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No Snorkel in a Rainstorm?


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A lot of people on this forum seem to run their FZ with the snorkel removed. So my question is, have you ever been caught not only in a rainstorm, but had to ride for an extended period of time in the rain, and of course, did it do anything to your bike? Next question would be did you ever check to see if you got any water in the airbox?
 
I only found one comment about somebody who used a hose to test it, but that's not like several hours of rain riding. I plan to put a pipe on in the spring, and while I realize that removing the snorkel will make things perkier especially with a reflash or controller, I'm not sure if I want to deal with engine problems on a trip from water in the airbox.
 
I am one of those folks that wouldn't hesitate taking my FZ on a ride of literally any length. Years ago I did a 2300 mile 11 day trip through New England on a Yamaha 750 Maxim (Awesome Trip!) where it rained 8 of the 11 days. I plan to do several long rides this summer on my FZ. I had one 250 mile/day trip already and that darn bike was just fine, so I know I can go as long as reasonably possible on it.
 
So any wet weather riding experience with the snorkel removed would be greatly appreciated!
 

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Yes
i have been caught in several thunderstorms on the way into/home from work
Never had an issue with the rain getting in
 
even if a tiny bit of water hits the filter its more than lileley not going tk go through easily
theres also the fact your throttle bodies have separate intake tubes feeding them inside the air filter/intake box
this adds a slight restriction and may help to separate the moisture out

ATGATT... ATTATT, two acronyms I live by.
 

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I still don't understand the motivation to remove the snorkel despite reading the threads about it on this forum. It seems to be one of those things that's done by a lot of track dayers/racers and the street riding community just picked it up for dem horsepwr gainz brah
 
My thoughts from an engineering perspective:
-The snorkel has an identical cross section area as the airbox intake. So removing it doesn't change the amount of air allowed to go in, given the same velocity of air
-Now this brings up velocity differences when the snorkel is in vs. out, if it exists. With the snorkel in the stock position facing backwards, the engine has to do work to pull fresh air in, and has to even when the snorkel is out. If the snorkel were facing forward, then you'd have a forced ram intake effect, but allowing more a lot of debris into the airbox.
-The opening of the snorkel faces the rear of the bike, so that if water enters the air ducts, it will move downwards through the fairings before having a chance to enter the airbox. Removing the snorkel makes the levels of where water will flow out and the airbox intake the same. Thus more water in airbox.
 
From a street riders perspective:
-Let's be honest, we're street/commute/joy riding most of the time. If we're looking to brag about the potential horsepower gains from removing a rubber boot, we're on the wrong bike in the first place.
-If riding in the rain, I wouldn't want to worry about air getting in my intake, the same way that I don't worry about it in my car.
-The manufacturer has more experience in designing a bike than I do, and they do a great job of making them last.
 
From a dedicated track day/racer perspective
-You're definitely on the wrong bike lol; pick up an R6
-If you're dead set on the FZ for a track bike, then experiment, gather real data, compare, then make a judgement like any other dedicated racer would.
 
Sorry for the rant, but this is the engineering side of me coming out. If something doesn't make sense I explain why I believe so, until one side of the issue is proved wrong.
 
Edit: http://fz07.org/post/6121/thread Dobeck performance has even noted the effect of removing the snorkel. Of course it all depends on what type of performance you want to achieve. 

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Opening size isn't the only factor in influencing air flow volume. Even a well-formed bend has flow losses. How much? Perhaps only a small amount, but more air comes in with it off.
 
I've run with mine off for about 14k, and the filter shows no excess soiling or moisture. I checked/replaced/cleaned the filter at 8k and at 16k on my way to the spark plugs. You are correct, though, removing the snorkel certainly increases debris reaching the filter...perhaps slightly more than the airflow gains...
 
Why did I do it? The EJK fuel set up for the full Yoshi I got called for baffle in, snorkel out. I'm guessing the bike Dyno'ed a bit better off than on when they mapped it.

O judgment! Thou art fled to brutish beasts,
And men have lost their reason. Bear with me.
My heart is in the coffin there with Caesar,
And I must pause...till it come back to me.

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opening size only influences the flow volume if it is a straight shot
our bike more or less has 2 intake channels
The snorkel does infact restrict the airflow into the air filter because it sots roughly 8mm above the bottom of the filter when installed
air passes through the filter into an antechambre of sorts to resonate and lose momentum? Before being pushed into the throttle body runners

ATGATT... ATTATT, two acronyms I live by.
 

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On UK bikes the snorkel points forward and there is a big vacuum controlled flap at the
rear that bypasses the snorkel it is usually open only closing when needed to pass the
noise regs, you can see the vac controller in this pic.
 
