Honda GB500 thread

Discussion in 'Old's Cool' started by Spurlock, Aug 27, 2016.

  1. Spurlock

    Spurlock Long timer

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    A former web site dedicated solely to the Honda GB500 is now defunct, so I thought I would test the waters and see whether there is enough interest to support a thread here dedicated to this iconic bike. The purpose will be to share information on parts sources, repair and service methods, and just the joy of riding and owning this wonderful machine.

    By way of background, the GB was a somewhat retro cafe racer styled single cylinder bike designed to resemble the British Isle of Man racers of the 1950's and 60's. This 500cc 4 valve single was imported into the US for only two years, 1989 and 1990. Sales were very slow at the time, but the bike has achieved the status of cult classic now. I am fortunate to have two, a 1989 and a 1990. GB's come up for sale a few times a year on ebay and craigslist, and are often spoken of on motorcycle forums with reverence.

    So, my hope for this thread is that it will attract GB owners and wanna-be owners who have questions, advice, stories, service tips and more. As a former Honda mechanic and current enthusiast I am prepared to give what input I can, but also look forward to learning from others. For now, here are a few pictures of my GB's. GB owners please chime in!

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    -Bill
    #1
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  2. Mobil1

    Mobil1 Long timer

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    Do you know anybody that makes pipes for these.
    #2
  3. Spurlock

    Spurlock Long timer

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    Yes, a fellow named Jack Batson sells a custom exhaust system:


    -Bill
    #3
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  4. JPCollinsworth

    JPCollinsworth Adventurer

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    image.jpeg I'm in Spurlock! I've followed all of your postings here and on the now defunct Mightly GB 500 site. I have an '89 that I've restored condition original except for the smog pump.

    This picture was taken right after I got it 2 years ago.

    I saw the first one here in the flea market and just had to have one.
    #4
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  5. Spurlock

    Spurlock Long timer

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    Hey that's great, thanks for checking in! How many miles are on your GB, and have you gone back to the stock muffler?

    I sure wish there was some way to access the postings on the old GB500 site, there was lots of good info there.

    -Bill
    #5
  6. JPCollinsworth

    JPCollinsworth Adventurer

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    You're fortunate to have two fine specimens. Mine just turned over 10,000 this spring. While I still run the Supertrapp muffler, I picked another stock exhaust that looks like new. I bought it from a guy in Connecticut who also had the correct bar-end weights which I had looked for for over a year.

    Mechanically, all I've done is rejet the carburetor as I bought the bike in Colorado. I found it on Craigslist being sold on consignment by a dealer. Coincidentally, I later found out it belonged to a guy on the GB500 forum who bought it from someone in New York.

    Yes, there was a lot of good information on that site - much of which you contributed. Hopefully some others are on this site and will get wind of this thread.
    #6
  7. Spurlock

    Spurlock Long timer

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    Thanks. And for entertainment value, here is some background on the Supertrapp muffler: Back in the 1970's there was this guy Paul Moller who had a machine shop across the street from the Honda shop where I wrenched in Davis, CA. He and his team were working on developing a flying car, and apparently still are. The "flying saucer" as it was known around town used multiple gas engines to drive shrouded fans, and one offshoot of that project was the SuperTrapp muffler which was needed to silence the multiple exhausts with minimal loss of power. We would look out the window of the Honda shop and occasionally see Paul or one of his machinists cruising down the street on a bicycle with a gas engine/fan powered backpack with early supertrapp muffler, as they tested both the fan and the muffler. Paul was also a motorcycle enthusiast, so the synergy of the Honda shop and flying saucer lab led to the new muffler design being spun off as a power sports muffler/spark arrestor. You heard it here first!

    [​IMG]
    #7
  8. Spurlock

    Spurlock Long timer

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    Sounds like your GB is barely broken in! I bought my '89 from the second owner with about 15K miles two years ago and am now approaching 25K. The engine has never been apart except for new clutch discs, and runs like a clock. My 1990 model was an ebay purchase with 10, 775 miles indicated but based upon the wear I'd estimate it had more like 30-40K. That engine I rebuilt and am storing the bike as a spare. I'll post the engine rebuild details here at some point.

