New bike, new cobras, carb issue ........

[Pal]

Hi all. I am  Pal , from Ireland. This is my first post, and i am a new owner of a 98 valk UK model for a month now.
I got the bike with standard pipes on, ride it for 2 weeks, then installed a set of used 6x6 cobra pipes with baffles.
i had a hole since i got the bike between 1500-3000 rpm , and i get only arround only 20 MPG. I made my mind after reading a lot of things on this site     and removed the carbs to see whats in it. First i found out (after i ordered one already)  that the airfilter is  a K&N with prefilter. I really hoped that the carbs are dirty and a cleaning will solve this issue, but they where OK.
when i removed the jets i find:  slow 35   , main 78.  I read a lot about changing the slow jet  to #38 but why is the main only #78
I read it that most valks run with 100 or bigger main jets!?

[9Ball]

the mains you have were standard for the European Valkyries....most likely for your European fuel economy or emissions standards.

Might want to get a Factory Pro (that's the brand) and then you will have the larger jets and adjustable needles.  This will improve your performance for the Cobras with the K&N.  The stumbling you are describing is a typical symptom of a lean condition.

With your current setup you are running too lean and risk engine damage.  You need to supply more fuel (richer mixture) to account for the increased air flow that the K&N and the Cobras provide.

[Pal]

Thanks for the quick reply. What stage kit  should i get? i found this on factory pro site
CRB-H78-1.0  Make SURE that you provide the YEAR and COUNTRY - many non USA bikes used 78 main jets.
So i guese there is different kit for USA and Non Usa Valks!?

[9Ball]

you might try getting in touch with Dag....he's the expert on Euro Valks.  He can tell you exactly what you have and what you need.

http://www.valkyrienorway.com/

[sandy]

I agree with connecting with Dag. One way of getting more fuel into it is to open up the pilots a bit. The American bikes run the pilot screws 2-2 1/2 turns out from being lightly seated. This richens up the idle mixture but also adds more fuel throughout the RPM range. IMHO: Sell the Cobras.

[The Anvil]

IMHO: Sell the Cobras.

IMHO: don't do that.

[9Ball]

Thanks for the quick reply. What stage kit  should i get? i found this on factory pro site
CRB-H78-1.0  Make SURE that you provide the YEAR and COUNTRY - many non USA bikes used 78 main jets.
So i guese there is different kit for USA and Non Usa Valks!?

I don't know if the carbs on the Euro models are different than the USA bikes.  Can't make a recommendation without knowing.  Hopefully Dag will be able to help you.  I think the higher stage kits were for more modified bikes besides just Cobra pipes and K&N.  Factory Pro will also be able to make a recommendation.

[Pal]

Thanks Guys !     I just got the cobras, and i love the look and the awsome sound. The bike wasnt runing good with the original pipes neighter, so i wont feel the difference  
I wrote an email to Dag. And let you know, i really dont get it if the fuel is not enough , how can i get only 20 MPG and if  the mains are smaller then the US model. I wrote to Factory Pro as well. I keep u posted

[Bone]

i really dont get it if the fuel is not enough , how can i get only 20 MPG and if  the mains are smaller then the US

If your engine isn't running efficiently it's not producing as much horsepower as designed. That makes you run longer in lower gears, longer with a choke, etc.

[Pal]

Ok. I wrote to Dan in Sweden, he has a US spec bike, so dont know much about Euro carbs, but he gave me a guys contact in Germany, i am waiting for his reply. We getting very international here 
I got a reply Factory Pro, Marc put on a Euro kit on the site, i think i go for that , but wait till i get the response from the German guy. I see on FP site they have a 4 degree ignition trigger wheel. Would you guys recomend it? or any other brand
Thanks

[9Ball]

the 4 degree wheel is typically for the Interstate and the 6 degree is for the Standard/Tourer model.  I've never been a fan of the trigger wheels but that is only my opinion.  You might want to go slow with your mods and see if you can address the fuel mileage issue first before getting too carried away...too many changes at once can cause a lot of headaches.

Good luck with your project.

