HELP WANTED - I screwed things up !!!

[FLATSIX]

Today I took off my tank, inspected the K&N airfilter + prefilter - cleaned it (did not oil) and reinstalled.

I also saw a sort of mousse falling out of the upper plastic top of the airbox - in the rectangular smal groove in the airbox, where air goes in - on top you find a piece of mousse glued- I took the parts away and cleaned everything as it fell apart from age ('1997 !)

Mounted the gastank and took a ride :  bike stops pulling at 3500 rpm +/- , it is like she does not get fuel. Low rpm  and idle O.K. - but she holds in.

Came home and with a light inspected the fuelline and the vacuum line to the petcock and on the #6 carb- but then I thought to see a line between the tANK and the frame - I pulled to get it free and suddenly there came a whole vacuumline with a rubber T- mounted + the last end +/- 1 foot. 

WHAT IS THIS - WHERE DOES IT COME FROM.

IS THIS THE CAUSE OF THE PROBLEM why she restrains herself ? What does that pipe do?

COULD THE REMOVING OF THAT PIECE OF A SORT OF FOAM (thickness 10mm) be the cause of the problem with acceleration ?

I really need help because I screwed it up !

[Hoser]

That is your tank vent and needs to be pluged back into the bottom of the tank.  Surprised it ran at all. Just let the loose end back down to the bottom of the bike. Don't worry about the open nipple, it's supposed to be that way.  Hoser

[FLATSIX]

I must first empty the tank because now she is 100% full - but from what I can see with a lamp there is the tank vent hose still attached to the underside of the tank + at the bottom there are the 3 hoses like it should.

The T-piece leg that is free must have been in something because you can see it.

I have an European version, perhaps they are different. Cannot the T-piece and the free end come from carburator or something else?

Hope I don't have to take away all my chrome or even the airbox?????

The piece of foam that I took away on top of the air cleaner housing cover, could this cause the failure of power ?

[Black Dog]

That piece of foam may have been the K&N 'Pre-Filter'...  Many that have the K&N don't use it, so it's not necessary, but if it was falling apart, I'd check that none of it got in the air box.

Black Dog

[Scott from FL, now in Maine]

I still think what you have is the tank vent line and needs to be installed as mentioned above. The T in the line is normal and is supposed to be an open end attached to nothing. You should have 2 hoses hanging out of the bottom of the bike, one is the tank vent, the other is a vent from the engine. I am betting your mistaking the one from the engine as the tank vent. I also agree with the foam piece that fell apart being the K&N prefilter. Some use it some don't. With out it the worst that could happen is you may find it runs a little lean because of less airflow restriction. Whether you notice that or not would depend a lot on how it was running before
(i.e. a bit rich is now normal, normal might be a bit lean) But the removal of that filter shouldn't effect it to much on normal performance.

[BF]

Is this what you're talking about?......

http://www.valkyrieriders.com/shoptalk/AirBox%20VentHose/venthose.htm

[FLATSIX]

Yes, the hose that i pulled loose is definately the tank vent hose that I pulled from near the sidestand above. At the other underside I have 3 hoses : 1 carburator drain tube
                                     1 reserve tank coolant overflow tube
                                      1 breather storage tank drain tube that has a plug in it

So keeps the question of the Tpiece, as I see it it has just been removed from something because the hoseniple is not dirty and realy looks fresh as if it was attached to something, are you sure that it is only there for nothing : it is located 1 foot higher then the bottom end of the tank vent hose at the sidestand.???

The piece of foam that was falling apart from oldness and that I therefore have removed is not the prefilter : these was nicely on top of the K&N filter - has nothing to do with it (lucky it was there to retain the small pieces that came loose ) No, this small piece of foam (similar material as the prefilter) is glued by Honda into the air-inlet of the airbox housing cover - the air can come in through the inlet, but Honda made the airinlet less high by adding a piece of foam (like the pre-filter) to restrict the air. Now I removed it and the opening gets about 1/2" wider as the foam isn't there anymore.

I read something about removing that similar piece written by an Austraiian Valkdriver, he had also problems, and had also a bike similar to mine : EXPORT-version. Mine is a STANDARD "97 but EUROPEAN version - we don't have pair valves , don' have to desmog , have other jets etc. etc.

Anyone familiar with the European Lady concerning :

1) the T-piece : may I leave it as is or does it have to fit in something?
 
2) the small glued foam (mini-prefilter) in top of the airbox cover - can it cause problems when removed ??

