XR650L hotcam

Discussion in 'Thumpers' started by domains, Jan 15, 2013.

  1. domains

    domains Been here awhile

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    Im a licensed mechanic( im a second generation know it all)

    I set cam .15 intake .20 exhaust, stock cam is 10mm intake .12mm exhaust


    but now I hear it rattling more now

    after cam brakein can i set back to stock?:norton

    Its a new motor... piston crank all new, everything's new
    #1
  2. mcma111

    mcma111 Long timer

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    How many miles on the new motor??

    Did you confirm oil flow to the top end??

    If Hot Cam says .15 and .20 then that's the spec.
    #2
  3. mcma111

    mcma111 Long timer

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    BTW...

    This belongs in the Thumper section
    #3
  4. domains

    domains Been here awhile

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    Thumper might of helped one piston but one or 8 pistons kinda the same no? lots of oil flow

    Why is the settings almost double with hotcams?

    megacycles settings just as high?

    i think its just because the hotcams are not polished thats why they want low rpm brakeins

    whats your thoughts?

    after brake in low idle set to stock?
    #4
  5. mcma111

    mcma111 Long timer

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    My Mega Cycle cam has .004 and .007 specs.

    I don't know about the Hot Cam other than more than a few folks that have installed them in their XRL's have regretted it. Some have had good luck.
    #5
  6. domains

    domains Been here awhile

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    Mega cycles are polished?

    I had the urge to 300grid wet sand paper them but thought il just let idle 20 mins like specs

    but i know my stock cam didn't rattle as much

    brand new rockers less then 2 hours on them so i know its because .15 or .20 is loose

    lots of oil pressure

    didnt ride bike yet... just let it idle 10 mins cool down 10 more mins and checked valve clearance no change
    #6
  7. domains

    domains Been here awhile

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    I bet the trick is just polish the hot cam and you got yourself a mega cycle

    without spines
    #7
  8. elsalvadorklr

    elsalvadorklr southern xr rider

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    dude no

    good luck...pot metal versus high quality treated steel...

    the polishing is not the difference

    do not deviate from what hotcams says, for tolerances, keep them loose and check often...if you start seaing that you git whacky valve lash specs then well start thinking about a replacement cam and hopefully not rockers...

    enjoy it as the performance for $$$ value is high since all you do is plop one in with a new gasket...all other performance cams REQUIRE hard faced rockers that are treated to tolerate the HARD AS HELL CAMSHAFTS...

    something to think about

    christian
    #8
  9. kubiak

    kubiak Long timer

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    its been awhile but dont you keep the rpms up when breaking in a cam? did hotcams say to let it idle?
    #9
  10. elsalvadorklr

    elsalvadorklr southern xr rider

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    word, something like 3krpms steady? lubed up?
    #10
  11. mcma111

    mcma111 Long timer

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    CW says 2000 RPM for 20 minutes. Of course I never did any break in with all of the Mega Cycles cams over the years and I've NEVER had a problem with their products.
    #11
  12. elsalvadorklr

    elsalvadorklr southern xr rider

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    for the hotcam or our cams?

    anywhoo
    #12
  13. mcma111

    mcma111 Long timer

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    CW's cam
    #13
  14. domains

    domains Been here awhile

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    The surface of the hotcam is rough, like they sprayed them for rust protection

    guess il leave them loose for now

    thx for help

    Maybe the bad luck people had with hot cams it too much lube when installing... like over use of thick STP that could plug the oil holes on cam lobes
    #14
  15. elsalvadorklr

    elsalvadorklr southern xr rider

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    nope, thats a coating they put on the factory to help breakin

    after say 200miles or so youll see the nice shiny metal

    same with our cw cam, they come coated then clean off

    again

    leave them loose forever...,not just now...lastly the reason for those lash specs are because of the ramp angles, etc of the lobes, they need more space

    others can explain this better...

    for example cws cam recommend a TIGHT .10mm on both sides...
    #15
  16. domains

    domains Been here awhile

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    elsalvadorklr Are you saying I should of cleaned off the coating?

    Instructions with cam only gave valve clearance, I learned about the 20min brake in threw Google searches
    #16
  17. elsalvadorklr

    elsalvadorklr southern xr rider

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    no! maybe Im not explaining things well

    I think you are overthinking every single issue and are not understanding some basics

    the issue with hotcams is they sometimes have bad batches of disimilar metals...what happens(for those that suffer from bad hotcams) is they either start pitting and or start pitting the rockers...if either metals are dissimilar or one is much stringer than the other guess what? one starts getting eaten..thats all I was trying to express.

    lastly that coating is designed to be used up after a certain amount of hours...its DESIGNED to shed off...if the cams didnt have that coating it woukd be much easier to damage either the lobes or the rockers...

    oh about the cam lube causing the weep holes to get plugged up...

    look up centrifugal rotation or anything related to rotation...you could plug the damn thing with wax if you want, the force of the cam spinning at speed is enough to squeeze out most anything... so no excess lube will not plug up a hotcam and cause failures...

    I poured STP all over my cam and rockers...its part of the reason my old clutch gave away...but my cam sounds fine and looks great too...

    however I dont have a hotcam...so apples to oranges:D
    #17