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81 GS550 won't run aftercarb rebuild

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    81 GS550 won't run aftercarb rebuild

    Hi, I have a 1981 GS550T it ran well,but on choke the rpm's revved high.
    After new intake o-rings , new boots,rebuilt petcock and carb soak and rebuild. It now is hard starting and still revs high,but won't stay running
    when taken off choke. I am stumped.please help.

    #2
    Hee Haw Howdy!

    Hi Mr. 81GS550t,

    It sounds like you still have a leaky intake system. Check the rest of the "common issues" list in your mega-welcome!

    Let it be known that on this day you are cordially and formally welcomed to the GSR Forum as a Junior Member in good standing with all the rights and privileges thereof. Further let it be known that your good standing can be improved with pictures (not you, your bike)!

    Perhaps you've already seen these, but I like to remind all the new members. In addition to the
    carb rebuild series, I recommend visiting the In The Garage section via the GSR Homepage and check out the Stator Papers. There's also a lot of great information in the Old Q&A section. I have some documentation on my little BikeCliff website to help get you familiar with doing routine maintenance tasks (note that it is 850G-specific but many tasks are common to all GS bikes). Other "user contributed" informational sites include those of Mr. bwringer, Mr. tfb and Mr. robertbarr. And if your bike uses shims for valve adjustments, send an email to Mr. Steve requesting a copy of his Excel spreadsheet that helps you keep track of clearances, shim sizes and other service work.

    These are some edited quotes from one of our dear beloved gurus,
    Mr. bwringer, with ideas on basic needs (depending on initial condition), parts, and accessories.
    ***********Quoted from Mr. bwringer************

    Every GS850 (and most other models) has (or had) a set of well-known issues that MUST be addressed before you have a solid baseline for further troubleshooting. It's a vintage bike, and it's quite common (as in, every single GS850 I have had contact with) that there are multiple problems that have crept up and slowly gotten worse over the years. It's not like a newer vehicle, where there's generally one problem at a time.

    These common issues are:

    1. Intake O-rings (install NEW OEM or Viton only - common nitrile O-rings will quickly deteriorate from heat)
    2. Intake Boots (install NEW -- these cannot be repaired)
    3. Valve clearances (more important than most people think)
    4. Carb/airbox boots
    5. Airbox sealing
    6. Air filter sealing
    7. Petcock (install a NEW one)
    8. On '79 models, install new points or Dyna electronic ignition (or at least verify that the old points are working correctly)
    9. On all models, it's fairly common to have problems with the spark plug caps. These are $3 or $4 each, and often worth replacing if you're keeping the stock coils/wires.
    10. Stock exhaust with NO leaks or holes -- good seals at the head and at the junctions underneath.
    ***********************************
    Carburetor maintenance:

    Replace the intake boot o-rings, and possibly the intake boots. Here's the procedure:

    Here's an overview of what happens with this particular problem:

    You'll also want to examine the boots between the carbs and the airbox. There's a good chance these are OK, but check them over.
    And finally, if things still aren't exactly right, you'll want to order a set of o-rings for BS carbs from the GS owner's best friend, Robert Barr:
    http://cycleorings.com
    Once you receive these rare rings of delight, then you'll want to thoroughly clean and rebuild your carburetors. Here are step-by-step instructions that make this simple:


    ***************************************
    OEM Parts/Online Fiches:

    I would definitely double and triple the recommendations to use Cycle Recycle II and Z1 Enterprises as much as possible. These guys are priceless resources. Z1 tends to have slightly better prices, CRC2 has a wider range of goodies available. If you're near Indy and can bring in an old part to match, CRC2 has a vast inventory of used parts.
    http://denniskirk.com - Put in your bike model and see what they have.
    http://oldbikebarn.com - seems to be slowly regaining a decent reputation, but it's still caveat emptor. They don't have anything you can't get elsewhere at a better price anyway.
    http://www.babbittsonline.com/ - Decent parts prices. Spendy shipping. Don't give you part numbers at all. Useful cross-reference if you obtain a part number elsewhere. Efficient service.
    http://bikebandit.com - Fastest. Middlin' prices. Uses their own parts numbering system to obfuscate price comparisons -- can be very confusing for large orders. Cheapest shipping, so total cost usually isn't too bad.
    http://flatoutmotorcycles.com - Slow. Cheapest parts prices, crazy shipping costs. Don't expect progress updates or much communication. Real Suzuki part numbers.
    http://alpha-sports.com - Exorbitant parts prices. Different type of fiche interface that's quite useful at times, especially with superceded part numbers. Real parts numbers. Shipping cost and speed unknown due to insane, unholy pricing.

