A Mod To Help Keep Your Busa From "Over-Heating"

[Johnnnycheese]

I am not misleading people try it with a PC2 that you have 35's in the 100%  and not on the dyno on the track

[omgang]

Anybody else from a climate that's not hot wanna chime in??  

I'll bet you that if someone makes just the IAT relocation mod on a bike that typically overheats, and then rides in the same hot stop/go situations that his bike is still going to overheat.  You want to make the bet?  Relocating the IAT is not going to completley cure an overheating problem.

It doesn’t have to be very hot (90+) to get a Busa (or any other water cooled bike for that matter) to overheat.  Just let it sit and idle for 5 to 10 minutes and you’ll se the temp gage head towards “H”.  Every bike I've ever seen does not have a good enough radiator fan to keep it cool for very long.

Airflow through the radiator is what primarily cools the engine.  This is why the only guys who have fully cured overheating are the ones who put a 2nd fan on the radiator.

Good point:

I relocated the IAT sensor a few years ago to cure a problem of shitty/stumbling idle after hard running and then hitting traffic - stop lights, etc.  Two summers ago, while in Montana going through a long construction zone following a pilot car, my 'busa overheated and I had to pull over and wait for it to cool down before I could get it started again (this was after the IAT mod).  I replaced the plastic fan with a Muzzy's and have not seen the temp guage ever climb as high since.

So, the IAT mod definitely helped cure the issue of poor A/F ratio due to heat soak but the Muzzy fan solved the overheating problem.  I think both mods are worthwhile.

OM Gang

[JINKSTER]

It appears to me that Johnnycheese and I are basically looking at the same issue but from different ends...and where I'm trying to watch what I FEED my athlete???....Johnny seems to be addressing things from the bedpan end of the world. Hey...I owed him that.


Bottom line???....it appears that for some maybe I have mis-titled this thread...

"A Mod To  
HELP Keep Your Busa From Overheating"

But for me living in sunny south florida where HEAT is almost always an issue???....the title line fit just fine...check out some other threads where some of your very own Busa Brothers visited Daytona's Bike Week just a couple weeks ago and wound up nurse-maiding their overheating busa's as they desperately tried to escape the highly congested main street area....for hours...fender too fender...shoulder too shoulder...literally.

Also...I didn't buy my Busa with the intent of becoming a 1/4 mile master or a top-end speed legend...I'm just a street level sport rider who loves to go on weekender and week long Sport Touring trips...and I lusted after a Busa to become an extremely formidable "Hyper Sport Tourer"....that's my vision and that's my busa's mission...and for those of you who are left totally unawares???...and very much in contrast to popular thought and opinion???.....I find the most stunning thing to me about my new Busa is it's "Handling"...as this bike handles nothing like what it looks...it is extremely light on it's feet for it size and weight and shockingly???...is a scalpel in the curves as opposed to what one might believe based on it's massive appearance...and as a Street Level Hyper Sport Tourer???...located ihere n sunny south florida???...

RELIABILITY & OVERHEATING are always strong concerns.

That said???....Many of you are correct...and moving the IAT Sensor is just one of many great suggestions and mods that have been somewhat re-addressed here in this thread...and even Johnnys right...as JUST moving the IAT Sensor most likely won't "On It's Own" cure an overheating problem...but I still contend that this mod can, does and will "HELP" keep your busa from overheating under the same conditions as I encounter on a daily basis...and remember...this mod does help richen the AF mix and just that in and of itself helps keep the engine running a tad cooler so...IMNSHO???....it's still a D2mn good mod and well worth the $10 and 1 hours time to preform.

Also..sorry I opened up this apparent can of worms but the good news is???...we just uncovered a wealth of great info for all of us Busa Newbies...Self Included.  

L8R, Bill.

[CID]

So, the IAT mod definitely helped cure the issue of poor A/F ratio due to heat soak but the Muzzy fan solved the overheating problem. I think both mods are worthwhile.

 


While we're back to the subject at hand (over heating)....don't forget that ENGINE ICE is another big helper down here in Florida!

Plenty will argue that on merits of cost, but I've seen a real change in my bikes since I started using it a number of years ago.

[Busa@11K]

Also..sorry I opened up this apparent can of worms but the good news is???...we just uncovered a wealth of great info for all of us Busa Newbies...Self Included.  

Like others have said, you're info on moving the IAT sensor is A1 info.

It's just that there are a lot of super technical Busa experts on this board, so if there is anything "amiss" about the information it will be focused on.

Don't take it personally ... everyone can learn from the people who pick apart the technical aspects of the discussion.

[CID]

It's just that there are a lot of super technical Busa experts on this board, so if there is anything "amiss" about the information it will be focused on.

Yeah and now it's got everybody gun shy and now NO info on handy mods ever get posted anymore....pisses me off too.  


All these fastest, smartest fucks on this board and all I see is the turbo, bling-bling info anymore.

