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Main Area => General GS500 Discussion => Topic started by: DoD#i on July 25, 2008, 06:35:24 PM

Title: Gory Pictures (sprocket cover - worn sprocket?)
Post by: DoD#i on July 25, 2008, 06:35:24 PM
Ripped into the bike before snow flew due to my cranking problem (solved, I think). Waiting on a couple of parts for sorting out fuel mess, considering a quick start on fixing the ugly paintjob. Found and fixed an improperly installed intake boot (folded up inside the carb horn, so about 1/4 of it could be seen from inside the airbox.)

Anyway, today I got out the 8mm socket (and a 10mm for the shifter) and opened up the sprocket cover. Mmm, gunk. Looks like the previous owner used grease on the chain, and had rodents (really greasy rodents) hiding under the sprocket cover (sunflower shells in the gunk).

I also think the front sprocket looks a wee bit worn - though there's not as much of a step as I expected to feel going from the shiny rim to the brown center, the tooth shape looks off. Rear (I think) looks OK. My other bikes are/were shaft-drive, so the whole (motorcycle) chain thing is new to me.

(http://gstwins.com/photogallery/albums/userpics/18510/GrottySprocket.jpg)

(http://gstwins.com/photogallery/albums/userpics/18510/normal_WornSprocket.jpg)(http://gstwins.com/photogallery/albums/userpics/18510/normal_RearSprocket.jpg)

Opinions? Nothing to worry about, swap ASAP, ?
Title: Re: Gory Pictures (sprocket cover - worn sprocket?)
Post by: nastynate6695 on July 25, 2008, 06:37:23 PM
ehh looks good for the most part  spray the chain with lube tighten her up and ride.
Title: Re: Gory Pictures (sprocket cover - worn sprocket?)
Post by: The Antibody on July 25, 2008, 07:56:48 PM
I will have to disagree there. It looks like your in need of a new chain. The sproket could be replaced as well, it looks worn. Sure you could ride as is, but it isn't in ideal shape.

  -Anti  8)
Title: Re: Gory Pictures (sprocket cover - worn sprocket?)
Post by: Trwhouse on July 25, 2008, 08:03:52 PM
Hi there,

That is way more than just a bad countershaft sprocket, bub.
You need to replace it all now, before you ride it anymore.
If you run a new chain on that countershaft sprocket, it will wear the new chain out quickly and be dangerous because that sprocket is badly worn and disfigured.
Replace both sprockets and the chain with quality new parts and you'll feel the difference.
Best wishes,
Todd
Title: Re: Gory Pictures (sprocket cover - worn sprocket?)
Post by: Ronin on July 25, 2008, 08:23:28 PM
Yep that chain is shot to hell! Spocket is right behind it.I'd check out a new back spocket also...check for oil leaks behind the sprocket and clutch rod,also the gear shifter they look fresh wet. :thumb:
Title: Re: Gory Pictures (sprocket cover - worn sprocket?)
Post by: DoD#i on July 26, 2008, 05:43:17 AM
Quote from: Trwhouse on July 25, 2008, 08:03:52 PM
If you run a new chain on that countershaft sprocket, it will wear the new chain out quickly and be dangerous because that sprocket is badly worn and disfigured.

Yeah, I know that much (bad sprocket makes bad chain - change as set) from chainsaws.
Title: Re: Gory Pictures (sprocket cover - worn sprocket?)
Post by: sledge on July 26, 2008, 08:18:12 AM
You see that Red oxide dust around the center of the sprocket? Thats a by-product of Corrosion Fretting. Similar to this... http://www.renold.com/Support/Fretting.asp . It indicates that the splines have started to wear. When you fit the new sprocket you can limit this wear by making sure the shaft and splines are cleaned and then lubricated with a heavy grease that wont fling off, or Coppaslip will do. Do this 2-3 times a year, otherwise there is a chance the splines on the shaft will carry on wearing until they fail completely........leaving you with a major headache.

More info on Corrosion fretting here.... http://www.poeton.co.uk/w1/p-solver/fretting.htm

I have seen several GS5s on the bay and in various breakers that have been written off due to failed output shaft splines, seems to be a common problem with high-milers.