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Main Area => General GS500 Discussion => Topic started by: applecrew on December 10, 2014, 06:32:43 PM

Title: Speedometer drive gear question
Post by: applecrew on December 10, 2014, 06:32:43 PM
On my '07, the speedometer drive gear failed at about 60,000 miles - so I bought a used one off of flea bay with reportedly low miles on it - it looked pretty clean when I put it on. Well, 32,000 miles later the used speedo drive gear fails.  I'm not going to sugar coat it - I ride a lot in all kinds of weather except when road conditions are too dangerous, so the speedo gear sees lots of grit and road salt from the winter. Replacements are not very expensive but since I track every mile for fuel and maintenance, it's a major hassle because I lose anywhere from 300 to 500 miles in my log before I can replace it.

Anyone ever take one of these apart and try to service it (clean and relube)? My new replacement has low miles but looks like the bike it came from wasn't well cared for. I would like to try to prevent issues with it.

Thanks!
Title: Re: Speedometer drive gear question
Post by: PantheraLeo on December 10, 2014, 06:56:09 PM
I remember my Haynes manual recommended that I give it a generous slather of grease when I was changing my fork springs, apple.



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Title: Re: Speedometer drive gear question
Post by: applecrew on December 12, 2014, 08:25:26 AM
Well, I pulled the old one apart last night to see if there was anything I could do to it to either repair it or make it last longer.  I found that there are only three easily removable pieces - a wire spring clip, a washer, and the drive plate that has two ears that engage on the wheel and two "teeth" that engage on a splined "axle" that drives the mechanism in the sealed portion of the drive. Behind that is a sealed unit that I have no interest trying to take apart because it is still functioning.

The reason the drive unit failed is because of wear to the washer and the spring clip, which "lock" the drive plate onto the splined "axle". The spring clip, washer and driveplate are basically metal to metal contact surfaces. Wear on the clip and washer increased the amount of free play to the point where the drive plate was able to walk off of the splined axle, preventing the sealed portion from being driven.

Although I do not have the resources to do so, one could possibly obtain a washer of sufficient thickness and new spring clip to restore the original tolerances to engage the drive plate again.

I think that it is possible to service this unit as follows while it is still functioning to extend its life:

I think this could go a long way in keeping this unit functioning properly. How frequently to do this? I'm thinking about every 6,000 miles when riding under extreme conditions - a lot of wet weather riding and winter riding with road salt and grit. Your mileage may vary. Good luck!

:cheers:
Title: Re: Speedometer drive gear question
Post by: bmf on December 13, 2014, 05:35:43 AM
Interesting, thanks for the information. And i thought i had overhauled every single part of the bike already :-)