Thanks for your help because I need it !!

[FLATSIX]

Hello Key Boarder, no, it isn't - it is the fueltankhose + T-piece in it + 1 foor of hose that goes under the bike mounted at the sidestand.

Need to know for sure if T-pice must be mounted somewhere, because it looks as it came out of something.

I don't have airvent hoses on my bike because european version : only 1 vacuumhose - #6 carb to the petcock for fueldelivery, all other 5 carbs are just plugged, no pair valves , no vacuumlines.

 

[Daniel Meyer]

The T in the tank vent line definitely does NOT plug into anything. It is a vacuum break...as you use fuel the tank draws air in the vent hose, the T keeps it from drawing water up from the bottom if you are running in the rain...and if you overfill, the tank will overflow a bit from that hose...the T allows the liquid to run straight through to the bottom of the bike, but breaks any possible siphon by letting some air in behind the liquid.

[FLATSIX]

Daniel, thanks for your explaination - I am convinced and will reinstall the tankfuelhose back to the bottom and leavind the T for what it is.

Do you think that when the tankvent hose is blocked or partially blocked (I think it was stuck between the tank and the chassis) - that this can cause the loss of power from 3000 - 3500 rpm?  I hope this is it, because then I don't have to worry about my piece of foam in the airbox cover.

For me it is difficult because your bikes in America are slightly different to our european version.  It seems that you don't have this foam in your airbox?

[Ghillie]

Generally speaking, an improperly vented tank will slow the flow of fuel to the carbs/injectors resulting in a loss of power. Someone correct me if my understanding of this is incorrect.

[FLATSIX]

I am curious - will deblock the vet hose and take a testride, I hope she will pull again like before.

If not then it must be that small piece of foam that I took away - we will see.

THANKS to you all - I keep you informed !!!

[Daniel Meyer]

Oh yeah, a clogged or kinked vent hose can cause loss of power...it can also stop you dead...or be okay...depending on temperatures (and whether they are going up or down), how much fuel is in the tank, etc.

Step one if you are losing power...check the tank vent. Step two, the petcock. After that and more rare (on a honda) it's air filter or electrical.

If you suspect venting is a problem...and you're stuck on the road or not able to take the tank of and check...well, look closely at the pic...

[Grandpot]

Daniel:

Nice McGiver trick

[FLATSIX]

Hallo, I am back again..............

Did check the tank vent hose and reinstalled the back part - took her for a ride : 

THE SAME - I CANNOT GET HER PAST 4000 RPM - AT 3500/4000 RPM SHE HOLDS IN EN STOPS PULLING !!!

So I ordered at the HONDA dealer that small piece of foam (mini-prefilter) that sits mounted in the airtake of my airbox-cover.
Tomorrow I will have that - but will only be able to mount this saturday-evening or sunday-evening.

I'll hope this will cure the LADY .....................

KEEP YOU INFORMED.

[Master Blaster]

First off if the vent hose is connected to the tank and is kinked, it will cause a stall.  If the vent hose is disconnected it will have no effect except if you overfill the tank, fuel may vent on top of your engine.  The K&N comes with a prefilter thats not necessary, and will not have a detrimental effect if not installed.  If you clean the K&N and over oil it  it can act like a choke and restrict the air flow.   There is a cleaning kit made for the K&N that contains a solvent and oil.  If you used that, and followed the directions you should be ok.  If it ran ok before you jacked with the filter, your problem is more than likely in that area.   Could you have used some cleaning method that may have resulted in the filter being partially blocked?  I would try Daniels method to break the seal in the fuel cap and see it that cures the stall.  If it does, then you have a vent problem.  If it stays the same, you probably have a filter problem, and its not caused by the prefilter being removed. 

[FLATSIX]

Today I made a testride - result : the same - max 3500 till 4000 rpm and that was it!

Did also the Mc Guyver trick with the tank - same result.

So I ordered now a complete new airbox-cover with the new foam in it as they don't sell that little piece of prefilter separately.

Honda-dealer says also that without this piece the motor gets too much air - the Honda CBR has it also.

Monday I will see if all O.K. again.

(has nothing to do with the K&N prefilter - it's the small prefilter mounted in the original airbox of an European FLATSIX !!)

[Daniel Meyer]

Just for grins...take a look at the #1 coil...horizontal just underneath the upper left frame rail...it's easy to knock the power/ground wires loose on that one while putting on/off the tank...

