Thanks for your reply Jim.
How/where do I find out more info about the two updates you mention and determine if they have been done.
Appreciate you help.
Some of the early model FSE400 engines had an exhaust cam with a faulty decompression pin, which didn't reduce the compression enough for the starter to rotate fast enough for the bike to start. Mine, as it came from the factory, had to also be kicked over as I pushed the start button.
If it starts easily and well with the electric starter, the exhaust cam should be fine. The first FSE400 I set up for a customer was great. So great, in fact, that I got another for my self.
Mine was a problem. So much so that I finally carried it to the importer 750 miles away and had them supply me with an updated exhaust cam and reset my throttle position sensor. (It took me less than 20 minutes to change the exhaust cam and them only five minutes to reset the TPS.)
The starter gear upgrade consists of replacing the '02 intermediate starter gear with one which had some "give" in it's assembly, in case the engine backfired during the starting process. This protected the starter clutch assembly.
The new gear gave a better ratio to help the electric starter, and was made a little differently.
The easiest way to tell, if possible, would be to ask the previous owner(s). Other than that, a visual inspection would let you know, if you can get a photo of the part.
(I don't know how descriptive the drawing of the part is in the parts book, and I just found out that the GasGas web site doesn't have any parts books available for your engine. The link I gave you turned out to be for an owners' manual.)
I will try to locate an engine shop manual download for you, and also a download of parts book while i am looking. It may be a while, since most of my downloaded manuals were on a now defunct computer. (I saved the hard drives.)
I also have the part numbers for the starter gear upgrade pieces on a scan somewhere that i will try to locate for you.
It if starts and runs well, you are probably good already.
The Magnetti Marelli fuel injection and engine management system can be diagnosed by a Triumph, Moto Guzzi, or Harley dealer. (from what I've been told.) The cpu for the system is a P15 (if my memory serves me correctly.)
The only other issue I had with the bike, long term, was the starter. Being down low and in the front, it was subject to a lot of splash and an occasional submerging. I took mine apart and cleaned and greased the brushes; and replaced the rubber plug with a plug I made of "Quick Steel" (now sold as J&B Weld). Also, it is a Yamaha spec starter that has had the stud for the positive electric wire relocated. (that is the reason for the rubber plug.) This location will let the stud/bolt rotate when disconnecting/reconnecting the hot wire to the starter. Don't let it rotate, as it can break the wire inside the starter. (I restrained the bolt as I backed off the nut when disconnecting or reconnecting the wire.)
This was updated when they moved the starter for 2005.
The starter body uses a square configured o-ring, instead of a normal round bodied o-ring, for sealing the housing connection. I got spares from Stockers Starters in West Virginia.
That's pretty much all I think I know about the bike, right now.
After these upgrades, my '02 FSE400 was a fun and fast bike.
Good Luck, and Good Riding!
Jim
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