From Honda Trail Bike Wiki
The following are possible causes for this symptom.
[edit] Electrical
[edit] No Spark
Remove one of the spark plugs and end earth the base of the plug against a metal casing. Turn the bike over on the starter, obseve the plug, and watch for a spark. If there is no spark, try a new plug.
[edit] Mechanical
[edit] No Compression
Remove a spark plug from each cylinder, and either use a compression gague to check the compression, or place you finger over the spark plug hole, and feel for pressure whilst turning the bike over. Lack of compression could be caused by damaged piston, piston rings, valve clearances, broken timing gear.
[edit] Fuel System
[edit] No Fuel
Ensure the fuel tap is on, loosen the carb drain screws, if no fuel flows out, suspect a jammed flat or blockage in the supply.
[edit] Fuel Pump
The common weak spot in Africa Twin design, is the electric fuel pump. These have been known to fail even on relatively low mileage bikes. The problem is usually that the contacts have welded together inside the pump. A simple temporary fix, is th firmly tap the fuel pump to dislodge the welded contacts. If this fixes it, it's time to upgrade to the Facet Fuel Pump
[edit] Blocked Breather
Fuel supply may be affected if the breather is blocked. You can determine this by opening the filler cap. If this improves matters, check the breather hose for blockages.