[sandy]

He has a fuel delivery problem. Is the vacuum line to the petcock good? Pinched or a hole/split in it? Cover set has failed? I feel that at higher rpm's, he's losing vacuum which is shutting off (or partially closing) the petcock.

[FLATSIX]

Sandy, I am practically convinced that it is all due to the fact that I took away that small piece of prefilter - now I recieve too much air as the air-restrictor is gone - remember- we have smaller main screws as in the States.

When the new piece arrives then I'll see : fixed or not.

It reacts as if it is starving for fuel - perhaps it is the opposite: gettin too much air - which comes at the same....

[Chrisj CMA]

F6.......you arent going to hurt anything by running without that foam thing.  To remove the tank you have to disconnect at least 3 lines: fuel to the petcock, vacume to the petcock and the tank vent hose. 

The symptoms you describe can either be caused by the vacume line leaking that goes to the petcock or the tank vent being kinked under the tank.

To be sure theres nothing going on with the line to the petcock, Id replace that with 5/16 ID fuel or heavy duty vac line and either make dang sure the vent is not kinked or just unplug it altogether and go for a ride.  that little tube tends to get buggered up at the joint where ti connects to the tank and almost kinks itself.  I had to cut off a half inch or so of the vent once to get a good hose again, then later I just replaced it

[MP]

I know the US valks do not care about the foam.  The export bikes do use a smaller main jet, and it seems to me that a member from Australia also had the same problems.  He HAD to use that foam, or it would not run right, until he changed the mains to US size.
MP

[FLATSIX]

MP - you are right , on 17 march 2009 WOODY from Australia did a post about "acceleration problems with my baby".

Here a piece of his text :  "Hi All;


Im baaaakkkkk, Firstly, thanks to all, The fixes and support were and was great.
The problem appears to be the Restrictor in the intake in the airbox. I had a look into the airbox intake and found the remnants of a sponge restrictor sitting on top of the vanes in the intake. I inserted a piece of sponge into this area and took the bike for a ride, it went like a bat out of hell until suddenly it choked and ran like a sick snail. I thought I stuffed it and limped home, but when I took off the tank the sponge was gone. It was sitting on top of the air filter, obviously sucked into the airbox and sitting on top of the air filter choked off the air.
I found a better way of inserting the sponge and took it for another ride, problem fixed.
There is still a little hesitation at full throttle, but its so much better and the little hesitation is minimal.
NOW, a question. If there is a restrictor in the Aussie airboxes, is this the same for USA?
If not, what size jets do you have in the carbs? (We have .78)
Also, do you have the same noise restrictions (exaust noise) as we have in Aussie land, perhaps choking the exaust could be contributory to the issue. Our BIG BROTHER is so ingrained over here that we are regulated in everything and any changes have to be "Approved" or we get fined and treated like criminals.
I was thinking that I could have the potential to increase performance by re-jetting and removing the airbox restrictor. Has anyone any suggestions.
Thanks to all again, especially Bostonrats, johnny kiwi, but not to forget the rest I'm grateful to you all. The best thing is that I now have a bike running like new, and I know all the bits and pieces are correct, the vacuume hoses really needed replacement, I would never have considered this as a need until you advised me and this was a must


I canot get the original piece of foam at HONDA - they don't have it anymore - so I sent a personal e-mail to WOODY asking what he has put in to cure Baby- we will see his reply and when fixed I give you the results.

Many thanks - I hope I'll be able to make the Lady healthy again ......then I will be too.............

[Madmike]

forget about the foam, make sure the air filter is not obstructed and then reread the suggestions given to you by Sandy and Chris.

If you are convinced that you really, really, really need a piece of foam you could fashion something out of a piece of foam salvaged from a mattress or something similar and glue it in place with some weatherstrip adhesive after ensuring that the housing is clean, degreased and dry where you want to put it in.  If the foam acts as a restrictor then density should not be much of an issue as long as you reduce the area of the cross section of the air inlet by a similar amount as the original did.  

Is this actually a reducer for air flow or is it to reduce engine noise that is transmitted back through the air inlet??

