Do you want more power? come in.

[robinyu]

Hi, I am RobinYu from china BeiJing with poor English. have a 2014 ST1300. I do some modification to my ST, let me show you.

this is the airbox, I cut it like this:


this part is removed.


compare before cut and after cut:



the original air intake is very small. just expand it as big as you can.

you will get more power, but maybe less fuel mileage.

It can not be undo, so, you have to buy a new airbox if you want original size.


after cut the airbox, you turn the throttle very small angle, bike will accelerate more.

 

[bdalameda]

Hi RobinYu

Your English is fine. I don't wish to sound negative but this kind of modification will ruin the power band and throttle response and make quite a howling sound. Also the fuel injection will enrichen the fuel mixture and the fuel economy will suffer. Without an exhaust improvement this is a waste of time. Doubtful if this will improve anything. Sorry to sound so negative but I have seen these kinds of modifications so many times and about 95% of the time do not work other than make more noise and ruin the throttle response.

 

[Larry Fine]

Robin, your English is not perfect, but it is good enough to understand.

 

[robinyu]

another modification, a bigger throttle handle core, same angle more throttle opening.

 

[robinyu]

Hi RobinYu

This will ruin the power band and throttle response and make quite a howling sound. Also the fuel injection will enrichen the fuel mixture and the fuel economy will suffer. Without an exhaust improvement this is a waste of time. Doubtful if this will improve anything. Sorry to sound so negative but I have seen these kinds of modifications so many times and about 95% of the time do not work other than make more noise and ruin the throttle response. Sometimes people think that more noise means more power.

I do the modification and feel a lot of difference, maybe you should try it. I think it maybe the same as a KN filter, but the filtration effect is much better than KN.

 

[heffly]

I think you need Honda CBR 1000....lol. ride safe

 

[bdalameda]

This will be interesting!? Have fun RobinYu!!

 

[Igofar]

I do the modification and feel a lot of difference, maybe you should try it. I think it maybe the same as a KN filter, but the filtration effect is much better than KN.

What your not considering is you've removed the one piece that directs the air into the airbox!
Enlarging the hole may not do anything but make more noise, hurt your mpg, and make the bike run leaner and very hot.
Your ECM will not be able to adjust enough to make up for the air flow.
Its just a guess, but your probably feeling just a placebo effect, kind of like Harley Davidson riders think they have more power because their pipes are louder, when in fact, open straight pipes loose a lot of horse power etc.
I would suggest purchasing a new airbox and putting it back to the stock configuration if you want the bike to run better and last longer.

 

[Upt' North]

Interesting work Robin, not heard of anyone trying it before although airbox mods work well on other bikes, so why not.
Keep us all posted, nice to have fresh subjects to read.
Upt'North.

 

[Whooshka]

Airbox mods can help if done correctly. Have done plenty of them myself. Some bikes react well to them, others not. RobinYu good for you for trying. One never knows unless one tries. If you think it improves your bike then job well done. Don't let the negative comments dampen your spirit.

 

[dduelin]

Thanks for the suggestions and the pictures to explain the thought behind it. I'd like to offer that because the Honda programmed fuel injection system runs in a closed loop - taking data from the exhaust gas temperatures for cylinders 1 & 3 and 2 & 4 plus coolant temp and intake manifold pressure - it makes adjustments to the fuel/air mixture to run the precise mixture that Honda programmed into the ECM. This constant monitoring and adjusting of fuel to air defeats efforts to derive more power from modifications that allow more air flow and/or more fuel. Mods like this can't affect a rich or lean mixture so no potential harm is done. If the ST1300 from the factory had a very restrictive air intake system or exhaust system like many bikes do, but not the ST, the efforts to improve airflow could help some but it would take some before and after dynometer runs to quantify any improvements.

Efforts to gain more power make quantifiable improvements when the ECU fuel mapping is modified and we have had members attempt to do this with electronic black boxes like Bazaaz with mixed results. I think this is the way to go with a closed loop system. Of course, I'm responding to how the ST was sold in the USA and Europe. The Asian bikes might have a different ECU and different emission control systems.

I always like the deep roar of the ST1300's 360 degree crankshaft V-4 short vertical intake tract engine when flogging the bike and yet when ridden at a moderate pace it reverted to the quiet mild mannered Honda character. Mods like this might improve the intake sound.

 

[Erdoc48]

I recall my brother (who has a Gen 1 VMax) noted a lot of people on his VMax forum did mods to the air box (specifically made for performance by Yamaha) and by drilling holes, etc. actually degraded performance of the bike. Maybe a small gain at the top, but in the low and midrange, made things much worse. He never did and notes his bike runs flawlessly throughout the rpm range.

Interesting for cars as well. In many cases, cold air intakes give more sound on acceleration, but no substantial performance benefit.

 

[SMSW]

Hi Robin, Were you to post dyno runs (graphs of horsepower made at different rpm's) you would silence the skeptics. Anything short of that will not convince most of the guys on this forum. Well, I'd think that say a statistically meaningful sample of runs down a drag strip against a stock bike might convince them.

The ST has such a well designed and complex motor that it is difficult to improve its performance significantly with easy mods, like, say early Guzzi's or early Harley's. Those were comparatively old designs that responded well to modifications. Reread @dduelin's post.

 

[diferg]

Hello Robin Yu! Welcome from south east Georgia. Your ideas are interesting, I am curious to see more.

 

[Whooshka]

And then sometimes gains are not measured in numbers only. The objective is not always pure HP increase. If the bike "feels better", then case closed. How many here use max performance all the time?


I never understood why so many on this site bash anyone who tries something different.

 

[ST-Traveler]

If you want understand how to get more power you might ask how Honda took the exact same engine and reduced the power.
This may help you understand how to increase power.

HP specs:
Honda CTX 1300 =83 hp
Honda ST 1300= 117 hp

I don't think they modified the air-box, but I could be wrong.

 

[Larry Fine]

I never understood why so many on this site bash anyone who tries something different.

In my humble opinion, not all critiquing and opining is bashing. The above responses seemed intent on being informative.

 

[dwalby]

I never understood why so many on this site bash anyone who tries something different.

Agree with Larry's comment that its not necessarily bashing, just giving honest feedback.

Regarding the 'tries something different' angle, if given the choice between a team of professional engineers who design bikes for a living using millions of dollars of test equipment and a guy on the Internet with a Dremel tool, I'm going to tend to favor the engineering team. Not saying its impossible for the guy with the Dremel tool to be onto something, but its not likely either. And, just because its 'different' doesn't imply its necessarily better. Honda engineers know how to make a hole bigger too, yet they chose not to, there's probably a sound reason behind that decision.

Haven't heard it mentioned much in years, but in the old days it was usually a case of "I'm just removing all the restrictions caused by EPA regulations, so it will run better" even though motorcycles have never been tested for emissions in California, ever. It didn't seem to work all that well in the carbureted days, and in the EFI days its even less likely to improve things.

 

[Larry Fine]

Honda engineers know how to make a hole bigger too, yet they chose not to, there's probably a sound reason behind that decision.

Pun intended?

Much advice against mods like this are based on actual experience. For example, the Nighthawk Forum is filled with threads about those who can't get their CV carbs to behave with removed airboxes to use pod-type air filters.

 

[v8-7]

its not bashing.. its educating .