and apparently have more money than brains I decided to go ahead and give the booster plug a shot.  I may get it put in this weekend if the weather holds up.

Let me know what you think of the booster plug , I’m curious if helps with the cold hesitation. I’m where your at on the bike. I think one of best mods is suspension and I want to have as much low end grunt as the bike will give for better trail riding. Sometimes contemplating a different bike with more low end torque, but like a lot of things the wr offers. Lol

Have you guys adjusted the CO setting first? This will give the bike more fuel at idle, and its totally free.

https://wr250rforum.forumotion.com/t3769-wr250-r-x-built-in-programmer

Also, adjusting the TPS can help with low end jerkiness

Jens - Thanks for bringing that up, I had forgot about that little feature. I have played around with the CO setting and yes it did make a difference. I believe I am +3 from the stock setting but it has been awhile. The bike runs pretty good after it is warmed up. I have changed my riding style a bit and really don’t notice any low speed throttle jerkiness anymore but that may be due to using the clutch more often in slow sections and leaving the bike in a higher gear.

Iceburg - you may want to follow Jens advice and play with the CO Setting first since it is free and it may get you what you are looking for.

Yes I will try that ,is there a good turtorial video on how to adjust CO?

Yeah, I cant access it from my work computer. Just search for "wr250r co adjust" or something like that.

Well I finally got around to installing my Booster Plug last weekend.

Install is pretty easy, you just unplug the harness from the Intake Air temp sensor - aft of the battery box on the LH side of the bike - you may need to remove a relay to get access. You then plug the bike harness into one end of the Booster plug harness and the other end plugs into the sensor. There is an external temp sensor that you want to run and anchor to the bike - I ran it forward and tie strapped to an existing cable on my bike. You just want to keep this sensor away from any source of heat on the bike like the radiator or the exhaust.

Started up the bike and it idled smoother and the cold start hesitation was gone when I jumped on it for a quick ride. Normally there is a 'hole' in the throttle response when my bike is cold that pretty much goes away after the bike is warmed up - 3~5 minutes of riding usually does the trick.

Throttle transitions seem smoother but don't expect any major power gains. The problem I have is that I have been working at our plant in Mexico for the last few months and typically only get home every couple of weekends which means I haven't been doing much riding on the WRR and my Butt Dyno is not calibrated at this point.

I will be home for the next couple of weeks and I will get out and do some more testing. Since the installation is pretty easy I think I will let my buddy connect it and disconnect it and not tell me if it is working or not as I ride some loops. He is an ex WRR owner and I will do the same for him so at the end of the day we should have some blind testing done and should be able to see if there really is a difference.

BTW my WRR is a 2012 model with 18,000 miles.

I have the air flapper and AIS removed along with a modified air box to improve airflow - IMHO don't mess with the airbox if you want to flow more air, just pull off the airbox door. Easier to do and put back to stock.

I am running a modified stock exhaust with the EXUP valve. Stock exhaust modification was removal of the catalytic converter from the system.

Keep me posted what you think of the booster plug and if you think it worth the mod.

Ok after a bit of delay (Open Heart Surgery in January) I finally got to spend some time with my WR250R with the Booster plug installed. My rating is a solid 'Meh'.

While it did significantly lessen the cold 'flat spot' it did completely eliminate it. However, the flat spot is completely gone once the bike reaches operating temp with and without the Booster plug so I really don't see an improvement for me unless I was doing a bunch of short rides with long breaks in between rides.

The downside is that I noticed a significant hit to my fuel economy - the low fuel light came on ~20 miles earlier that usual with my 3.1 gallon tank. Now to be honest I was playing around with a couple of 1090's and a 950SE at the time so I was probably a bit more aggressive on the throttle but at the same time I have not seen my low fuel light even come on that early in a ride.

So for now I think I am going to disconnect it and do some more riding to get a better feel if there is anything I am missing.