Used to be all the mods were shown in pics about once every couple months...now that the old members know them, they don't get out anymore and people get bitched at to 'search' for the info with a search engine that sucks ass.

Good to see shit back up on what used to be the 'technical hayabusa' board.

[BusaPwrd]

That was an excellent write up!!!!!! Please continue to do so in the future!!!!!    

[MATT_WRIGHT]

I am not misleading people try it with a PC2 that you have 35's in the 100%  and not on the dyno on the track

If you have a pc2 with 35's in it you have already maxxed out your stock fuel system at the top of your torque curve.  It won't enrichen ever.  Fast or slow.   You can't exceed 100% duty cycle on your injectors unless you have found a new trick.   You know better, and most here do too.

[Busa@11K]

It's just that there are a lot of super technical Busa experts on this board, so if there is anything "amiss" about the information it will be focused on.

Yeah and now it's got everybody gun shy and now NO info on handy mods ever get posted anymore....pisses me off too.  


All these fastest, smartest fucks on this board and all I see is the turbo, bling-bling info anymore.

You forgot to account for this statement:

Don't take it personally ... everyone can learn from the people who pick apart the technical aspects of the discussion.

[CID]

I am not misleading people try it with a PC2 that you have 35's in the 100%  and not on the dyno on the track

If you have a pc2 with 35's in it you have already maxxed out your stock fuel system at the top of your torque curve.  It won't enrichen ever.  Fast or slow.   You can't exceed 100% duty cycle on your injectors unless you have found a new trick.   You know better, and most here do too.

So does that mean if you're running 35s at 100%, the dry shot in the airbox (with the IAT moved) doesn't matter or still bad and why?

[grecco]

That was an excellent write up!!!!!! Please continue to do so in the future!!!!!    

I agree with BusaPwrd...

[MATT_WRIGHT]

I am not misleading people try it with a PC2 that you have 35's in the 100%  and not on the dyno on the track

If you have a pc2 with 35's in it you have already maxxed out your stock fuel system at the top of your torque curve.  It won't enrichen ever.  Fast or slow.   You can't exceed 100% duty cycle on your injectors unless you have found a new trick.   You know better, and most here do too.

So does that mean if you're running 35s at 100%, the dry shot in the airbox (with the IAT moved) doesn't matter or still bad and why?

As a general rule the Busa fuel system will support anywhere from 225 to 235 hp and still mantain safe air fuel.  The word safe is used loosely here.  This is with extreamly high dwel times on your injectors.  You run a risk locking up an injector if you hold it open to long. I am sure the top speed guys can be of more help there.  

I will over simplafy a little.
 
Your injectors pulse on and off the minimum fuel they can flow is with them closed, 0% duty cycle.  (not pulsing)  

The maximum they can flow is 100% duty cycle. (always open)

The stock map controls the pulse width, at a constant frequincy, or dwell time from 10% to around 70% stock depending on throttle position, and air speed.  

Imagine your kid anoying the hell out of you flipping the light switch on and off.  The speed of on and off never changes, just the amount of time it is left on each time.  

Something like this:


If you use devices like a power commander to extend the dwell or on time on of the injectors you will reach 100% duty cycle quickly.

There are a few solutions.  More fuel pressure which entails an aftermarket fuel system.  This is the easiest and most tunable way in my opinion to support more hp/torque.  I've made up to 310hp on stock injectors and still kept the A/F very safe this way.  

Another good solution is larger injectors.  A little harder to tune low end for really big Hp, but works great.

[SFlaBusa]

Awesome description, as a new member, posts like this are greatly appreciated!

[Busa@11K]

Your injectors pulse on and off the minimum fuel they can flow is with them closed, 0% duty cycle.  (not pulsing)  

The maximum they can flow is 100% duty cycle. (always open)

If you talk to guys at someplace that deal and test fuel injectors all day long (like RC Engineering), they will also tell you that most fuel injectors don't really flow much differently between 90% duty-cycle and 100% duty-cycle.  Their bench testing of actual flow-rate vs. duty-cycle shows the flow levels out around 90~92% duty-cycle.

People in the injector industry say to always size injectors to run at 85% duty-cycle or less at full engine power output.

[Johnnnycheese]

I am not misleading people try it with a PC2 that you have 35's in the 100%  and not on the dyno on the track

If you have a pc2 with 35's in it you have already maxxed out your stock fuel system at the top of your torque curve.  It won't enrichen ever.  Fast or slow.   You can't exceed 100% duty cycle on your injectors unless you have found a new trick.   You know better, and most here do too.

35's does not mean you maxxed the dyty cycle it means you maxed the AIT sensor to as cold as it will go. Come on Matt you can't be that slow today

[MATT_WRIGHT]

People in the injector industry say to always size injectors to run at 85% duty-cycle or less at full engine power output.

Good point!!!


