[Slicer1989]

I recently bought a 1990 Yamaha Big Bear 4x4 350 for a good price, But it needs it's share of work. A few problems I have ran into.

I cleaned the carb, and lubed the cables.. But for some reason the ATV wants to idle high, I've cleaned all the jets, (Didn't take any out) and I've backed all the cables all the way down as far as they will do. It idles way to high, Causing me to grind gears.

Another thing, I don't know if this is a 4 wheel drive or full-time 4 wheel drive. It only has H - L - R on the lever, and the 5 speed shift lever. Which is it? It looks like there are a few cables missing? Where can I get a whole new shift assembly and cables?

Also, It may be because it idles to high but it has trouble shifting. It's really really hard to up shift / down shit (I have to keep fiddling with the shifter to get it to downshift / upshift) I know it's an auto clutch. Is there any sort of adjustment I can make to fix that? It did sit outside for 5 years, I don't know where water did / didn't get into. Can I inspect the clutch without tearing the whole engine down? How hard are they to replace?

Thankfully I managed to find a Hanyes manual for it, But it won't be here for a few weeks.

 

[Slicer1989]

Okay. I've waited 11 days to bump this. I haven't had a chance to look at it. Nor can I find a manual for a decent price. Please help!

 

[fishingstar]

sounds like you still have crap in your jets they will need to be taken out and soaked.
you need to getthe idle down to see if that helps the shifting.
it is full time 4x4

Dan

 

[Slicer1989]

Alright. Here is a new problem... After getting the carb cleaned and it back on the road... I don't seem to have first gear at all. I believe it's stuck in 2nd gear, No matter how much I push down or fiddle with the shifter, It does not want to shift into first gear or neutral. It also has difficulty up shifting too. What could be the cause of this? Clutch? I hope it's nothing major...

 

[bhill]

Did you get it to idle down? That will definitely cause shifting problems...

 

[Slicer1989]

Did you get it to idle down? That will definitely cause shifting problems...

Yes, I got the idle down. It idles stock, and the throttle does not stick. I took the side cover off and inspected the clutch mechanism.

What confuses me the most is, I adjust it one way, I lose shifting completely (The shifter goes floppy) but it still drives, I adjust it the other way, it will go back to stiff and shift, but loses drive.

Some people have claimed it is because the shift forks are bent. I thought it was the clutch, but when it's adjusted normal, I can lift the shifter and it disengages the clutch because the engine revs like it's in neutral.


It has a really hard time upshifting, I've got it to 5th gear before, but down shifting was super hard and I couldn't almost get it back into atleast 2nd gear.

Does anyone have a diagram of how the clutch assembly goes together? Like, the linkages, the springs, etc.

 

[bhill]

hmmmm, I'm not sure what to think about that Slicer but you can go to parts websites like cheapcycleparts.com and look up your application and get a parts illustration that can give you a good idea of how things go together otherwise try ebay, i have purchased several cd"s for $15 and were just like a factory service manual..

 

[Slicer1989]

Okay, I took off the side panel clutch cover thing, Looked around couldn't see anything obviously wrong. I got it back together, And I have all the gears now. Still hard to shift. I'm wondering if it's the clutch? How can I tell if the clutch is bad?