    Stainless Bolts, Viton o-rings, metric taps, dies, assorted hard-to-find supplies and materials, etc:

    http://mcmaster.com - Fast, cheap shipping, good prices. No order minimum, but many items like bolts come in packs of 25 or 50. Excellent resource.
    http://motorcycleseatcovers.com - Great quality, perfect fit (on original seat foam), and available for pretty much every bike ever made. Avoid the textured vinyl -- it's perforated.
    http://newenough.com - You DO have riding gear, don't you? Great clearances, always outstanding prices and impeccable service.
    ***************End Quote**********************
    Additional parts/info links:

    GSR Forum member Mr. duaneage has great used upgraded Honda regulator/rectifiers for our bikes. Send him a PM.
    New electrical parts:
    http://stores.ebay.com/RMSTATOR or http://www.rmstator.com/
    Aftermarket Motorsport Electrics parts for motorcycles, dirtbikes, atvs, motosport vehicles manufactured and distributed by Rick's Motorsport Electrics


    For valve cover and breather cover gaskets, I recommend Real Gaskets (reusable silicon):

    Carolina Cycle
    Discount OEM Motorcycle & ATV Parts. Warehouse Direct. Since 1970.

    Ron Ayers Motorsports
    Honda Suzuki Kawasaki Yamaha OEM motorcycle atv and side by side parts with a full line of aftermarket accessories.

    MR Cycles

    Moto Grid

    Salvage/Used

    Located in Ottawa, Kansas, Oz Powersports has the products for you. Stop by today. Oz Powersports, Ottawa, KS, Motorcycle Salvage, Salvage Parts, Accessories, ATV, Jetski, Motorcycle, Parts, Tank Sports, Redcat Motors, Salvage, GOPRO cameras, GARMIN GPS systems

    If all else fails, try this:
    Discover the world of motorcycle restoration and repair at Used Motorcycle Parts Org. Our blog provides invaluable insights into finding and utilizing used motorcycle parts, DIY repair guides, and tips for restoring vintage bikes. Whether you're a seasoned mechanic or a hobbyist, we're your trusted resource for all things related to motorcycle parts and maintenance.

    Used bike buying checklists:

    http://www.clarity.net/~adam/buying-bike.html
    Lots of good info/pictures here:
    Probably the largest Suzuki motorcycle fan site in the world. Online since 2001. Thousands of pages with technical information, pictures, magazine adverts and brochure scans of most Suzuki motorbikes ever sold in different parts of the world. Thousands of bike pictures and stories posted by the readers. ALL Suzuki motorcycle models around the world have their place here!


    http://www.bikepics.com

    Basic motorcycle maintenance/repair:
    http://www.dansmc.com/mc_repaircourse.htm
    Online Clymer manuals:
    http://search.ebscohost.com/ Click on "Small Engine Repair" then "Motorcycles". User=library, password=library. Note: This link may not work if you are on a school campus.


    Thanks for joining us. Keep us informed of your progress. There's lots of good folk with good experience here.

    Thank you for your indulgence,

    BassCliff
    (The unofficial GSR greeter)

    Comment


      #3
      Originally posted by 81GS550t View Post
      Hi, I have a 1981 GS550T it ran well,but on choke the rpm's revved high.
      After new intake o-rings , new boots,rebuilt petcock and carb soak and rebuild. It now is hard starting and still revs high,but won't stay running
      when taken off choke. I am stumped.please help.
      'but on choke, the rpms revved high' !? Of course it revs high on choke - that's the purpose of the choke. Mine revs up to 3K or more on full choke. Is that why you went thru the carbs? Maybe you mean even higher than that - if so you probably had and still have some kind of intake leak.

      Comment


        #4
        Make sure your throttle stop isn't backed all the way out or in? I think it needs at least a turn or so after it makes contact with the throttle for it to idle depending on your bench sync.

        Comment

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