BMW 336 cam

Discussion in 'Old's Cool' started by Anorak, Oct 15, 2008.

  1. Anorak

    Anorak Woolf Barnato

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    I have a part #11311337843 sitting here brand new with the matching oil pump rotor. From what I can tell it fits /6 with points ignition. I'm under the impression that at some point in the /5 era the seal size changed. Okay, it looks like this is the large seal version. Anyhow, anybody have an idea of what it's worth?

    p.s. It looks like the small seal and post 1980 electronic ignition versions are available from Moteren Israel for 229 and 149 Euro respectively.
    #1
  2. Hawk Medicine

    Hawk Medicine Coyote's Brother

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    As of a month ago, those parts were available through BMW USA.

    Contact then and check the price or look it up online.
    #2
  3. Crush

    Crush Been here awhile

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    What is the significance of a 336 cam?

    Is it a performance cam?

    Thanks, Dennis
    #3
  4. kbasa

    kbasa Roubaix! Super Moderator

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    :nod
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  5. Crush

    Crush Been here awhile

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    Is a 336 cam something I should consider during my rebuild of my 1974 R75/6?:evil

    FB, when you figure out what you have and what you want for it, would you drop me a PM?

    Thanks, Dennis
    #5
  6. JimX

    JimX .. .

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    With an otherwise stock engine, the major benefits of a 336 cam addition will be poor idling and decreased gas mileage.
    #6
  7. pbansen

    pbansen Hosehead

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    The operative phrase being "otherwise stock". With the correct setup, the engine will run extremely well and gas consumption will increase only modestly. I had a blueprinted '82 R100 with the 336 cam, Mikuni flat-slide carbs and Bub exhaust and it ran like a top and got 36-40mpg. Good power, too...

    Wish I had it back!
    #7
  8. Hawk Medicine

    Hawk Medicine Coyote's Brother

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    Uhmmm... Maybe a more complete answer would be halpfull here...

    The 336 is designated as a "Sport" cam. It has much more overlap than the stock 308 and therefore benefits from and allows higher compression ratios.
    It also produces it's (Greater.) power higher in the rev range.

    So... You get this kool kinda rumpa-rumpa idle but off-idle performance is pretty flat untill the cam "Comes on" at maybe 3000 rpm. After that the bike takes off and will produce usable power beyond redline. The cam has lots of overlap, so if youre running lots of compression (And you should be with the 336!), the engine "sees" lower compression at low revs. Thats a good thing.

    A 1050cc or larger Airhead will really work well with this cam because theyre already producing 'adequate torque' down low and the cam allows the bike to hammer out the horses up top.

    A 336 is a great cam if you install it in a bike intended for cross country trips or high RPM backroad burning . The trade off is that these bikes are not very satisifying to ride around town. Not to me anyway...

    Most of the really good running bikes that I remember that ran 336 cams also ran Hi-comp pistons, big intake valves, dual plugs, light flywheels, balanced, and were very carefully set up. Add a big bore kit and some porting and youre in Airhead heaven untill the engine coughs up its guts!:rofl

    PS: If youre really serious about replacing your cam, MI offers a 324 Sport CAm that I've heard very good things about. It'll support some compression increase but the lower rpm area is fatter. If I drop a dime on a cam, thats the one I'm going for.
    #8
  9. walkingbear

    walkingbear Lets Play Chicken!

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    I have a 336 cam that I didn't installed. Instead I
    replaced my FD with 37/11 ..

    No only will run like a bat out of hell.. it will save money
    by not having to rebuild the entire motor.

    I have one over pistons in my 79 R100T now..not a 1050 but pretty close 1028 rebuilt 40mm bings free flowing exhaust and drilled airbox.

    Biggest difference is the teleflex front brace, upgraded springs in rear (progressives), heavier triple tree, oil cooler and
    heavier fork oil.

    Now, need to figure how to stop the beast faster!!
    #9
  10. Crush

    Crush Been here awhile

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    I'm already in my engine, hence the questions about the 336 cam.

    Dennis
    #10
  11. Hawk Medicine

    Hawk Medicine Coyote's Brother

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    As I tried to say....

    The 336 isnt that great a cam all by itself but if youre building horse power through higher compression, head work and different carbs, it can easily be part of a winning combination.

    Install high comp pistons , freshen and dual plug the heads, add in an electronic ignition, rebuild your carbs and you WILL note a difference!

    Most guys who try it like it.
    #11
  12. Hawk Medicine

    Hawk Medicine Coyote's Brother

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    Chicago BMw will sell you a 336 cam for $157.00 and delivery of mine took two weeks, like everything else fom them.

    If you want to sell your cam and it's truly NOS, I'll pay you the cost of a new BMW cam, plus shipping, maybe a bit more 'cause it might save me a bit of machining.

    While the currently available cams don't have the small seal diameter or the points tip, it is possible to run the later timing cover with the current cam and benefit from the ability to use a bean can as backup or , with some machining, you can do the same thing with the stock smooth chain cover.
    #12
  13. wirewrkr

    wirewrkr the thread-killer

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    Actually, $157.00 is LISt price, so knock off 20% and save a bunch.
    But as far as I'm concerned, Chicago BMW takes WAAAY to long to deliver.
    Robert
    #13
  14. Hawk Medicine

    Hawk Medicine Coyote's Brother

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    Gadzooks!!! Youre right again...!

    A quick check of my receipt, tells the tale and I only paid $125.90 for that cam. Heck, for that kinda price I should buy another one! I fully expect these to be discontinued shortly and I will need one for the R-100 mill I've been saving.

    I don't like waiting for parts any better than anyone else but a 20% discount just happens to be 20% saved and sometimes I don't need my parts "like right now!" Add in your 'home field advantage' (:D) and we're playing in different leagues!
    #14
  15. Anorak

    Anorak Woolf Barnato

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    Are you talking about this. Maybe you mean a different Chicago BMW.
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  16. AntonLargiader

    AntonLargiader Long timer

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    Did you see the used one on IBMWR for $250? :rofl
    #16
  17. bmwrench

    bmwrench Long timer

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    "I have one over pistons in my 79 R100T now..not a 1050 but pretty close 1028 rebuilt 40mm bings free flowing exhaust and drilled airbox."

    I hate to break this to you, but "one over" (.25mm) yields a whopping 984.5cc.
    #17
  18. Hawk Medicine

    Hawk Medicine Coyote's Brother

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    Yeah!

    It seems as if theres a rumor going around that the 336's are no longer available, so some folks are willing to pay through the nose to get one.

    (Hey! Now THERES a market that ripe for the picking! "Found in an old dealers warehouse!!! NOS 336 cam. Discontinued by BMW but you can have this one for only $500. My loss = your gain!")
    #18
  19. RecycledRS

    RecycledRS Along for the ride

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    Who or what would MI be? Any info on the 324 cam would be good as well. Thanks, Bill.
    #19
  20. wirewrkr

    wirewrkr the thread-killer

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    No, the part number you have is for the 09/75-09/78 engine. It is NLA from BMW. The one I was taliking about at $157.00 and change is currently available and fits the 1979-1995 airhead engines. ALL of them.
    except of course the R65, it may bolt in but doubt it would run well due to the extreme angles of the followers etcetera.
    Robert
    #20