Fcr41mx

Discussion in 'Thumpers' started by MotoMike, Apr 30, 2005.

  1. MotoMike

    MotoMike Washed Up Desert Racer

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    FCR41MX. Is this carb suitable for a 640 ADV? Anyone? Creeper?
    #1
  2. ChrisC

    ChrisC Amal sex?

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    Both the FCR41 and FCR39 have been successfully transplanted onto the LC4.

    But do it at your own peril... :pope
    #2
  3. MotoMike

    MotoMike Washed Up Desert Racer

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    So the FCR41 and FCR41MX are one and the same? Is $495 a good price for a brand new one?
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  4. Mack

    Mack Gone, but never forgotten. RIP, Mack...

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    Yep, these carbs are pretty spendy! These carbs can be ordered with custom jetting from Sudco or Pro-Flo. If you get one that doesn't come equiped with an OBEKR needle, you will need one of those as well, and I would get the IMS screw adapter, that will allow you to adjust it by hand. The pump squirt is a bit much for the LC4 motor, there is a mod that lessens it on KTMtalk, or you can install a Honda diagprahm. (Check with Arch on this.) If you have an 03 you will need to decide if your going to get a TPS version or not. Another option to save some money is the non-MX FCR39/41 version.

    Check these guys for prices, as they normally have the lowest price on average, or at least a good price.

    http://www.pro-flo.com

    The Keihins can be a tight fit, especially the MX version, but they do fit. The accelerator pump gets really close to the pipe, especially the Akrapovic.
    #4
  5. lvdukerider

    lvdukerider Las Vegas Nevada

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    I installed the plain old FCR41 on my 00 Duke II over a year ago and am very satisfied with the results. That also sounds like a reasonable price,its about what I paied for the Sudco kit with the cables that dont fit. Are you talking new or used? I think the MX version has the hot start,TPS, and a shield where the cables attach but I diddent need all that and my plain jane FCR 41 works great it really woke up the motor and I had already done all the mods to the stock BST 40 which I diddent have any complaints with I just wanted to see what the big diffrence was. (big diffrence) The only drawback that I have found is she does suck more gas.
    #5
  6. creeper

    creeper Still alive...

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    It's OK Chris... one must follow their own path to enlightenment. :evil

    Were I to stray from the true path... I would opt for a 39 FCR. Throttle response is superior to the 41 and snap is where it's at in the dirt.
    #6
  7. Mack

    Mack Gone, but never forgotten. RIP, Mack...

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    If I hadn't picked my MX version up in a group buy, I think I would have tried to save some dough, and gone with the non-MX version on my pre-03 bike.

    Actually if I was to do it over, I think I would spend the money on suspension revavling and springs, and wait for a used FCR to come up on the market.
    #7
  8. MotoMike

    MotoMike Washed Up Desert Racer

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    Thanks for the input. Someone is selling one on ktmtalk...sez it's brand new. For whatever reason he is parting out a brand new SX, didn't say what cc. So I guess my question has been answered, the "plain" 41 is slightly different from the 41MX, correct?
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  9. Mack

    Mack Gone, but never forgotten. RIP, Mack...

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    The MX has some features for "Hard core" dirt use, IMHO, not really needed for an ADV, but nice to have, though they increase the size of the carb.

    MX features? I'm no expert, but off the top of my head: Baffled bowl, extra vents, options for hot start and TPS. Integral ACC pump (to the casting) and enclosed throttle cable bellcrank, keeps dirt out and thus reduces wear a bit compared to a non-MX, tuneable ACV air cut valve IIRC, etc. I'm sure I'm forgetting a bunch, but me belly is empty, and I'm feeling tepid! :kbasa
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  10. DevDel

    DevDel Been here awhile

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    If you don't have a '03 or newer high flow exhaust, the accelerator pump will hit the exhaust.

    The 41 will still have plenty of snap & torque, and it's what KTM chose to put on the SXC, rather than the 39 of the 525 MXC & EXC.

    Dev
    #10
  11. Renazco

    Renazco Formerly AKA Boejangles

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    Welcomomen to the land of low end grunt, now we're gonna nickname you wheelie Mike :lol3
    Seriously though, the 41 will be a nice snap for your bike. You changing the pipe as well??
    #11
  12. AusieRob

    AusieRob Just Gas It!!

