950 CV carbs w/ 2.5" K&Ns/H2W jetting

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by Navin, Apr 20, 2012.

  1. Navin

    Navin Long timer

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    After suggesting pods on the CVs a few times to others, I took the plunge. I was fully expecting my previously prefiltered H2W jetted perfect bike to be a mess.

    It isn't.

    I had a set of K&Ns off my FCRs on the SE that I replaced with foam Unis sooo...

    I have the ever so slightly lean feeling at 1/8th throttle cruise but the bike started right up, idled smoothly and at WFO it just runs great. I'm a jetting pinicky rider. I'll ask Ken about my little issue but I can live with it as is if I must. I'll play with the mix screws later after the air filter oil dries.

    The mouth of the carbs is slightly tapered and a little thin IMO, so I added a safety wire retainer though they were pretty secure. Maybe I'll play with the old airhorns to fit a better clamping area someday. It is as easy as popping the seat to mess with it now!!! :wink:

    Who the heck said this wouldn't work back in 2004??? :ear

    Man, am I sorry I waited this long to try it! :doh

    [​IMG]
    #1
  2. mousitsas

    mousitsas Long timer

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    Interesting info Navin.

    Could you please give more details on how it runs and (if you remember) what is the diam of the carb intakes.
    I am especially interested on how they perform on top gear roll on and if you notice any difference on the minimum revs required to pickup while doing that.
    Also, what is your exhaust setup?

    I am sure fueling could be 'adjusted' by wrapping them with a filter skin of some sort if they prove to cause lean running or if they need more vacuum. After all, if FCR's are running with pods, why not the CV's?
    But before I do the same, which I would like to do to get rid of all this crapola under my tank, I would surely want to see AFR readings. Any chance of doing that at some point???
    #2
  3. Navin

    Navin Long timer

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    I'm going out to ride it again now. Runs pretty good, has that ever so slight leanish spot at 1/8th throttle, pulls to the limiter just fine, front wheel floats off the ground in the low gears. It idles smoothly, I didn't even adjust anything yet! I'm within a couple hundred feet of sea level, 2-1 FMF Q4, H2W jetting for a prefilter.

    I'm kickin myself for not trying this years ago. :lol3

    I had a few hours to kill nursing a little injury and the parts were in front of me, the perfect storm. I expected to be chasing brass for weeks. This is a no brainer IMO. I used the 2.5" K&Ns that were on my FCRs on the SE950.
    #3
  4. Navin

    Navin Long timer

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    Took it for a good test ride, lean on the mains. Everything else feels fine. Should be an easy fix. Now, what size were those H2W mains I had in there?
    #4
  5. mousitsas

    mousitsas Long timer

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    148 and 152

    How about intake sound level?
    Why don't you try to see if some sort of filter skin works rather than changing the mains?
    I would also try to over-oil the KNs (just for a ride) to see how that changes things.
    #5
  6. Navin

    Navin Long timer

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    I'm going to try wrapping them with something oiled to see if that does the trick. Intake noise is increased for sure, not as clattery as my other bike with FCRs but louder than with the box/prefilter. Nothing I can't live with, not deafening for sure.

    I'd like to reuse the intake horns, that will be sweet. To just pop the seat, reach in, twist and remove each filter? Nice!
    #6
  7. mousitsas

    mousitsas Long timer

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    Of course a sound clip will be mostly welcome, sometime...
    If you trust that the intake snorkels are secure in the way they attach, then you will find a way to fix the pods on them. By the way, what is the outside diam of the snorkels? I am wondering if I can find big enough pods to go over them. Another way, would be to cut the upper lip of the snorkels and fit the pods over them, if possible. But I do like the funnel shape of the intakes and what they do to flow smoothness.
    #7
  8. Navin

    Navin Long timer

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    They have a few lumps in the body to allow the two air ports to breath. It'll be a little task to get them to work but not impossible. I'll keep you posted as I mess with them.
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  9. Navin

