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18 or 19?

Discussion in 'The Garage' started by lakeview, Aug 27, 2020.

  1. lakeview

    lakeview XS650 Guru XS650.com Supporter Top Contributor

    20200827_194358.jpg OK, I am just putting a rolling frame together and need to know whether there are 18 or 19 ball bearings in the steering stem races and is the bottom number the same as the top?
    I vaguely recall seeing a post saying the number, but darned if I can find it.
    I know about the tapered bearing conversion and have done several but not for this frame.
     
    gggGary likes this.
  2. gggGary

    gggGary I'm listening, change my mind XS650.com Supporter Top Contributor

  3. lakeview

    lakeview XS650 Guru XS650.com Supporter Top Contributor

    That is 19 for each end, thank you Gary. I did not think about looking up fiches.
     
    gggGary likes this.
  4. azman857

    azman857 '80 XS 650SG Rider XS650.com Supporter Top Contributor

    What!? No roller bearing upgrade?
     
  5. jetmechmarty

    jetmechmarty What should I put here? XS650.com Supporter Top Contributor

    It isn't necessarily an upgrade. The ball bearing steering head steers quicker. So, if that's what you want, then going back to OEM is the upgrade.
     
    Machine and lakeview like this.
  6. kshansen

    kshansen XS650 Junkie Top Contributor

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    Just for my understanding, how does the style of rolling elements change the "speed" of the steering? Not disagreeing but just looking for knowledge!
     
    GLJ likes this.
  7. kshansen

    kshansen XS650 Junkie Top Contributor

    999
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    While on the subject of ball bearing steering head. Does anyone have the spec. on the diameter of the balls in mm's?
    I know decades ago I was replacing the balls in the steering head of a RD400 I was shocked at the price they were asking for them, seem to recall something like $1.00 each. Not bad if you only needed one or two but when buying 38 it starts adding up quick!

    Especially when a quick Google search can find 4 mm balls for $6.50 for 100! Just a wild guess on size don't go by that unless confirmed by someone with one in hand!
     
  8. jetmechmarty

    jetmechmarty What should I put here? XS650.com Supporter Top Contributor

    Supposedly, the ball bearing steering head has less contact area and less friction. They also provide better steering feel and feedback. In the case of the XS650, I'm sure they're cheaper than the tapered roller bearing steering head. The R1 came out with the ball bearing steering head, back in the 90's and I don't believe that was done for economy.
    The tapered roller bearing spreads the load much better and lasts much longer. The XS1100 came out with tapered roller bearings in 1978. My guess is because the bike was so much heavier than the XS650. It also had a higher price point.
    For the record, I wore out the OEM bearings in my XS650.

    See what Andy said.
     
    Last edited: Aug 28, 2020
    madmax-im and Machine like this.
  9. jetmechmarty

    jetmechmarty What should I put here? XS650.com Supporter Top Contributor

    I just measured one at 6.3 mm.
     
  10. Machine

    Machine Race the wind Top Contributor

    All my 70's dirt bikes were equipped with ball bearing steering stem bearings. I got use to setting them as a kid. That was after learning very young how to properly set skate board wheel bearing tension. BMX bikes and road bicycles used ball bearings throughout. Took many wild rides on ball bearing equipped speed devices. :yikes:
    Ball bearings just dont scare me enough to change now on a simple XS650.
    -R
     
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  11. jetmechmarty

    jetmechmarty What should I put here? XS650.com Supporter Top Contributor

    Angus, you may be aware of this, but the races get dimples in them and then the steering feel is a detent, usually at the centered point. Replacing the races is the fix.
     
    Mailman, lakeview and gggGary like this.
  12. Machine

    Machine Race the wind Top Contributor

    Or you can actually just remove and rotate the race 1/2 the distance of the ball spacing if you are wanting to just reassemble lol..
    I have extra races and balls for "someday"
     
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  13. kshansen

    kshansen XS650 Junkie Top Contributor

    999
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    Well a quick search on Ebay finds these:
    https://www.ebay.com/p/1643443122?iid=382850226602

    That should be enough for a few XS650'd $8.66 including free shipping. Only problem might be the location!
     
  14. gggGary

    gggGary I'm listening, change my mind XS650.com Supporter Top Contributor

    Um that's 1/4"
    Ie your hardware store has them in stock.
    Bicycle shops keep lots of ball bearings on hand.
     
    madmax-im likes this.
  15. kshansen

    kshansen XS650 Junkie Top Contributor

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    Thought it was odd that Yamaha would use a non-metric size, maybe 1/4 inch is just a more common stock size?
    6.3 mm is less than .002 inch off of a 1/4 inch size.
     
    gggGary likes this.
  16. gggGary

    gggGary I'm listening, change my mind XS650.com Supporter Top Contributor

    Bike was designed in the 60's lots of SAE standards were still in common use. Kinda like this.... Yamaha doesn't make bearings, they buy from bearing manufacturers and often use existing catalog items.
     
    lakeview, jetmechmarty and Machine like this.
  17. 5twins

    5twins XS650 Guru Top Contributor

    19,996
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    Yes, that probably explains the 5/16" balls used with the clutch pushrod. The parts diagram actually lists them as 5/16" too .....

    [​IMG]
     
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  18. jetmechmarty

    jetmechmarty What should I put here? XS650.com Supporter Top Contributor

    Doh! I measured again. 0.244 in
     
    gggGary likes this.
  19. Mailman

    Mailman Hardly a Guru Top Contributor

    That is exactly what had happened on my 77D, the race had become so indented that you could let go of the handlebars when the front end was raised and it would snap back into position. It made the bike road wild and hard to handle. Changing to tapered bearings transformed the handling. Not that there is anything wrong with ball bearings when they are in new condition.
    1407201C-149C-4E50-A9A3-230D73B3547A.jpeg

    Pete, then gave me the definition of that phenomenon.
    B54A455E-AF3F-4453-9792-ED8C6BCCCD14.jpeg
     
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  20. gggGary

    gggGary I'm listening, change my mind XS650.com Supporter Top Contributor

    bearings.jpg mbearings.jpg
    Just ebay assortments. looks like those are 1/4" mebby with some wear?
     
    Mailman likes this.

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