I always try to set the fuel pressure so the highest # in a power commander is 0.  This way the AIT will then still be useful

[MATT_WRIGHT]

35's does not mean you maxxed the dyty cycle it means you maxed the AIT sensor to as cold as it will go. Come on Matt you can't be that slow today

One will cause the other.

[Johnnnycheese]

35's does not mean you maxxed the dyty cycle it means you maxed the AIT sensor to as cold as it will go. Come on Matt you can't be that slow today

One will cause the other.

?
Again just because you max the sensor you have no even got close to maxing the injector there are other ways of adding fuel with a pc2 still hooked up

[THEMOTORHEAD]

310 HP WITH STOCK INJ
YA BUT WHAT A/F LIKE 14-1
THATS WHAT I GET WITH 100# OF FUEL PRESSURE UP TOP WITH STOCK COMP ETC.
NOT TOO SAFE FOR SPRAY

[IronBrad]

Man I like your style: Facts and data. his thread is very interesting

I am not misleading people try it with a PC2 that you have 35's in the 100%  and not on the dyno on the track

If you have a pc2 with 35's in it you have already maxxed out your stock fuel system at the top of your torque curve.  It won't enrichen ever.  Fast or slow.   You can't exceed 100% duty cycle on your injectors unless you have found a new trick.   You know better, and most here do too.

So does that mean if you're running 35s at 100%, the dry shot in the airbox (with the IAT moved) doesn't matter or still bad and why?

As a general rule the Busa fuel system will support anywhere from 225 to 235 hp and still mantain safe air fuel.  The word safe is used loosely here.  This is with extreamly high dwel times on your injectors.  You run a risk locking up an injector if you hold it open to long. I am sure the top speed guys can be of more help there.  

I will over simplafy a little.
 
Your injectors pulse on and off the minimum fuel they can flow is with them closed, 0% duty cycle.  (not pulsing)  

The maximum they can flow is 100% duty cycle. (always open)

The stock map controls the pulse width, at a constant frequincy, or dwell time from 10% to around 70% stock depending on throttle position, and air speed.  

Imagine your kid anoying the hell out of you flipping the light switch on and off.  The speed of on and off never changes, just the amount of time it is left on each time.  

Something like this:


If you use devices like a power commander to extend the dwell or on time on of the injectors you will reach 100% duty cycle quickly.

There are a few solutions.  More fuel pressure which entails an aftermarket fuel system.  This is the easiest and most tunable way in my opinion to support more hp/torque.  I've made up to 310hp on stock injectors and still kept the A/F very safe this way.  

Another good solution is larger injectors.  A little harder to tune low end for really big Hp, but works great.

[MATT_WRIGHT]

310 HP WITH STOCK INJ
YA BUT WHAT A/F LIKE 14-1
THATS WHAT I GET WITH 100# OF FUEL PRESSURE UP TOP WITH STOCK COMP ETC.
NOT TOO SAFE FOR SPRAY

I always have injectors cleaned and several sets calibrated to match them up for big spray applications.  I am told some of the turbo's run 100#'s on high boost.  The most I have ever plugged an injector with is 85psi on spray.  Off spray I usually use 47.5 psi.  I am afraid of locking up an injector.  I am going to have to plead ignorance as to why you are running so lean at 100#  I will not let a nitrous bike go leaner than 12.8.  Does it have anything to do with intake temperature charge?  I am hitting the back of the intake valves with liquid nitrous.



At 85psi stockers flow 373cc

[eddie j]

I did the mod today-hope it helps but can't hurt. Of course I'll find out if it helps when summer gets here.

[THEMOTORHEAD]

LOCKING THE INJECTORS
LOL
NEVER HAD IT HAPPEN YET
THOUGH I BUSTED SOME CAR ONES IN THE 130# RANGE
NA ITS MORE OF A BSFC ISSUE
AND YER USING FUEL MORE EFFICIENTLY WITH SPRAY THATS WHY

[dcnblues]

Lots of guys have moved their IAT's but thats a nice instructional thread you put togethor. The other option, that I did, is to leave the sensor where its at and wrap the exposed part with some foam insulation..

  heat shield, with the reflective material facing out.  And who gets stuck in traffic on a motorcycle?  Are there people who ride busas who actually wait behind cars?  Not trying to diss anyone, just trying to imagine scenarios where you can't get twenty mph worth of air flowing through the radiator for more than a minute or two, but still need to run the engine.

[Busa@11K]

Not trying to diss anyone, just trying to imagine scenarios where you can't get twenty mph worth of air flowing through the radiator for more than a minute or two, but still need to run the engine.

Any place you have tons of frickin' traffic   and it's not legal to split lanes!

I got stuck in a 5 mile long traffic jam on I-90 once due to a fatality accident.  Busa started overheating, so started riding 20 mph down the shoulder.  A lot of asshole cagers were pissed and would try to swerve out or honk and flip me off as I went by.  Always pricks around ...    Even if my bike didn't overheat, I would have rode down the shoulder ... not going to sit in a 2 hour traffic jam like that if I don't have to!