Trooperlife 1 Posted July 12, 2022 Recently purchased a 1986 TRX 350. Replaced the starter and had a horrible sound coming from what I believed to be the starter reduction gears. It appears the reduction gears were rubbing the crankcase cover looking at the metal dust and markings left behind. Also noticed a tooth missing from one of the gears. I opened the cover to find the stator was ruined (probably from the missing tooth bouncing around), and the magneto had a bad groove in it (see photo). I am going to remove the flywheel to see if the one-way bearing is ok. It seems to be spinning fine. If I knock down the edge of the magneto so no metal is sticking up, can this magneto be used with a new stator? 1 Share this post Link to post Share on other sites
Goober 1,555 Posted July 12, 2022 Whataya think @shadetree or @jeepwm69 i don’t think you can fix this flywheel without getting it out of balance. Can a machine shop repair it? Share this post Link to post Share on other sites
jeepwm69 7,751 Posted July 12, 2022 3 hours ago, Goober said: Whataya think @shadetree or @jeepwm69 i don’t think you can fix this flywheel without getting it out of balance. Can a machine shop repair it? I wouldn't risk it. I'd buy a used on on ebay. Engine parts for these old 350's are pretty cheap as long as you don't need a head.. 1 Share this post Link to post Share on other sites
shadetree 5,977 Posted July 12, 2022 flywheel is toast, you will need another flywheel and stator from a 1986 trx350 fourtrax only !!!!. no other flywheel and stator will work from any later 350 models. DO NOT GET TRICKED INTO SOME DUMMY TELLING YOU ALL MODELS ARE THE SAME FROM 1986 TO 1989 ??!!..the 1986 trx350 fourtrax is a ONE YEAR ONLY MODEL FOR PARTS WHEN IT COMES TO THE ELECTRONICS !!!. Share this post Link to post Share on other sites
shadetree 5,977 Posted July 12, 2022 20 hours ago, Trooperlife said: Recently purchased a 1986 TRX 350. Replaced the starter and had a horrible sound coming from what I believed to be the starter reduction gears. It appears the reduction gears were rubbing the crankcase cover looking at the metal dust and markings left behind. Also noticed a tooth missing from one of the gears. I opened the cover to find the stator was ruined (probably from the missing tooth bouncing around), and the magneto had a bad groove in it (see photo). I am going to remove the flywheel to see if the one-way bearing is ok. It seems to be spinning fine. If I knock down the edge of the magneto so no metal is sticking up, can this magneto be used with a new stator? the grinding sound you were hearing from the starter to engine case ?, i can tell you right now..its because of the gasket on the starter reduction cover !!. Share this post Link to post Share on other sites
Trooperlife 1 Posted July 13, 2022 Great info. I will keep a lookout for the magneto, gasket, and reduction gear. Appreciate your help! Share this post Link to post Share on other sites
toodeep 1,760 Posted July 13, 2022 I have ran them before with damage like that with no issues. If possible at all I would replace it though. The 86 and 87 Fourtrax (not the D) have the same stator and flywheel. Share this post Link to post Share on other sites
Trooperlife 1 Posted July 13, 2022 Ok thanks. Shadetree stated the electronics on the 1986 are specific to that year only. I will see if I can find that year. Share this post Link to post Share on other sites
jeepwm69 7,751 Posted July 13, 2022 The 350's had three different "generations" 86-87 350A Fourtrax 87 350D Foreman 88-93 Foreman The 86-87 350A Fourtrax parts will work on your machine. They're all the same. The 87 350D is an oddball one year only machine. 88-up all the parts interchange. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted July 13, 2022 What I always thought , among other changes , is the 350A is for an AC - CDI , the 350D was a DC - CDI - the 350s were discontinued here in the USA , but were still available in Canada for few years after Share this post Link to post Share on other sites
Trooperlife 1 Posted August 3, 2022 Replaced all parts except the one way bearing as it spun fine both ways on the starter gear when off the bike. Then only spun one way when connected to the flywheel so I thought it was fine. Got it all back together and it is still making noise. Ordered a new one way bearing, and am going to have to tear it down again. Does the bearing need greased prior to installation? Share this post Link to post Share on other sites
toodeep 1,760 Posted August 4, 2022 1 hour ago, Trooperlife said: Does the bearing need greased prior to installation? No. Share this post Link to post Share on other sites
