Anybody else install a booster plug I did I really like it I don't know if they gave me any more horsepower but it does run better.
Booster plug
- Thread starter Marty Moose
- Start date
I looked into it. I don't really see how it can work properly. The device is said to offset your temperature reading to trick the bike into thinking it's colder out. Then, the bike will add more fuel to compensate for denser air. They are taking advantage of one of the base maps in the computer which adjust a fixed amount for temperature and elevation.
But the whole problem with this bike is that the closed-loop feedback from the O2 sensors makes it too lean and thus makes the bike "surgy" and causes hesitation. So, you start adding more fuel, it's going to see that it's running rich, and try to lean out the system in closed-loop, within a certain tolerance.
Their website makes little sense, for example:
In reality, the bike is in OPEN loop during high RPM and throttle openings. The O2 sensor has nothing to do with this. I don't know about you, but the bike is plenty fast for me. We are all simply seeking better rideability and smoothness around town.
So, there are 2 things that could happen here. You will notice a difference initially for maybe 100-200 miles until the ECU adapts to the added fuel and goes back to being lean. Or, the boosterplug has exceeded the adjustment limits of the closed loop adaptation, and you will get more fuel at low RPMs, and way too much fuel at high RPMs. The bike is already on the rich side at high RPMs, as a safety precaution to keep temperatures in check. If you look at power commander and rapid bike base maps, you will notice they actually remove fuel from the high RPM/throttle conditions for more power.
That's my take on it... I did a fair amount of research. Please post with your feedback in about 200 miles I'm very curious to see if you notice a difference.
edit: I recently purchased a RapidBike EVO unit and hope it is the right solution. The way it works is sending the ECU a fixed voltage from the O2 sensor wires. This makes the ECU think it's running at the perfect 14.7 ratio so it stops adjusting fuel ratio. The module then uses its own algorithm with inputs from the O2 sensor to tune the bike for a richer ratio. There's also the option to stop auto adjusting, which effectively eliminates the use of the O2 sensors and makes the bike open-loop.
But the whole problem with this bike is that the closed-loop feedback from the O2 sensors makes it too lean and thus makes the bike "surgy" and causes hesitation. So, you start adding more fuel, it's going to see that it's running rich, and try to lean out the system in closed-loop, within a certain tolerance.
Their website makes little sense, for example:
In reality, the bike is in OPEN loop during high RPM and throttle openings. The O2 sensor has nothing to do with this. I don't know about you, but the bike is plenty fast for me. We are all simply seeking better rideability and smoothness around town.
So, there are 2 things that could happen here. You will notice a difference initially for maybe 100-200 miles until the ECU adapts to the added fuel and goes back to being lean. Or, the boosterplug has exceeded the adjustment limits of the closed loop adaptation, and you will get more fuel at low RPMs, and way too much fuel at high RPMs. The bike is already on the rich side at high RPMs, as a safety precaution to keep temperatures in check. If you look at power commander and rapid bike base maps, you will notice they actually remove fuel from the high RPM/throttle conditions for more power.
That's my take on it... I did a fair amount of research. Please post with your feedback in about 200 miles I'm very curious to see if you notice a difference.
edit: I recently purchased a RapidBike EVO unit and hope it is the right solution. The way it works is sending the ECU a fixed voltage from the O2 sensor wires. This makes the ECU think it's running at the perfect 14.7 ratio so it stops adjusting fuel ratio. The module then uses its own algorithm with inputs from the O2 sensor to tune the bike for a richer ratio. There's also the option to stop auto adjusting, which effectively eliminates the use of the O2 sensors and makes the bike open-loop.
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I've probably put about 2000 miles on the bike since I installed it from sea level to 9000 feet bike does seem to run better in all situation I too was not looking for more horsepower just a better running motorcycle and for 120 dollars I took a chance on it and I'm happy with it although I do run and arrow slip on with it I appreciate all feedback on this issue.
I looked at the booster plug a while ago and have forgotten the specifics, but the gist is that it works during transitional periods: IE acceleration/deceleration - it's main thing is to smooth out surging. At steady state it's out of the loop.
Could you describe in more detail, how it runs better?
Could you describe in more detail, how it runs better?
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The bike seems to come off idol and return the idol much smoother than before no hesitations anywhere. before when I would pull up to a stop light the bike would almost die and it had a hesitation around a quarter throttle or so. Apparently the booster plug is pretty popular with the BMW guys they have the same issues as we do there's a lot of information on booster plugs website testimonials and such.
That sounds right - It richens the mixture in those transition periods before the O2 sensors overrule it. I don't really have an issue, but it seems like an inexpensive, unobtrusive fix for borderline cases.
Hi just fitted a second hand one from a Darvel as it was cheap on Ebay onto my 939 had to mod the connectors to fit but definitely a positive result for roll on roll off throttle control , Gone from a 5 out of 10 to a seven on smooth power delivery but would really love to have a full remap as it looks like it's mainly emissions control causing it to be a jerky SOB.
