Adventurer 2+2 EFI instability issues?

[chrisjrockwell]

Hi all. New to the forums. Looking for your expertise. I recently purchased a new Yamaha Adventurer 2+2 with the QuietTech EFI and independent suspension. It's a nice unit EXCEPT it is very unstable when driving. The cart will spontaneously turn left and right with no steering input from me. We're talking significant turn (as if you were giving it 10:00 - 2:00 steering input). It's downright dangerous to drive. It seems to be more severe with weight (4 passengers vs one for example). I've had the service tech look at it and adjust the toe angle that was out. That actually made it worse. It's almost as if something is disconnected in the suspension. Any thoughts on this? Has anyone else experienced this issue? It's basically an unusable unit at this point.

[sho305]

If its a turning problem then very likely it is toe, or something is loose but you took it back they should have caught anything obvious. If you go down the road it should drive straight, turn like a car does, it should not dart or anything. They will lean in corners all the 'independent suspension' carts do but they ride better that way. That is a larger problem when lifted, usually stiffer shocks and/or springs on the rear help that. So differentiate lean from darting.

The toe has to be right on for road running, I set mine nearly straight. I find toe in will make it dart and be too sensitive, toe out will make it wander and be sluggish to turning, have poor response to input. I actually loosened my tie rods and drove down the road at 25-30mph and kept adjusting them until I was between the above and it calmly drove like it should. Then I locked them down. You have to be careful to keep the wheel straight, you turn both to move wheel, do small adjustments. You can measure it and should see the front of the tire inward just a little for proper toe. If it is then turn the tierods just a little like 1/4-1/2 turn to pull the rear of tires inward for less toe and see what difference it makes....I would guess it has too much toe but just a guess. It does not take much movement to change things at 25-30mph. Also check that steering has no play, the arms do not move, nothing is loose holding the wheels. If you do this yourself you may have to sit near the center of the cart, with one person the driver tire will steer and the passenger one has less weight it will not do much. If the toe is way off you can drive down road and hold wheel, move yourself side to side it will make the cart turn left and right....if the toe is off enough. The tire you are sitting over will steer, you can tell what way it is off.

Also check your tire pressure, I run 8 in front and 12-15 in rear ...15 for hauling wood and stuff. My cart has little weight on the front but lot on the rear that is why. Soft tires can make a cart act strange. Mind you I have 4 ply rated atv tires they are stiff to start with. At that pressure they do not roll at all hardly.

[Godfather]

Originally Posted by chrisjrockwell

Hi all. New to the forums. Looking for your expertise. I recently purchased a new Yamaha Adventurer 2+2 with the QuietTech EFI and independent suspension. It's a nice unit EXCEPT it is very unstable when driving. The cart will spontaneously turn left and right with no steering input from me. We're talking significant turn (as if you were giving it 10:00 - 2:00 steering input). It's downright dangerous to drive. It seems to be more severe with weight (4 passengers vs one for example). I've had the service tech look at it and adjust the toe angle that was out. That actually made it worse. It's almost as if something is disconnected in the suspension. Any thoughts on this? Has anyone else experienced this issue? It's basically an unusable unit at this point.

Have you tried what sho305 suggested, what did you do and did it help? I get a little wandering with my PTV