Well gang, after a two and a half year hiatus (two young kids, life, etc!), I will be returning to ride this spring when the snow melts this spring!
I bought my '07 640 (third owner) in 2009 with about 7,000 kms on the odometer and only rode for 3,000 kms over two riding seasons. Since 2010, my bike has been stored and over the past two weeks, I had some work (well) done to it by my friend, Pieter, as well as starting to go through it myself.
Due to some ongoing wiring gremlins - headlights sometimes working, sometimes not (stock running lights with an aftermarket HID kit installed by the PO - no markings / brand / documentation which contributed to my frustration!), I looked for loose connections and then split wires (perhaps grounding on the frame), but after a fruitless search (I am not much of an electrician!), I decided to just replace some circuits altogether. Enter my friend, Pieter, a motorcycle / remote control aircraft enthusiast (auto mechanic by trade) who specializes in electrical.
After his initial appraisal, he decided it would be more time efficient and more useful to me in the future to rewire much of the electrical (using vehicle grade wire) onto separate circuits (as well as building custom, waterproof fuse boxes) such that any issues can be easily identified and solved in the field. Now all my lights are on separate circuits (stock running, HID low and HID high). He also reorganized the rats nest of wiring under the shroud... not that there was much room with the aftermarket horn and additional HID ballasts!
While he was at it, he mounted a trick airline fuse into the cockpit panel (another quick change fuse on a separate circuit for my accessories), hard wired leads for a phone and a GPS, as well as rebuilding my aux port (the power plug-in would come loose on bumpy ground such that anything plugged into it would only receive a sporadic power supply.)
In the future, I might see if Pieter can isolate the 'key on' circuit to further separate the lights and the battery such that it doesn't waste energy on the lights; taking away boost for the starter (an issue as read on this forum). If so, I will have to add on on/off switch for the lights as this will override the 'instant/always on' for the lights...
Finally, Pieter rebuilt and re-machined my crash bars to properly fit to allow for full radius turning; mounted by a previous owner, they contacted the forks slightly at full lock either way... not good! I had to remove them once I figured it out.
For my part, I welded a cracked subframe that was hidden by the right side panel (PO over-packing the bags?) and have started reading all the posts on this thread / other specific KTM 640 threads to try to learn of any other potential issues / areas to address. Thanks for the prior info about drilling a hole in the swingarm to release water buildup... any photos / description of exactly where you drilled?
Q: Does anything jump out regarding potential / actual 2007 640 issues that need to be addressed? Anything not included in the standard KTM owners manual checklist "MUST DO's" that a guy should be aware of?
Q: Any specific brand / model highly recommended as a replacement battery to the stock Yuasa YTZ10F MF?
I truly appreciate the contributions on here... looking forward to learning more from you inmates in the future and contributing when I can.