    Navin Long timer

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    I oiled up a pair of dirtbike foam filters and wrapped the K&Ns. Midrange is hitting much harder and she revs out cleaner, nearly perfect. At high RPM if I hold it steady it still has a slight hunt, not that I ride it like that but just to see how it feels. Looks like a step up on the mains will called for in the near future. Running great right now, it will only get better. :evil
    #9
  10. mousitsas

    mousitsas Long timer

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    Could you post the serial numbers of the KN's please Navin? You could maybe put the stock jets in (155 & 160)
    #10
  11. Navin

    Navin Long timer

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    I don't have a number, they came with my FCRs for my other LC-8. I replaced them with Uni pods in 2.5" X 5". The K&Ns are better for now due to the top plastic that I can safety wire against to prevent them blowing off.

    I just looked for my old stock jets, not having any luck yet. :lol3
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  12. mousitsas

    mousitsas Long timer

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    Keep looking!!!

    I think the serial number is the one shown (but the pic is not clear enough) on top of the pods.
    #12
  13. K2m

    K2m ....58....

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    This would work over your trumpets. These trumpets are an important part of producing HP.

    You also have the benefit of oiled foam

    I think your mad doing this without the security of a wideband but good luck:wink:

    If your interested let me know and I'll find a link to them.

    [​IMG]
    #13
  14. Navin

    Navin Long timer

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    :eek1 Good eyes! I needed a flashlight to see it in my well lit and spacious garage!

    Looks like "D03384" by the best I can read it.

    K2M, I hoped you might wander in here! If you can find those part numbers without too much trouble please post them!

    Wideband would be nice but I do all my race bikes by trial/error. The CVs aren't as easy as the FCRs I usually deal with but I think it is already really close as it sits.

    Mad is about as nice a name as I've been called lately! :lol3
    #14
  15. Navin

    Navin Long timer

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    The flat lip is the problem, 4" diameter.

    By trimming that off, still leaving the horn shape, you can probably slip the 2.5" pods on it and it has the benefit of tapering outward so there would be no need to safety wire over the top of them. It gets slightly wider as it gets taller.

    Uni 2.5 X 5" is what I have on the FCRs. :evil

    I don't have any concerns about how the lock in. I've never seen mine move out of place in years and pounding I've put my bikes thru so I doubt there will be an issue, but a loop of wire would lock it in if it feels loose with the pod on it.
    #15
  16. Chuckracer

    Chuckracer Jerkus Maximus

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    This thread is FULL of win!! :clap
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  17. Navin

    Navin Long timer

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    I'm all in now, :lol3!

    The trumpets are ground down to accept the 2.5" K&Ns for now. I ordered another pair of 2.5 X 5" foam Uni pods.

    I tried them both with and without the outer foam filters I rigged up, no difference. Without the covers it is very lean on the main, with it (richer) is better. Almost "good enough". I bet adding fatter mains will mess up the perfect low to mid, she pulls hard till the main at WFO, then tapers off a little.

    I'm scanning thru my brass collection as I type. Anyone know off hand if the mains are the same as a FCR???

    *** EDIT, not even close by the pics I found. I've got a load of those!

    Thanks!
    #17
  18. K2m

    K2m ....58....

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    Completely different.............. but you know that :lol3

    http://www.uniflow.com.au/contents/en-us/d135.html

    They are NOT !!! the same as a 38mm PWK Airstriker. Two Stroke GasGas KTM etc.

    [​IMG]

    ................................PILOTS .........CV mains.......FCR/PWK Mains..........Pilots..... pilots................................................

    FIXED !!! :lol3
    #18
  19. veetwo _tls

    veetwo _tls RENOVATIO:

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    the K&N's are #RU-2780


    .
    #19
  20. Navin

    Navin Long timer

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    Is that correct now? Aren't the CV mains in the second section with a screwdriver slot in the heads?
    #20