Running with no air box, pods or filter

[hitman87]

I have seen two monsters running no air box or pods just straight throttle bodies. I like the open area there. What Ill effects will come from this? Will I need to retune get a pc3 or will the bike just run like crap. Boomtubes with this set up would be hot!

[ducatiz]

you need something at least trumpets and a grating to knock away debris.

basically, everything is gonna get sucked into the engine and it's going to wear away the rings/cylinders much faster.  dirty your oil faster, and by dirty think in terms of sand.

i wouldn't do it except on a race bike that i am rebuilding often, and even with those, i'd use the trumpets or pod filters.

[MotoCreations]

I've run open velocity stacks for years without problems and tens of thousands of miles.  Advantages: great sound, easy to tune.  Disadvantages: potential for sucking dust/rocks, water, spitting fuel (FCR's), and a few others ala potentially less horsepower due to non-airbox. 

On others I've run mesh screens or pre-filter socks (what you put over a filter to act as a pre-screen).  The latter option is the most I'd do anymore for a filtered bike.

If you do the above -- your air/fuel ratio will go lean.  You need to correct that either carb'd (rejet) or FI (PCIII).  If you put a set of my BoomTubes on it the air/fuel ratio will go even leaner.  Thus correct the air/fuel ratio the right way and dyno test / confirm before you do damage to your engine.  Make sure you know how to tune/jet/PCIII your bike or get a knowledge mechanic to do it. 

It's like the open belt covers question -- some do it without problem, some did and paid the price (and now run belt covers), some did and paid the price (and still run without belt covers!) -- and others won't try it at all because of the potential for an expensive repair possibly.  Nobody is right and nobody is wrong.  It's a personal preferance.

[Norm]

A lot of race bikes run without any filters, if you do, prepare to go thru some cylinders and rings (FHE).

[cokey]

I've run open velocity stacks for years without problems and tens of thousands of miles.  Advantages: great sound, easy to tune.  Disadvantages: potential for sucking dust/rocks, water, spitting fuel (FCR's), and a few others ala potentially less horsepower due to non-airbox. 

On others I've run mesh screens or pre-filter socks (what you put over a filter to act as a pre-screen).  The latter option is the most I'd do anymore for a filtered bike.

If you do the above -- your air/fuel ratio will go lean.  You need to correct that either carb'd (rejet) or FI (PCIII).  If you put a set of my BoomTubes on it the air/fuel ratio will go even leaner.  Thus correct the air/fuel ratio the right way and dyno test / confirm before you do damage to your engine.  Make sure you know how to tune/jet/PCIII your bike or get a knowledge mechanic to do it. 

It's like the open belt covers question -- some do it without problem, some did and paid the price (and now run belt covers), some did and paid the price (and still run without belt covers!) -- and others won't try it at all because of the potential for an expensive repair possibly.  Nobody is right and nobody is wrong.  It's a personal preferance.

i keep reading a lot that monsters come from factory pretty lean.. what's the AFR of say a stock 09 696?   too lean is bad, just the right AFR will give you more HP i'm so use to factory (cars) being too rich..

[El Matador]

i keep reading a lot that monsters come from factory pretty lean.. what's the AFR of say a stock 09 696?   too lean is bad, just the right AFR will give you more HP i'm so use to factory (cars) being too rich..

The bikes come like that to be able to pass the stringent EU smog laws.

[hitman87]

i doubt i will run without the pods. i want to lighten/open the bike up so the plan is pods with no tb's crankcase breater mod and boom tubes. maybe a slight loss in power, i'm not to concern with that i want the open, more is less look and to loose some pork from the bike

[cokey]

The bikes come like that to be able to pass the stringent EU smog laws.

true, i've read that...  do you know what the stock AFR is though or wat a good AFR for these bikes might be.. i know it depends on heat, like in a turbo application 11.5 afr is optimal due to the heat of a turbo.. in N/A applications i've seen people use up to 13 afr (maybe more) depending on the type of gass; etc...  i'm guessing not many people install AFR gauges on their ducs?

[caperix]

true, i've read that...  do you know what the stock AFR is though or wat a good AFR for these bikes might be.. i know it depends on heat, like in a turbo application 11.5 afr is optimal due to the heat of a turbo.. in N/A applications i've seen people use up to 13 afr (maybe more) depending on the type of gass; etc...  i'm guessing not many people install AFR gauges on their ducs?

Not much room to install a AFR guage but widebands are an important part of dyno tuning.  12-1 to 12.5-1 is generaly thought of the best mixture for power, more fuel is sometimes used to help cool the cylinders, may be an advantage on air cooled 2v motors.  Cats work best at a 14.7-1 mixure so most vehicles with a cat tend to run in that range.

[redial]

Cats work best at a 14.7-1 mixure so most vehicles with a cat tend to run in that range.

mm, 14.7 is simply stoich for gasoline combustion, meaning at that ratio all fuel will be burnt. most machines run a tad rich because its safer than lean.

as was mentioned FI applications usually (always) run much richer because unburnt fuel cools air, and air that is compressed becomes hot. it doesnt necessarily have anything to do with being air or liquid cooled.

to say that "this ratio is best" or xx.xx yields the most HP is a little rediculous. you need a dyno and a wideband afr  meter or you are just guessing

[cokey]

True true.. well as a cager I knw all of this.. especially with turbos.. just seeing if anything is diff from a bike as I'm not use to N/A applications only forced induction..  thanks for all the input guys..