1. Dismiss Notice
  2. Hey Facebook people... We've created a group for XS650.com members to connect. Check it out!
    Dismiss Notice

Licence plate cracking

Discussion in 'The Garage' started by bosco659, Aug 24, 2020.

  1. bosco659

    bosco659 XS650 Addict XS650.com Supporter

    After only 3-400 miles, my licence plate has cracked at the mounting holes due to vibration. Anyone have a good solution to prevent this? Maybe a reinforcement plate, mounted with all four bolt holes? FF2CDBF9-8E1C-4461-B307-56A0A582D04D.jpeg
  2. GLJ

    GLJ Never go faster than your guardian angle can fly. Top Contributor

    256 crank with lead weights. Almost 7000 smiles and no signs of a crack.
    I'm sure others will be along with better suggestions:whistle:.
  3. lakeview

    lakeview XS650 Guru XS650.com Supporter Top Contributor

    Mount a mudflap/piece of conveyor belt on licence frame and mount the plate to that.
    gggGary and GLJ like this.
  4. Machine

    Machine Race the wind Top Contributor

    Chrome license plate frames are about $6. Those with an added combination of rubber and metal washers can result in a very eye pleasing and sturdy plate mount.
    maximusrising, Mailman and GLJ like this.
  5. jetmechmarty

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

    There are many good ways to do it. I like simple. For simple, go to the hardware store and buy two rubber grommets. Take the plate in with you because I don't remember the size and it might be different than Georgia or Mississippi. Make sure the grommet fits in the plate and your standard mount bolt fits in the grommet. Mount as normal. The grommets will take up the vibration. I haven't lost a plate since I started doing this many years ago. This method works and is fully compliant with the KISS principle.
    gggGary likes this.
  6. DogBunny

    DogBunny Motorcychologist Top Contributor

    If you're set up with fiberglass, it will work. That's what I did. Lay a couple of thicknesses of glass cloth on the back, saturate with resin, wait 24 hours.
  7. 5twins

    5twins XS650 Guru Top Contributor

    I make backing plates out of aluminum plate. I put rubber sheet between the backing plate and the license plate, and 4 bolt it as you mentioned. This is the plate on my '78 and it's been holding up fine since 2005 .....


    The plate for my "new to me" '83 got the same treatment .....


    maximusrising likes this.
  8. bosco659

    bosco659 XS650 Addict XS650.com Supporter

    Thx lots of great ideas. My plate is damaged so I’ll go get a replacement and rig up a reinforcing plate and maybe add grommets too.
    MaxPete likes this.
  9. bosco659

    bosco659 XS650 Addict XS650.com Supporter

    Is that 1/4” plate?
  10. Machine

    Machine Race the wind Top Contributor

  11. 5twins

    5twins XS650 Guru Top Contributor

    No, it's more like 1/8". It's very easy to cut with a saber saw, and easy to drill.
  12. azman857

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

    [​IMG] On the upper mounting hardware, I would use bigger/fender washers to spread the load to a bigger area.
  13. bosco659

    bosco659 XS650 Addict XS650.com Supporter

    Can’t find a piece of aluminum that size. Wonder if my wife would notice if one of her cookie sheets disappeared or became shorter?
  14. MaxPete

    MaxPete Lucille, Betty, Demi & Gretel: I ask, THEY decide. XS650.com Supporter Top Contributor

    This is, oddly, a very common XS650 problem but I’m not sure why.

    Some people suggest that it’s because these bikes are prone to vibration.....but that seems a bit far-fetched to me.
    DaveO, resto, ThatXS650Guy and 2 others like this.
  15. Raymond

    Raymond XS650 rider & fettler XS650.com Supporter Top Contributor

    Being a cheapskate, I use washers cut from old inner tube with scissors. Placed between the number plate and the mounting lugs.
    Last edited: Aug 25, 2020
    MaxPete and jetmechmarty like this.
  16. kshansen

    kshansen XS650 Guru Top Contributor

    On my ride to work outfit I did like 5twins did but I had a piece of scrap 1/4 inch Plexiglas instead of the aluminum plate.

    Almost hard to believe that the 1988 Sportster with over 100,000 miles on it never had the same problem as the XS650 that seldom made over a one mile commute. Must be something to do with frequency and amplitude or the fact that nothing on the Sportster is rubber mounted.

    However the Sportster did manage to destroy a Speedometer and two tachs!
    MaxPete likes this.
  17. mikesim

    mikesim XS650 Enthusiast

    Lord help you if'n you get caught! I used my wife's turkey baster for a brake fluid flush once.....

    I'm just sayin'

    MaxPete and GLJ like this.
  18. hovel

    hovel ol' stupid

    Aluminum plate is everywhere and it is free - road signs.
    MaxPete likes this.
  19. kshansen

    kshansen XS650 Guru Top Contributor

    Yea but it is a crime and how would you feel if your removing of a sign caused an accident or someone to make a wrong turn and get lost?
    lakeview and Jim like this.
  20. XSLeo

    XSLeo XS650 Guru Top Contributor

    It's not the vibrations of the bike so much as the very thin metal the plate is made from. When mounted by just the two upper holes the plate vibrates, this flexes the plate next to the mount bolts. As with any metal if it flexes enough times it break.
    Adding a stiffer backing plate and mounting with 4 bolts stops the flexing.
    Most hardware stores sell metal in many sizes of flat, angle, rod and tube as well as flat sheets.
    1/8" thick is about right. Buy the piece, cut to match the plate, drill holes to match the holes in the plate and mount with four bolts.
    No need for grommets and rubber washers.
    MaxPete likes this.

Share This Page