Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

GS500 camshaft problem

Discussion in 'Technical and Troubleshooting Torque' started by the mole, Sep 22, 2009.

  1. Have just done a service at 21,000 km on my '06 GS500 and noticed bad wear on the cam lobes. Exhaust is worst, RH side lobe has a lot of the hard facing chipped off, LH and both intakes are starting to go. Bike has had regular oil changes every 5,000 km and has been ridden conservatively since I bought it at 3,500 km. What happened to my nice reliable bike??
    Has anyone else had this happen?
    Can the cams be repaired or am I up for new ones?
    Any advice would be welcome, thanks.
    (Will try and post some pics later.)

  2. Unless this model has an inherent problem, I find it extremely unusual that you'd have cam lobes wearing.
    Am assuming the engine is untouched from its standard form.
    Are you using the correct oil?
    Do you rev the bike much on initial start?
    Do you allow the engine to warm before heading off?
    How's your oil pressure? Does the light go out fairly quickly.. or ever come on whilst idling?
    Premature cam wear could be the result of any of the above not being as it should.
  3. Yes, I'm using the correct oil, warming up, oil pressure is good. I've been riding/working on bikes for 35 years and the early onset of this wear has got me puzzled too. My riding is mostly open road at 100-110 kph, rarely use more than 6,000 rpm except when overtaking, never over 9-10 krpm.
    Bike is stock except for 17t front sprocket (up from 16) and top box.
    I'm guessing its a manufacturing fault, nothing else is showing undue wear, oil consumption is negligible between changes.
    Is anyone aware of other cases like this?
  4. It may have a manufacturing fault as you've indicated.
    I'd replace with new items. It wouldn't hurt to have your oil sent off for analysis.
    They may find anything from oil breakdown to contaminants that may have contributed to this. At least you'll then have an idea as to WHY this happened.
  5. I'd be looking at two area, either the the hard facing on the cam wasn't done properly or one of the oil feed galleries is partially blocked.

    You may have to run the bike with the rocker cover off to prove it (that's if you can). If you can prove an oil gallery was blocked, due to a poorly punched gasket for example, then I'd be approaching Suzuki, even if it's outside warrantee. I don't like your chances, but it's worth a try. Go direct, not through a dealer.

    You can get the standard cams either reground, or re-welded, then reground. New cams are not going to be cheap.
  6. Got the cams off now and there is also wear/scoring on the alloy bearing journals, mostly on the caps.
  7. Sounds to me like a lack of lubrication.
    If Oil press is fine, check Oil feeds for restrictions.
    ( as iblast suggested )
  8. Thanks for the replies.
    Update: I removed the cams and took them to a bike shop, the guy said he'd happily take $300 and have them resurfaced but he didn't think it was worth doing and I should just run them as they are and check them each time I do the valve clearances. I'm the kind of person who likes everything to be 100%, but I guess its a lesson that it isn't always so, and that's OK.
    I'll keep a close eye on them.