DSCF5562_zpsed7bde96.jpg
 
Water has long been used as a power booster on all sorts of hi powered piston and jet engines
and only becomes a problem when you get great big globs of it all at once, mine as the flap bypassing
the snorkel and as been ridden in rain of biblical proportions for hours on end without the slightest problem.

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I just talked to (forget his name, sry) a representative at Dobeck a few days ago and that question came up while talking about the differences between snorkeled and unsnorkeled. I told him that I and some others here had talked about this before and he pointed out that IF water did somehow manage to get inside it would have to go through the filter (be sure the filter is held down) before it reached the engine so therefore it was highly unlikely that a rain storm would cause any problems.  Still leery, not racing anyone, just leave it on for peace of mind. My 2/100.

Beemer

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I just talked to (forget his name, sry) a representative at Dobeck a few days ago and that question came up while talking about the differences between snorkeled and unsnorkeled. I told him that I and some others here had talked about this before and he pointed out that IF water did somehow manage to get inside it would have to go through the filter (be sure the filter is held down) before it reached the engine so therefore it was highly unlikely that a rain storm would cause any problems.  Still leery, not racing anyone, just leave it on for peace of mind. My 2/100.
 
I haven't looked into this bikes airbox but the airbox of my old bike had a drain with a one way check valve for moisture and the throttle body intakes are raised from the bottom of the box. Might be a similar setup.
I had my snorkel out for a little bit but put it back in. Didn't really notice a difference. If I was to remove it permanently I would just cut off the inside sleeve and leave the snorkel elbow on there.
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I've also been in many a monsoon-like rainstorms and haven't had any problems. Water drainage doesn't appear to travel into the filter area.
 
Also, when I was at 2wheeldynamics they did a bunch of dyno runs, like 5 different ones with different variables. One run was just taking the snorkel off and it did produce gains. I don't remember how much. Building HP isn't best looked at when assessing if doing one thing produces 15HP. It's often a cumulative of a few things.
 
All I know is, the dyno chart as a whole shows significant improvement with the cumulative changes and I gain about 7 MPH top speed on the country road I ride (not exaggerating, probably understating by a MPH or two).

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 I would just cut off the inside sleeve and leave the snorkel elbow on there.
That's what I did. I just cut it right below the "groove". More flow without the sleeve and no worries about water getting in there.
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Dynoed mine with snorkel in and out and no significant difference. The Dobek dyno graph with one of the pipes shows the same. I run mine with a home made ( and rough until I get a chance to make a new one) curved inlet "low Stack" . The hole has been opened to level with the filter edge. I have ridden in monsoon ( actual not monsoon like) rain and have had no issues at all. It's currently made of a soft petrol resistant foam but eventually will be a carbon one. Also blanked the area in front to reduce the hot air from the radiator .
 
DSCN0974.jpg
 

Go forth and modify my son...go forth and modify...

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Dynoed mine with snorkel in and out and no significant difference. The Dobek dyno graph with one of the pipes shows the same. I run mine with a home made ( and rough until I get a chance to make a new one) curved inlet "low Stack" . The hole has been opened to level with the filter edge. I have ridden in monsoon ( actual not monsoon like) rain and have had no issues at all. It's currently made of a soft petrol resistant foam but eventually will be a carbon one. Also blanked the area in front to reduce the hot air from the radiator . 
DSCN0974.jpg

.....
Why must you show off your pretty toys
Why the blanking foam?
I couldve sworn there was a piece of plastic there already to serve that purpose

ATGATT... ATTATT, two acronyms I live by.
 

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There is nothing there on my bike to stop the hot air going straight from the radiator to the air inlet. This helps the cool air from the front air inlets ( which I have opened substantially) flow towards the inlet. There is some up were the ABS and rectifier live to help. Not pressure closed just simple blanking and directing. From my proddy racing days. This was during installation and hasn't been taped yet.
I don't think my stuff is pretty unless you are a devotee of Bauhaus. I tend towards function rather than form form it's own sake.

Go forth and modify my son...go forth and modify...

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any pics of the more open inlets?

ATGATT... ATTATT, two acronyms I live by.
 

