Speedometer 'lagging'?

[Anonymous]

Hey folks, first time on the forum.

I have a '79 GS850G that I've had for about 15 years. I've run it off and on, without really going too nuts with it. It's an amazingly forgiving bike, being able to sit for a year, then with an oil change and cleanup, runs for the few weeks I ride, then back into the garage.

I've had it into a professional in the last 12 months for a workup (new tires, brakes, fork seals, etc), but I have 2 nagging problems. One I'll detail later (THE CARBS! MY GOD THE CARBS AGAIN!), but for now...

My speedometer tends to 'lag' behind the actual setting. I could be zipping along at 50mph, and the speedo will slowly creep its way up to accurate (over about 2 minutes), then when I come to a dead stop, it'll still show 35mph.

BTW, picture of bike (just before going off to the shop for the cleanup / tuneup - it's a bit dusty, but you can see the instrumentation: )

http://www.homeport.org/~shevett/newpix/144/P1010015.JPG

The odometer -is- working (I just rode 2 miles, and watched the 1/10th mile wheel spin happily), but the speedo is just wrong.

I've heard tell that sometimes cobwebs and yuk can get up inside the speedo, and it just needs a cleanout, but I'm very nervous about tearing into my instrumentation (since it appears you need to 'peel back' the rubber covering to get at the speedo? Help?)

I'll go on about the carbs later - seems to be a popular topic

Thanks in advance!

[mrquadriga]

Perhaps this can help....

http://www.thegsresources.com/garage/gs_inside_gauges.htm

I haven't done this yet but it does come from a respected member of the forum. Welcome by the way! - Pete '80 1100L

[Anonymous]

Perhaps this can help....

http://www.thegsresources.com/garage/gs_inside_gauges.htm

Thanks, that's helpful! Before I disassemble my instruments though, I want to make sure that's what I need to do. I've read a bunch of other threads hereabouts, and folks seem to think the gauge just needs oiling inside, so I'm willing to do it, long as someone says "Yes, the lagging meter is due to yuck inside the speedometer housing. Cut it open, clean it out, oil it, and put it back together. Go." - I'll do it

I'm guessing it's -not- the cable due to the odometer working, someone back me up on that?

How hard is it to get the speedometer out of the gauge cluster? I haven't gone too deep. I'm also digging around on ebay et al for a replacement cluster (found one with almost the exact miles I have so we'll see how that works as well.

[gspaul]

You can try lubricating your speedo cable,and the drive on the front wheel first!