    Yes, hopefully other GB enthusiasts will come around. Let's keep chiming in and try to kick start this thread.

    Thanks,

    -Bill
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  9. Jon

    Jon Adventurer

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    I have actually been on the hunt for a decent GB locally for a few years and haven't turned anything up except for one that was priced above what Paul Smart Sport classic Ducatis are fetching so I had to pass. I am eager to follow though as I hope to have one some day.
    #9
  10. Spurlock

    Spurlock Long timer

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    Good luck with your hunt Jon. I always watch them on ebay and it seems lately the prices have softened a bit. Some sellers seem to have reserves north of $6-7K and the bidding only gets to around $5,500 or so. This one in California looks like fair market price to me with a buy-it-now of $5,900 and as of this minute has a bit over 4 hours to go. Go for it!!
    http://www.ebay.com/itm/Honda-GB500...ceaa5a8&pid=100022&rk=2&rkt=3&sd=172316615513
    -Bill
    #10
  11. Jon

    Jon Adventurer

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    .

    If it was within a few hundred miles from and I didn't have another bike in my sights right now I would be all over that one.

    It seems like most pricing has corrected a bit on the "hard to find" models that were recently fetching outrageous prices just a few years ago. There was a Kaw W650 listed for $12k locally about a year ago.

    Carry on with the GB discussions and keep me drooling over your bikes!
    #11
  12. Spurlock

    Spurlock Long timer

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    OK, here is this evening's GB eye candy. Going for a ride tomorrow, not sure where yet, but bike is prepped and ready to go.

    [​IMG]

    [​IMG]

    Blondie can tell I'll be gone tomorrow and is looking worried.

    [​IMG]

    -Bill
    #12
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  13. MacMcMacmac

    MacMcMacmac Struttin' n frettin'

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    One of these, an SRX-6, a W650/800, a T120 Bonneville and a Sportster Roadster with the orange/black paint job, and I'd have all my retro/thumper/Sportster bases covered.
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  14. Hammerfist7

    Hammerfist7 ADVreader Blows

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    [​IMG]
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  15. jethrocephus

    jethrocephus Keepin' the party goin' since 1958

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    I'm in.

    [​IMG]

    Will try a better picture later, bought off advrider........ Well sorted w/ suspension upgrades and brake lines, lower foot pegs or else it'd be parked a lot more.
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  16. Spurlock

    Spurlock Long timer

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    Welcome. Tell us about your bike - how many miles on it, and did you do the suspension upgrades and if so what are they? Looks like you have a Jack Batson exhaust there.

    I'm only 145 lbs. w/gear and my front forks seem to work fine. But I recently upgraded to Ikon shocks. Pricey but they made a very noticeable improvement in cornering. They have externally adjustable dampening.

    -Bill
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  17. ZCarFan2

    ZCarFan2 Been here awhile

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    I remember seeing a leftover one in the dealership in '91. At 18 I simply did not have the cash to get that or even the then-new Nighthawk 250. I still have the brochure though! :)

    I do have an FT500 now so I suppose I got the consolation prize albeit 23 years later.
    #17
  18. Mudclod

    Mudclod Mojo Moto

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    Bought my 89 when it was one year old with 1700 miles for 2200.00! It has about 10K now. Never plan to sell but man they're popular now. One on CL in Austin for 8900.00![​IMG]


    Sent from my iPhone using Tapatalk
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  19. Spurlock

    Spurlock Long timer

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    Nice find mudclod, it's great to be an almost-original owner.

    -Bill
    #19
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  20. Spurlock

    Spurlock Long timer

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    My 1990 GB is missing the tool tray. I keep looking on ebay but they never seem to show up, so if anyone has an extra or knows of one (unlikely I know) . . .
    [​IMG]

    EDIT: No longer needed.


    -Bill
    #20