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    What's up Mike... need more snap to get past those pesky KLX300's on the trail.. :poser
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  13. meat popsicle

    meat popsicle Ignostic

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    he's got an IDS2 - might need the race core eh? :nod I got's one to trade for a quiet core. :deal

    anyways, from all I have read, I would second creeper. the FCR39 would be better throughout the powerband, especially low and midrange. Its what KTM uses on the 660r bikes.

    of course if your deal is on the 41 then maybe you can live with it. if its not the carb for you it can always be sold. isn't $500 the new price? MotoMike, you check Sudco's price on that carb?

    http://www.sudco.com/

    http://www.sudco.com/catalog105/087-089.pdf

    Looks like the FCR39-MX is $593 (not incl. install kit)

    The FCR41-MX price isn't listed (blanked out) but it should be around $620 (not including install kit)

    Did you ask flanny about the Mikuni TM40? Its a pumper, he installed it on his 640a way back when... Its $289-318 (not including install kit)

    ps - Sudco has deals on ICS dampeners right now - and they make an istall kit for the 640! :evil anyone have any experience with the ICS dampener or products? :ear $280 for the whole setup!
    #13
  14. Rideguy

    Rideguy Kamikazi on one wheel

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    :hair FCR39mm jetted to suit will work great, so will the FCRmx41mm. Last year we got our 41mm's shipped and jetted for around $465 U.S.D. through the group buy which I arranged from Sudco.

    Make sure you are putting the carb on for the right reasons!!! Power gains are minimal, fuel consumption is greater. That being said this carb is Awsome for big jumps, and whoops!!!

    My Mikuni BST 40mm was great on the street, but for Safety reasons I went with the Keihin pumper carb to prevent fuel delivery failure in extreme conditions!!! So if your not going to Bump and Jump your bike stick with the BST 40mm. I.M.H.O.

    :pep Don't get any ideas Meat... I still say the 41mm belongs on my tweaked out LC4/SXC!!!!! 39mm's for Adventures/Ralleys/525's Not for the Power Hungry that ride W.F.O.T. on 620's!!!!

    :tb
    #14
  15. meat popsicle

    meat popsicle Ignostic

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    :dunno great post Ridefella! I ain't huntin' ya :D Had a great time in the other thread. Hope there is something we disagree about in the near future! :thumb SXC eh? ain't that the stock carb? :evil

    FYI, from what I have heard MotoMike is the whacko desert racer type. He might actually find that sliver of the operating window that I hear said taxes the BST. :smooch
    #15
  16. Rideguy

    Rideguy Kamikazi on one wheel

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    :velvt

    Meat, My 03 LC4e blew up last year and I replaced the top end with an 04 SXC, and FCRmx41mm with no throttle stop.... What a boost from the 03 high flow head!!! Cast shape is different too...

    I'm not stalking you.... Really
    :ymca
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  17. meat popsicle

    meat popsicle Ignostic

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    Phew!

    glad to hear the fcr is giving you what-for ridey!

    cast shape? you'll have to speak with creeper aboot that stuff; he's the engine feller.

    PS - say aren't you the feller who knows the secret dirt on Vancouver Island? :evil

    PPS - all my family is Canadian, they just popped me out in this dog-forsaken pit of a country due south of ya... :arg

    NO! They didn't go far enough to get me into Latin America :cry Just to Seattle, which is a pretty cool town. Now I am in the Bay Area and I say it pretty much sucks (next to zero dirt).

    Hope Parliament figures out their regs soon so I can apply for my citizenship and talk the wifey into Vancouver BC - that way I can harass the shite outa Loaded all the time :D
    #17
  18. Rideguy

    Rideguy Kamikazi on one wheel

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    :hairYo Meat... Some good humor here.. My folks are from the U.S. and dropped me out here...

    :yikes I'm not Thee from Victoria with knowledge of the Secret dirt..... But I am a Kootenay Breed with knowledge of Sacred Singing dirt :pope

    :jose Got some of Loaded's Risers and talked about a ride sometime since I have not yet gone Costal!! Let me know if you Fella's ever line up a ride there and I'll bring my 16 tooth C.S. and Check out the West Side for a while....

    B.T.W. A guy who ride's with a BST probably has a KLR he can't let go :poser

    I'm such a "Heathen" :flip
    #18
  19. meat popsicle

    meat popsicle Ignostic

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    Smart folks there bud. My family is from Cranbrook and Kimberley - over in them there Kootenays... :evil I'll have to ask my cousin 'bout that Sacred Singing dirt.

    you going on his loadedpalooka ride? think they said september. i can't, but i'll be in vancouver in November (around US thanksgiving).

    KLR? never had the pleasure. those folks in the KLR thread seem happier and have more fun than all others... :smooch
    #19
  20. Rideguy

    Rideguy Kamikazi on one wheel

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    :oscar Too funny... I went to Highschool in Kimberley, lived out by Skookumchuck all of my life at the base of the Rockies.... Wouldn't be surprised if we knew some of the same people....


    :ricky Loadedpalooka ride.... Might just be an idea since it would be the most beautifull time of the year to hit the Coast!!! You should try and make it up!!

    I'm off to start a new post for us.. Come check it out if you dare....

    :jump
    #20