Ok, so. I replaced the Stator and cintrifical clutch. I'm not sure what was the bigger problem but after tests I found both were gone. She runs great now, and the spark will jump about 30mm which is about the limit of my tester. Alot better than 2.5mm!
I took the time to also replace the coil as it was only $20 and the clutch packs since I had it all apart. Nither was worn that bad but I figured what the hell.
After it was all fixed up I put on a new exhaust and a set of new grips. LOTS OF POWER NOW! Took her on a 100km trip today up a hill thats 1870ft above sea level and changed the oil and filter again when I got home cause I figure any time you got the engine opened up it can't hurt to be carful. The filter had a lot of junk in it too.
So if anyone has the same issue, I say:
-Check Cintrifical clutch
-Check spark jump and make sure it's over 6mm.
Part costs:
-Yamaha Genuine Cintrifical clutch: $287.00 USD
-Ebay stator: $89.95 USD
-Ebay Coil: $19.95 USD
-Ebay Clutch disc set: $35.99 USD
-Scott Hurricane ATV Grips: $6.95 USD
-Slightly used Yamaha YFZ450 Exhaust (I modded it to fit the bear): $78.00 USD
-Ebay Clutch gasket: $9.99 USD
-Ebay Stator gasket: $8.99 USD
I am having the same problem with my 1995 350 Big Bear,
I am wondering if I can only change out the internals of the centrifugal clutch and not the housing or do they both need to be changed?
I'd say more than likely you can get away with just the clutch, the housing usually doesn't wear that much, but it is the cheap part. Lots of good ones on ebay for like $20
The clutch, on the other hand, is not.
Buy a new one though, don't make the mistake of getting a crappy used one.
I've read your posts and you seem quite knowledgable about some ATV's... I was needing a little help my 2001 Kodiak 400 at. I have a K&N air filter and a jet kit installed, but a firend recommended an exhaust to really increase my power? What are your insights and what brand would recommend? I don't want something noisy...or
.... "pay alot for this muffler"
Wish I could help, but I'm not really the one to ask about such things. Everything on my ATV is stock (with the exception of maybe the handgrips).
I don't usually replace anything unless it's broken, and the only add on's I have on my Bear are: Extra halogen head lamps for high beam, a halogen reverce lamp, a 12v DC outlet, winch, rear seat/cargo box, a side mirror, and a set of handwarmers.
I also replaced the clutch packs as I figured I might as well for the extra $40 seeing as how I had it apart. Changed the oil. Have 10w40 atv oil in it now.
