KTM 500 EXC - Converting to Cush Hub

Discussion in 'Thumpers' started by mdlafferty, Dec 14, 2016.

  1. davesupreme

    davesupreme grand poobah

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    got a cush for my 450 RFS bike.... if the sprocket carrier is seating on the hub hard like it's sposed' to, i believe it's actually 1/16" or so too wide. i believe the 6XX bikes that these were patterned from had a wider swingarm..... like a dumbazz, i first machined .070" off the brake hanger to make it fit.... then the brake hanger died, got a new one, and took the .070" off the brake side spacer, and everything was good...... measure w/the cush rubbers out, the carrier fits hard against the hub..... if it won't go in then, something's gotta change....
    #61
  2. miksu

    miksu Been here awhile

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    I remember some hubs/wheels being more tight than others, or maybe it is the swingarms. I have a gut feeling the current cast ones are not so tight, but the older welded ones have a bit of preload. Or maybe it is just manufacturing tolerances. Standard hard hubs need to be an easy fit for competition, no time to hassle with it.
    #62
  3. jwrover

    jwrover Long timer Super Supporter

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    OK...Silly Question warning!

    So I have a full Reklus kit on my '15 500EXC...I live about 3 miles from trail heads and can spend anywhere from 3 miles to 40 miles on tarmac before hitting dirt. Too many choices really!!

    Do I need to consider getting a Cush Hub set up? Or am I going to notice minimal rear hub wear with the proximity to trails and the Reklus?

    Cheers,

    John
    #63
  4. Kyron

    Kyron Purveyor of Thneeds

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    Depends what oil your using in the motor
    #64
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  5. Royce Cochran

    Royce Cochran was 2bold2getold

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    Well....that wasn't much help.

    Living in Ouray, I'm sure you're running knobbys so I doubt if you really need a cush hub.
    #65
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  6. vdlcinc

    vdlcinc Adventurer

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    Showoff...
    #66
  7. Proud Highway

    Proud Highway one hand waving free

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  8. critter731

    critter731 Adventurer

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    OK So what is the parts list needed to convert a 500 exc to a cush drive using OEM parts?
    #68
  9. an13

    an13 Been here awhile

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    Start by looking for 640 adventure hub.
    #69
  10. HiOctaneOverland

    HiOctaneOverland Been here awhile

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    Hi, I'm resurrecting this thread.

    Will a LC4 SuperMoto cush drive hub (rather than the LC4 Adventure hub) fit a 500EXC? And will it lace to a standard rim? Looking to fit a cush drive to a 2013 500EXC, but can only find an LC4 SM hub. Will it work?
    #70
  11. SRG

    SRG Long timer

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    The hub will fit. Don't know about lacing to your rim.
    #71
  12. Jasper

    Jasper Adventurer

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    KTM changed to a larger rear axle in there somewhere. I am not certain, but it seems like the 640's had the smaller axle.

    What I am certain of is that I can't get a 690 Enduro wheel to fit into the width of the swing arm on my 2019 FX350.
    Earlier in this thread somebody said that it is about 10 mm too wide. This seems about right to me.

    I have a 2003 LC4 625 SXC that has the smaller rear axle, and a cush hub from an LC4 Enduro The 2019 FX350 has the larger axle.

    I have looked through my own notes and found this:
    Rear Wheel: 20mm axle, fits all full size KTMs from 1994-2010
    Thus, it seems that the later 500 EXC needs a large axle hub, as do I.

    I will stay tuned.......
    #72
  13. SRG

    SRG Long timer

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    I think spacers and maybe bearings can changed or swapped - the 640 hub fits.
    #73
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  14. Jasper

    Jasper Adventurer

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    I need some help here. I don't know when the larger axle showed up...maybe 2013.....

    I have three of the small axle "sprocket carriers" and one from a 690 Enduro. I would really like to get an 18 inch cush hub wheel onto a large axle 2019 FX350.

    The small axle "sprocket carriers" bearings are substantially smaller in outside diameter than the bearings in the 690 large axle "sprocket carrier" so it looks like the bearings from the 690 won't be working for me on the small axle set up.

    What large axle bearings might fit into the small axle cush sprocket carrier?

    Some body says (circa 2015):

    "again, other way around. 20 mm used to be the norm at the rear. they went to 25 in 2012 and only on the SX, XC and SMR bikes. exc from '99 till now still have a 20 mm rear axle."
    #74
  15. SRG

    SRG Long timer

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    When I was struggling w/ a KTM wheel fitment/part compatibility issue the people at Munn Racing were helpful. I think they would know how to make what you have got work on your bike.
    #75
  16. Jasper

    Jasper Adventurer

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    Thanks for the suggestion.
    But, I had a really very disappointing experience with Chip Munn years ago, so I am unable to go there.
    I'll keep working on it.
    I may be on my own since there may not be much of a market for large rear axle (Race Bikes) cush 18 inch wheels.
    The motard guys are all about 17 inch wheels, and I am intuiting that the hubs are different for that application.
    #76
  17. SR1

    SR1 Going to America!!!!

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    Resurrecting this yet again. I have a line on a '99 640 LC4E rear wheel, will it fit a 2015 500 EXC?
    #77
  18. roookie1

    roookie1 Been here awhile

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    In another thread a bloke put one in his 2016 ktm no problem..
    #78
  19. roookie1

    roookie1 Been here awhile

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  20. SR1

    SR1 Going to America!!!!

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    a '99? I have seen several posts about post 2000 640s but not a pre 2000.
    #80