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There is nothing there on my bike to stop the hot air going straight from the radiator to the air inlet. This helps the cool air from the front air inlets ( which I have opened substantially) flow towards the inlet. There is some up were the ABS and rectifier live to help. Not pressure closed just simple blanking and directing. From my proddy racing days. This was during installation and hasn't been taped yet. I don't think my stuff is pretty unless you are a devotee of Bauhaus. I tend towards function rather than form form it's own sake.
Makes good sense to me since cool air will help to make more h.p. than hot air but what I do have to question is do you have any way of knowing what percentage of hot air is being blocked? A little ... a lot? How does a person get the answer to that, by using some type of thermal sensor inside the air box itself? It would be nice to see a pie chart/graph that shows the differences. You have the gadgets it seems, can you do a test like that, with a temp sensor? I'm very curious about this and you seem to be the type of guy that would like a challenge like that. A chart would be awesome. Thanks!

Beemer

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Dynoed mine with snorkel in and out and no significant difference. The Dobek dyno graph with one of the pipes shows the same. I run mine with a home made ( and rough until I get a chance to make a new one) curved inlet "low Stack" . The hole has been opened to level with the filter edge. I have ridden in monsoon ( actual not monsoon like) rain and have had no issues at all. It's currently made of a soft petrol resistant foam but eventually will be a carbon one. Also blanked the area in front to reduce the hot air from the radiator . 
 

So, did you change your fueling when you removed the snorkel, or did you just pull the snorkel and dyno it with the same fueling map/settings?

O judgment! Thou art fled to brutish beasts,
And men have lost their reason. Bear with me.
My heart is in the coffin there with Caesar,
And I must pause...till it come back to me.

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Too much work, Beemer. I doubt I could measure it anyway as it is really only effective when the bike is moving. Like trying to tune bikes with pressure loaded inlets on a dyno problem.
I live in the tropics so I have always tried to direct the hot engine air away from the air box, tank and the seat. It's not only hot air that will reduce HP but hot fuel.
The hot air is also uncomfortable on the rider. I could have had a Ducati tourer a few years ago for very cheap but one run on it in summer and you knew you couldn't ride here for most of the year. A blessing in Europe but hell here. Sae reason I avoid underseat exhausts.
One thing about the fake tank is it protects the real tank from the sun. Tanks in the town I have moved from would get so hot left in the sun you couldn't put your legs against them. Hot radiator air is no help.
As a byproduct ( colatteral antidamage?) the air is drawn better FROM the area with the rectifier and ECU to help keep them cool. In Townsville rectifiers often have a short life when tucked away from airflow. Kawakas and BMW's particularly would stick them with no airflow and they would just die. Over the years I just got into the habit of moving them or ensure air went past them on every bike. That is as important to me here as air box airflow.

Go forth and modify my son...go forth and modify...

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panterlero,
The afr's are measured at the same time and there was not significant difference. Remember my bike was reflashed and the O2 sensor still works as well just to adjusted tables so the system would adapt. The manual says there is an "air pressure sensor" somewhere but I haven't found it yet. I assume that would adjust the ecu also, if it isn't just to work the flap thing we don't have on the Aussie bikes.
If you were running a PCV I suspect you might have to readjust...maybe. Just doesn't seem to be enough difference with and without. It is possible the smaller inlet and the bend resistance is similiar overall to the flow that the flat plate turbulance of a plain hole. Don't know.

Go forth and modify my son...go forth and modify...

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The manual says there is an "air pressure sensor" somewhere but I haven't found it yet.
It is plumbed into the left side throttle body via a hose, and is located directly above and slightly forward of the TB.
 

J.D. Hord
 

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Do you know if it acts like a car one to adjst the ECU or is it just for the flap valve in the air box?
 

Go forth and modify my son...go forth and modify...

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No flap here, it's part of the injection system and sends data to the ECU so it can decide on fuel and spark.  I'm not sure if it has its own table like some bikes, or simply offsets tables.  2WheelDyno might be able to answer that.
 

J.D. Hord
 

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Thanks for that. I was wondering. When I found the air temp sensor was not in the inlet airstream I was wondering what the control architecture was. Starting to make more sense now.

Go forth and modify my son...go forth and modify...

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Thanks for that. I was wondering. When I found the air temp sensor was not in the inlet airstream I was wondering what the control architecture was. Starting to make more sense now.
I moved mine to the inside of the 'carbon' scoops
what did you do to your inlets exactly to open em up?

ATGATT... ATTATT, two acronyms I live by.
 

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Just cut and shaped the plastic around the inside to allow it to flow through better. The rectifier, ECU and Air temp are all now in behind the left and right mesh.
 

Go forth and modify my son...go forth and modify...

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I got the k&n filter for mine today. I dont ride in the rain since i have no gear yet, but if i was to either remove it or face it forward as a " ram air" it wont change the fuel to lean much?? Im completly stock and dont intend to do anything at the moment.

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