Join Date: Sep 2004
Location: Medford, County of Jackson, Oregon, USA
Model: None at present
Hi mjohnson, GL1500SE is right about a rat's nest of hose. There are lots of them and it's a complicated arrangement. When they are all hooked up right the engine is an amazing symphony, but screw it up and the music isn't going to be sweet.
Just because it's aging doesn't meant the hoses are rotten. Inspecting them without removing any is a good first job. Using an unlit propane torch or WD40 sprayed around the hoses can locate leaks (I prefer propane 'cause it doesn't leave a mess). There indeed as our fellow member down under mentioned many other causes of your problem. If I remember right there was a recall on some of the early 1500s with driveability problems like you mention. A search on the forum should find some info on that for you. Or maybe some of the guys can remember better than I the details. If you do decide to replace hoses, do it one at a time so you can't mix them up. Many of them can be replaced with bulk hose, a few need to be molded due to short radius bends. In a pinch you can often insert a spring inside a hose to hold the bend open but original molded hoses are better.
Before you get too deep in the job, put in some new spark plugs, check the ignition timing, fuel flow from the pump, fuel and air filter conditions and all the maintenance items that can also cause problems. There are a lot of electrical connection to the relays and solenoids that control the carburetors. These carbs are electrically controlled to a large part so check all the wiring and connections. It's important that the sensors on these engine are working so you ought to do the tests on them too. My philosophy is to do the easy, cheap stuff first. You gotta have a service manual to get to first base on this bike, it's sophisticated, complex, and difficult to work on if you don't understand what's going on.
None at present
Past 'Wings: GL1100, GL1200, GL1500, GL1800
Current BMW C650GT