[FLATSIX]

Here's the reply of Woody from Australia :

"Hi Flatsix;
The foam is about 12cm thick and the full width of the opening. It is about the fill length of the recess at the top.
I tried to glue in some petrol resistant foam (sponge) such as that used in air filters, but the glue gave and the foam ended up on the top of the filter and blocked the air filter. The result was a sudden and catastrophic loss of power.
I then had a look around and found one of those sponge paint applicators that was wide enough to fit in the opening. About 12 cm thick. I had to cut it to size and I used two self tapping screws to hold it in place.
Im not sure if it was the best idea, as I wnt for a ride yesterday and it seems to be getting the old hesitation back. I suspect the sponge is not petrol resistant and is breaking down.
A gentleman from New Zeland suggests using a stocking to restrict the flow. Ive not tried it yet but I may have a go if the above is the problem.
Long tern I believe the best method will be to re-jet the bike with the correct jets (1mm). I cant get them in Australia, but I may be able to import them.
Best of luck, let me know how you go.
Woody.


I will now try to find a 13mm (1/2") thick sort of pre-filter, cut it to shape/dimensions and glue it in + testride - you will hear the results soon !!!!!!!!!!

[FLATSIX]

Hello ALL !!!

I just went to a moto-dealer in the neighbourhood to find me a piece of gasoilresistant foam to put in top of the airbox.

I had the upper plastic airboxcover with me and showed it the man - he laughed at me and said that it will not be the cause of my powerproblem - years ago Suzuki had also air-restrictors in their airboxes, they simply took them out and the machine kept running like before.

So he had no foam for me, but I was convinced that again this small piece of foam could not have that great impact on the acceleration - and I mounted the airfilter (K&N +  prefilter) back - put those 3 lines on it and checked everything on thightness and cracking etc. like you guys advised me.

Then I went for a ride :

RESULT : THE SAME - WHEN OPENING THE THROTTLE SUDDENLY - NO POWER - 3500-4000rpm and we are done - no acceleration - machine drives like an old woman of 99 years)


So, I will take the gastank back off, airfilter open + will find today a piece of foam that I wil glue at the inside +/- like it was - if then the Lady reacts as she did before - then 100% the cause is that thiny piece of foam that blocks partially the air to prevent the mixture to get too lean when opening throttle .

Keep you informed !!

[FLATSIX]

Here you see the upperpiece of the airbox - WITHOUT THE FOAM.  I think that the US-Valks all are this way.



Here you see the white piece of foam that I have to glue in the airbox-cover to restrict the air, because when I took it away the bike does not want to pull anylonger- stops at 3500/4000 rpm.



This is the final result - the white foam is glued on top of the cover - the air is sucked in but find a restriction through the foam - the export Valkyries have much smaller jets then yours in the States. I think that to compensate Honda had to make this airreductor.



Now the thing is drying, as I don't want that the piece is sucked on top of my pre-filter.


I will let you know the final result : normally my Lady shouldn't hesitate when I open the throttle , and she must pull like before: when this is, then there is no discussion possible: that small piece of foam is definitely necessary in an European Flatsix!

Dimensios of that foam :  92 x 110 x 8 mm. - I took it from a vegetable-store , to avoid dammage of the grapes they put white foam between the bunches of grapes - I got a piece and it is now in my Lady  (went first to all local dealers of bikes - cars etc. - nobody had something...........)

Til soon with......GOOD NEWS (I hope..... )

[FLATSIX]

Hello,

I made a testride and ...YEP....she pulls again till 6500 rpm. It is definitely the air that has to be restricted on exportbikes.

I have to gibe a little bit more trottle then usual - so I think she gets still a little too much air, but no problems with the 3500/4000 rpm witholding, now she klimbs in the rpm's. When trottle opened very quick then there is a slight hesitation that I did not have before.

My Honda-dealer says that normally before 10 july they must be able to deliver the original airboxcover with the original foam in it - then my BABY will be back for the full 100%. In the meantime I can ride her and I have learned again.

SO FOR EXPORTBIKES IF PROBLEM WITH ACCELERATION AT 3500/4000 RPM SEE ON TOP OF THEIR AIRBOX TO LOCATE A FOAM, IF IT IS NOT THERE THEN PROPABLY THIS WILL BE THE CAUSE !!

Thanks to you all for your advice 

[MP]

Glad you got it fixed.
MP

[Hoser]

Way to keep after it flat six, glad you stuck to your guns!  Hoser

[Madmike]

Glad to hear that you resolved your problem by installing the foam to restrict the air flow to the intake - I most certainly didn't think it would make a difference and would like to understand why it is needed.  

I wonder if you could further improve performance by getting rid of the K&N high flow air filter??  Did you notice any changes when you first put it in??

