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Discussion Starter #1 (Edited)
I just bought a 2009 bonnie SE from a private party with 12k miles and I noticed 2 problems while on the freeway.

1) The speedometer reading is wildly off. It would say 70mph when I'm going ~55mph. Also, the tires are new and 500 miles in but I can't see why that would affect the readings so much.

2) Noise (sounds like front brake screeching) whenever I downshifted - freaked me out at first thinking my front brake was going to throw me off the bike.

After some searches, it seems that perhaps the speedo cable is the culprit.

Questions:

1) What's the most efficient (easiest) way to lube speedo cable for an ignorant novice?

I've read about people disconnecting from the top or the bottom or both. Without doing both, I can't understand how you'd be able to lube the whole cable.

2) What lube do you guys recommend? I have Du Pont Teflon chain lube, and I'm not sure if that's ok to use or not...

Thanks All!
 

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It's really easy to pull the speedo cable from either end. My preferred method is to pull it from the bottom at the wheel. Just one screw and it's off and the cable slides out. I cleaned it with some solvent and a rag, then used some 321 light oil on a rag to lube it up again. It just slides right back up the guide into the speedo and line up the spline at the hub. Tighten the screw and you're done.
 

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Discussion Starter #3 (Edited)
Ok it's too dark outside for me to check, but my curiosity is killing me:

so when i guide the inner cable up the sheath, how will i know for sure if it reconnects to the speedometer? i just have to ride it i suppose? and thank you
 

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Ok it's too dark outside for me to check, but my curiosity is killing me:

so when i guide the inner cable up the sheath, how will i know for sure if it reconnects to the speedometer? i just have to ride it i suppose? and thank you
You'll find that until it connects properly with the speedo head the cable appears not to fit fully into its sheath.

Push it up as far as it'll go and twiddle it with your fingers while pushing until you feel it engage. At that point it'll "fill up" the sheath completely.
 

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Hello

Normal procedure is not to lube the top six inches of cable (stops it migrating into the speedo head) and consider using light grease instead of oil.

Regards

Barry
 

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Discussion Starter #10
Does anyone know if a bad speedo cable can also cause screeching noises that sound like a tire locking up on the front side? I felt pretty certain that the sound was in the front, but it'd make more sense for it to be in the back.
 

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1) The speedometer reading is wildly off. It would say 70mph when I'm going ~55mph. Also, the tires are new and 500 miles in but I can't see why that would affect the readings so much.
The procedures described by the previous posters will take care of your "screeching" speedo cable; unfortunately there is nothing you can do about the (in)accuracy. They all read 10 - 15% high. It keeps your brain sharp having to do mathematical calculations while riding!
 

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Discussion Starter #14 (Edited)
The procedures described by the previous posters will take care of your "screeching" speedo cable; unfortunately there is nothing you can do about the (in)accuracy. They all read 10 - 15% high. It keeps your brain sharp having to do mathematical calculations while riding!
10-15% is acceptable to me... but the optimistc 55<->70mph disparity is way beyond that. I could be wrong. I'm going to try to find someone's car to help me compare in a more scientific way later. Thanks and I look forward to fixing this screeching problem.

I'm going to disconnect the cable from the bottom, pull the cable out, WD40 to clean the cable, lube with white lithium grease (minus the top 6 inches), and then try to guide it back up to the speedo by hand.
 

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My speedometer usually reads about 5 mph high. lately it has started "jumping" around 60 mph or so up to 80. I will try to lube it this weekend, and see if that helps.
cliff
 

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If you have trouble getting the top of the cable to engage, clamp the bottom gently in the chuck of a portable drill and spin it slowly. It'll engage in no time.
 

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Discussion Starter #18
Just an update.

I did as I described and what y'all recommended. The screech is gone! The speedometer is still off, but it looks like its off a good 10mph... even when I go 20mph, it'll say 30. I can deal with the math I suppose.

I also got the cable to engage very easily... almost too easy.

Only problem was that I screwed the cable in too hard and the plastic clamp snapped - stupid me.

Anyone know where I can find the part online? I tried to search for it but failed.
 

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Only problem was that I screwed the cable in too hard and the plastic clamp snapped - stupid me.
It happens all too often. We should have remembered to warn you, sorry.

It's not available as a separate part. Some members have glued it sucessfully with an epoxy adhesive like JB Weld and reinforced with a cable tie.
 

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Ouch, man. =( That's rough. Assuming it's the same part as is on the 2010 (US) Scrambler (I'm pretty sure it is) I have one that is spare from my box-o-parts, if you need. I'm running my electrical pickup speedo, these days, so I don't need it.
 
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