[Pal]

I  wont change the wheel yet, but like to know if it wort to get it, so if order the jet kit, its cheaper with the wheel.

[Pal]

I am very confused now. I got the reply from Factory Pro, they sent me the contets of the EURO jet kit. It has #38 slows as , and 2ea #78 and 4ea:#80,#82,#85,#88.    Now if i use the same  the 6x6 cobra pipes, and K&N filter as all US spec bikes, why do i need smaller main jets than you guys in the USA???? I tried to find out if there is any difference internal of the carbs, but no infoi so far......     
Getting crazy     

[9Ball]

The 78s are for the front carbs (1 and 2) and the larger jets are for your back 4 carbs (3,4,5 & 6).  To optimize performance the jets selected should be based on dyno results for your specific setup (K&N or factory filter, etc.).  You might ask some on the Euro websites what others are using to save yourself the experimentation.

I'm guessing that your carbs are different than USA bikes.

[Ricky-D]

The different sized main jets reflect FP's convoluted thinking regarding the air box design and FP's answer to same.

If there actually is a problem with the air box design.

Some have modified the air box with unsatisfactory results.

It doesn't seem reasonable to me that each carburetor needs a different jet depending upon placement on the motor.

It would make more sense to me, to attack the problem (if one exists) at the source. The air box.

Of course, then FP would not have a horse in the race. No sale!!!!

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[Pal]

/yep i get that. My concern is not the different main jets to the 2 front cylinder, but why would honda make a different carb for the EURO market?!? Why not only use different jets. And if they use different carb on the US an UK, Euro carbs, what is that difference, and what if i replace my carbs to US spec ones.....?

[Hedgehog]

Hi Pal. I'm in England but visit Ireland a lot...

Can I just say that most 'Euro' bikes were actually personal imports direct from the USA or Canada, so won;t be configured any different from bikes over the pond... The Reg Document should be able to tell you , although I tried the DVLA who managed to find out that my bike was Canadian...

When these bikes were imported EC regs were much less intrusive, so there is little chance they will have been changed...

HH

[Pal]

Hi Mate. Mine is deffenetly a UK spec bike, i checked the VIN number:
You can check it out here:
http://www.valkyrienorway.com/VIN%20NUMBERS.html
just clinc on link , at #2 Vehicle Description (variant)
See discussion on Variants
   


   

[9Ball]

So you see on the link for differences that the carbs and the exhaust (more restrictive) are different models on Euro and UK bikes...

http://www.valkyrienorway.com/MODEL%20DIFFERENCES.html

This explains the difference in jets. 

[Pal]

Yep, i got that, but i changed my exhaust to the cobras, witch is the same for all modells, so i just wonder what is the difference in carbs, rather than jets. Smaller diameter or what!?

[Ricky-D]

Naw, I think all the carburetors are the same, seeing that the Valkyrie is made here in the USA.

They didn't put a different carburetor on the California bound bikes.

Emission specifications are the main differences between bikes slated for different destinations and they accomplished that with peripherals. (smog controls, ignition timing and carburetor jetting)

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[9Ball]

Naw, I think all the carburetors are the same, seeing that the Valkyrie is made here in the USA.

They didn't put a different carburetor on the California bound bikes.

Emission specifications are the main differences between bikes slated for different destinations and they accomplished that with peripherals. (smog controls, ignition timing and carburetor jetting)

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The carbs have different ID codes...  Here's the text:

"European models use VPKON carburetors
UK models use VPKOS carburetors"

From the Honda service manual, US carburetors are either
VPKOA (97) except California, for Standard and Tourers
VPKOJ (after 97) except California, for Standard and Tourers.

What the exact differences are isn't spelled out, but it's interesting the number of different identification numbers for the carbs.  California bikes have a different code than the 49 state bikes, so there must be a difference otherwise they wouldn't have different designators. Hope this helps.

Maybe Kehin customer service can answer what the difference are...worth a call or email.