[FLATSIX]

Hey MADMIKE,

There are indeed quite a lot of differences between the same product : the VALKYRIE and the exportversion called F6C.

These are due to the fact that each country has its own standards (emissions - decibels of exhaust- etc.) and HONDA had to meet to this "laws" before they could sell their Flatsix to Europe , Australia etc.

These are the differences that I met while reading your technical board for years now:

-my LADY has on both sides on the tank : F6C and not the emblem VALKYRIE like yours - the name Valkyrie has something to do with the second world war - this name was used for the conspiracy to kill Hitler at that time, so HONDA WOULD NOT WANT TO MAKE A SCANDAL IN GERMANY BY USING THAT NAME AND GAVE THE EXPORTBIKE ANOTHER NAME : F6C '(flatsix custom)

-my bike cannot be desmogged because there is not such installation on the exportvalks : this means no pair-valves, etc. - yours is called a "exhaust emission control system", ours is called a "cranckcase emission control system. My bike only has 1 vacuumline on the #6 carb that goes to the petcock - all other 5 are capped with rubber caps. We have also 1 cranckcase breather tube + plug going to the bottom of the bike.

-My bike has standard #78 main jets, yours I don't know, but to give the good combination of mixture : air/fuel by opening throttle suddenly HONDA had to put a small piece of foam in the airintake of the airbox to prevent too much air for the fuel given by the mainjet. Now I have cured my Lady only for 90%, because my piece of foam must let pass more air then the OEM-piece, once the original piece in my possession I am completely sure that I will have back the Lady I knew for 12 years now !

Of course, when I leave that foam out of the air-intake, and I would compensate by changing the mainjets into bigger ones, then I think it would be a fantastic improvement o power for my GIRL, but then, I am jealous on you American guys, as you don't know how happy you must be that you live in a country with so many bike-specialists.
In Belgium I do not know any good craftsmen with a testbank to realise this, and then we don't speek about the cost of such operation : several times changing jets + DYNO's before the right mixture is obtained.

Another small difference : our pilotscrews are NOT D-shaped, they are directly with X (Philips-screws)

My headlamp is also fifferent : real glass + different mirror (not so bright) and with 2 lamps into the headlamp : 1 H4 bulb and 1 small 5W bulb that is our standlight.

That is the main reason of all these differences, because we are different nations with different laws, Germany is real severe (and AUSTRALIA also from what Woody said), and therefore some export-products have to be adapted to fit into that exportmarket. It s a pity, but it is politics......

[FLATSIX]

About my K&N filter : when at the time putting it in I did not feel changements because I have also put the pre-filter in it : it seems that it is like stock when you put the 2 together. Without that prefilter I am sure that my bike won't run anymore : TOO MUCH AIR.

I leave it in - has costed money and it is almost the same airdelivery as stock.

[Anthony]

hey FlatSix,

how is your status now ?
if i can help you out :
I have a
spare K&N filter,
a hondaline filter and
a Factory Pro Jet kit layout around,
and i am only 70km away.

send me a mail if you want to meet during the weekend.

Cu,

Anthony

[Madmike]

North American bikes use CV style carbs with #100 mains and #35 slow jets (stock)

[FLATSIX]

What I don't understand is how Honda manage to make so many different carb-versions with different jets and airsupplies , but at the end they all must give 98 hp.

I am convinced that on my European version when the air-inlet is fully open (without the famous foam) and I put larger jets in it then there must be a considerable gain in horsepower - or am I wrong here?

Does anyone have experience with this?

[Madmike]

I see that Lamonster tried airbox mods on a US bike and couldn't jet it out.  

http://www.valkyrieriders.com/shoptalk/jetting.htm

Here is some interesting info:

http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,lower_rpm_engines.html


http://oldmanhonda.com/MC/Rcarbs.html

[FLATSIX]

Hey Madmike,

Thanks for that good reading stuff about carbs and tuning up !!

I have print it and will read this each time I am on my cabinet till it's in my head.  Tuning is a matter of experience , skill and patience (+ money !).

It cannot hurt me to get any smarter 

[juliao]

Hello.. I'm on my second valkyrie with this same problem. Foam from airbox cover vanished away. Anyone knows where can I buy a new one? Thanks

[Harryc]

Apparently you could not get just the foam as of 2009 so I doubt 2016 would be any different. You'd need to order to complete cover as the OP did...or make your own foam piece. You do have a European Valkyrie right?