Hi, I am tuning in late on thread / discussion. Booster Plug VS the RapidBike EVO.
I just purchased a Booster plug in hope of smoothing out the erratic engine behavior. Sounds like it did made a slight to medium difference in the bike's erratic throttling.
What was the outcome from Installing the RapidBike EVO ?
Boltboysf.
I just purchased a Booster plug in hope of smoothing out the erratic engine behavior. Sounds like it did made a slight to medium difference in the bike's erratic throttling.
What was the outcome from Installing the RapidBike EVO ?
Boltboysf.
I installed a Booster Plug and noticed no difference at all in performance, though I didn't get as far as checking fuel consumption. I should say that my 2013 HS was not as bad on fuelling as some people experience, and my Ducati guru Carl told me the BP couldn't work anyway, so I took it off. Still trying to gild the lily, I got Carl to fit a RapidBike Easy for me and it may have done a little good but the most annoying feature of the motor (which otherwise I adore) remains, and that is the inbuilt boost of revs when I'm slowing on the over-run. They all do that says Carl...
Bottom line is that anyone in the UK who fancies trying a BoosterPlug can have mine!
Nick
Bottom line is that anyone in the UK who fancies trying a BoosterPlug can have mine!
Nick
Gatdammit ol' fella; how does your comment on shifting relate to the topic of Booster Plugs? Maybe it's just me that's confused? 
Nick
Nick
Joined Mar 2013
3K Posts | 161+
Naples, IT
I thought it related to "in built boost of revs on overrun" line. Maybe I misunderstood.
Booster Plug made my 2013 Hyperstrada using California pump premium 92 RON gas much easier to ride through slow to medium speed corners. The idle at near sea level where I live is about 200 RPM higher, which I feel has reduced engine braking at lower RPM's and downshifting with manual throttle blip is easier and smother, and roll-on has more power and is much smoother without the jerky power-on transition before. I used to have to feather the clutch through tight hairpins down to 2000 to 3000 RPM at throttle transitions to avoid a jumpy throttle-on. Now no more clutch feathering required, and much easier and more relaxing to ride tight twisty bumpy mountain roads. Also while holding steady light throttle holding a constant speed I used to shift to a higher gear to have less unsettling herky-jearky with the slightest throttle closing an reopening if not focusing closely. Now almost no herky-jercky and easy to stay in a proper gear ready to pass cars. Overall much more relaxing to ride.
I've done just 2 rides so far with the Booster Plug, first a very tight twisty mountain 55 mile loop requiring nearly 2 hours with many 25 mph turns and many down to about 15 - 20 mph, rarely getting over 50 mph, with a loss of 4.5 to 5% less gas mileage. Second ride was about 6 hours on the bike and 230 miles, with a variety of some very slow tight and rough road, and mostly on good roads and medium speeds, with a loss of 5% less gas mileage. I closely calculated my mileage with the bike's odometer and fuel required to carefully top up the tank both times. I think some of the mileage reduction is due to being more comfortable being aggressive and throttling harder in the corners. The improvement in throttle responce and easier corner handing is well worth the small mileage reduction.
I've done just 2 rides so far with the Booster Plug, first a very tight twisty mountain 55 mile loop requiring nearly 2 hours with many 25 mph turns and many down to about 15 - 20 mph, rarely getting over 50 mph, with a loss of 4.5 to 5% less gas mileage. Second ride was about 6 hours on the bike and 230 miles, with a variety of some very slow tight and rough road, and mostly on good roads and medium speeds, with a loss of 5% less gas mileage. I closely calculated my mileage with the bike's odometer and fuel required to carefully top up the tank both times. I think some of the mileage reduction is due to being more comfortable being aggressive and throttling harder in the corners. The improvement in throttle responce and easier corner handing is well worth the small mileage reduction.
Just curious to know if you tried the Touring map as a way to improve smoothness at low speed/revs? I guess it's not as macho as the Sports map, but boy does it improve the behaviour of the bike. Needless to say, all the horses are available with a few degrees more of twist-grip.
My problem was never with the throttle response (though sport is a little snappy on rough roads), it was more the rough and stumble power delivery down low. While not perfect, getting a better airbox lid / filter (Star.ace) and pairing it with a map from the Termignoni T800 smoothed things out enough that I can use power down low in 2nd on tight corners instead of needing to drop to 1st to keep the revs higher all of which contributes to less chassis upset and cleaner lines in tight turns. Perfect solution would be to buy a Rexxer and flash the thing with the help of a dyno, but this feels good enough for me and gas mileage seems decent still (35 - 40 mpg)
Joined Mar 2013
3K Posts | 161+
Naples, IT
Or adjust the sprocket size (smaller front or bigger rear). I went with a 14T front and it transforms the low end. Even more so with pipe, filter, tune. Gets you out of that urban speed bog zone much earlier. You theoretically lose top end, but I never enjoyed staying above 100 mph on this bike and don't miss whatever I lost. I can confirm it will still reach 140 indicated, if you're crazy. It does increase rpm target for cruising but not enough that it changed my riding style.