"Orma Divisione Motori di Antonio Congedo - Vico Piedigrotta,2 - 80122 Napoli Italy p.iva IT01031960527

tel.+39-081-660464 - fax +39-081-662073"

Or Sudco

http://www.sudco.com/

[Hedgehog]

Yet again I'm reminded that there are So many helpful folks on here - its reassuring with such an old bike...

Don;t know what I would have done without this kind of help.

Hope you get sorted Pal.

[Chillerman]

You may want to check out this thread http://www.valkyrieforum.com/bbs/index.php/topic,5344.0.html and/or contact FLATSIX. I remember he was going through a lot of problems with his European Valk running properly. I would check to see if you have that foam insert in the airbox first.

[Ricky-D]

Different codes indicate a different assembly.

I know two right off.

The Interstates have a different carburetor from the Standard and Tourer.

It's the slide spring that makes the difference.

Same kind of deal, but the main carburetor is identical I would say.

When you start to look at jets and needles there can be a mass of different combinations, all with a different model number.

I feel sure that mirroring the US model (non-Cal) with needles and jets would be equal to the US model.

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[tmfp]

Emission specifications are the main differences between bikes slated for different destinations and they accomplished that with peripherals. (smog controls, ignition timing and carburetor jetting)

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Not exactly so, an easy way to tell if you have a Euro bike or not is the lack of PAIR system. There are no holes in the casings for it, implying different castings for different markets.

[Pal]

Thats right TMPF!  i forgot about that. It has to be something otherwise why would Factory Pro make 2 different kit, they could just sell me the US kit for the same money...

[Irish-Valk]

Hi PAL, I've been following your thread and find it very interesting, got a lot of information from it. I'm interested to hear if you had any success wth your problem. I have a similar problem, perhaps not quite so bad. I imported an American '99' interstate into Ireland 4 years ago with low milage (21k), has a set of Cobra's and a K&N filter. It ran very rough and smothered itself if left idling for a few minutes, terrible in traffic jams. Was only getting 27/28 mpg. It would blacken the plugs, cut out and when I would get it going again it would run like a dog, missing and backfiring for about 4 or 5 minutes until it sorted itself out. Took it up to Crossans in Newry and put it on the Dyno, they dismantled the carbs. Replaced the 38 slow jets with 35's and replaced the 100 main jets with 90's. they put in NGK Iridium plugs. Must say the bike was greatly improvement but far from perfect.

I still get only 30/31 mpg. The bike smells very rich (I can smell it when i'm stopped in traffic) and it still doesn't like idling for long periods, its prone to misfiring and cutting out. That said if I can avoid being in slow traffic it's great. The bike never needs the choke to start, even in the coldest dampest days and it always starts first time on the button. The folks on this site claim to be getting 35/40 mpg and that's with their smaller US gallons. When converted to our gallons that would equate to more like 40/45 mpg (not a chance with my Valk). My bike had all the emmission controls gadgets required in the US, so a few months ago I did the 'De-smog' as suggested on this site (removed all the unnessesary bits and pieces). That did give me some more improvements but it's still not 100%. Hence I'm very interested to see how you get on. I'm tempted to dismantle the carbs myself (if I ever get the confidence) and revert to the standard jet sizes, but when I read on the Norway link in your thread it suggests a different jet size for Europe than America, I suspect that's because the octane content of pertol in Europe differs from that in the US (European petrol has a higher octane content). Now I'm confused.
I wish you the very best of luck with the bike and with getting this problem sorted out. I would  love to know how you get on with it.

[wolf]

This maynot solve your problem but i have a 97 valk and it has the gutted version of the cobras and it seems to be running fine i run high test only in her but after seeing some of the problems u are having was curious to see what your octane ratings are oveer there. I run 91 octane and she roars with no cut out and plenty of power. maybe this will help yours

[Pal]

Hi Irish -Valk.
I am stuck at the moment, dont really know what size of jets to get. You wrote, that u tried a few configs. Would you mind you give me a lend of those jets you removed, so i can make a little experiment with them?

[Ricky-D]

Honda offers different head gaskets for the Valkyrie.

The thicker head gasket affects compression ratio.

Like motors with different compression ratios have different needs.

This is especially true when looking at carburetor jetting and associated items.

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