I bought a 2007 klr 650. It has no horn. i havn't been able to locate the wires for it or the original location. can some one help? Thanks

check fuses also relay switch

It should be as close to the battery as possible, but it could be inside the headlight unit, or near it.

The clutch also must be engaged there is a safety interlock on the kickstand and on the clutch handle.
Also the kill switch by the throttle (red rotating switch) must be on run it also prevents the starter from working.

The usual point of failure is the interlocks, you can unplug the connector from the interlock switches and jump them to test if they are working.
the clutch switch is by the pivot end of the clutch handle.
The kickstand switch is under a plastic cover about halfway up the frame, there is a cable like a bicycle brake or shift cable that runs from the kickstand to the switch under the cover.
I have a wiring diagram for this bike, if you still have problems let me know and we can run thru troubleshooting procedures.

EX .006-.010
IN .004-.008
Yes it uses shims to change the clearance.
Shim calculator here- http://klr650.carguy.org/shims.html

The flasher is located underneath the front of the fuel tank fust behind the horn. I hope this helps. I am looking for a wiring diagram for the 1981 Yamaha XJ 650.

in shop visit weeklyvisiters.blogspot.com

Battery Constant 12v+ Positive Wire (+): Black/Orange And Red/White
Battery Constant 12v+ Positive Wire Location: Ignition Switch Harness
Starter Positive Wire (+): Yellow
Starter Positive Wire Location: Ignition Switch Harness
Ignition Positive Wire (+): Blue (16 Gauge)
Ignition Positive Wire Location: Ignition Switch Harness
Second Ignition Positive Wire (+): Yellow/Red
Second Ignition Positive Wire Location: Ignition Switch Harness
Accessory Positive Wire (+): Blue (10 Gauge)
Accessory Positive Wire Location: Ignition Switch Harness
Second Accessory Positive Wire (+): Orange
Second Accessory Positive Wire Location: Ignition Switch Harness
Parking Light Positive Wire (+): Black/Yellow
Parking Light Positive Wire Location: At Headlight Switch
Power Door Lock Positive Wire (+): Orange/Violet
Power Door Lock Positive Wire Location: In Drivers Kick Panel, White 6-Pin
Power Door Unlock Positive Wire (+): Pink/Violet
Power Door Unlock Positive Wire Location: In Drivers Kick Panel, White 12-Pin
Door Trigger Negative Wire (-): Yellow
Door Trigger Negative Wire Location: At Headlight Switch
Domelight Supervision Wire: Use Door Trigger (Requires Relay)
Domelight Supervision Wire Location: N/A
Horn Negative Wire (-): Black/Red
Horn Negative Wire Location: At Steering Column Harness
Tachometer Wire Negative Wire (-): Gray
Tachometer Wire Negative Wire Location: At PCM, Connector 1, Pin A7. The PCM (powertrain control module) is located on the firewall next to the wiper motor.
Brake Light Positive Wire (+): White/Tan
Brake Light Positive Wire Location: At Switch Above Brake Pedal
Factory Alarm Disarm Wire (-): Black/Orange (To disarm requires a (-) negative through a 1565 ohm resistor and an extra relay to connect.)
Factory Alarm Disarm Wire Location: In Drivers Kick Panel, White 12 Pin Plug
Factory Anti-Theft System: N/A
Factory Anti-Theft System Location: N/A

Under the seat next to the battery,just jump the to large wire connectors

http://www.bigcee.com/faq/KLR650-color-wiring-diagram.jpg

try to look down by the motor mount, i ride a Factory YZF-450 thats wear mine is.