Can't get the seat to stay on

[HappySpottedCow]

How does the locking mechanism work? I have a 1980 model that has the latches in place on the frame. On the seat are two prongs that slide into the latches on the frame, but they do not catch, or lock. It seems that there should be some sort of hook or latch on one of the prongs to lock the seat down. I have been looking for a good picture of the underside of a seat to see what is missing.

Once I get this figured out then I can work on recovering the seat.

 

[Ironhead]

are you referring to the two hinges on the left side? does your seat have a single hook on the right?

welcome to the forum.

 

[arfstrom]

seems your missing the hook bar, and the spring. My wifes pop'd off a week or so ago, I just replaced the spring, and apparently the plastic seat form allows enough contortion so that the 2 angle brackets can flex just enough to allow the hook bar to slide out. and then the spring disappears too. If I think of tomorrow, I will take a photo, and put it in there
Parts 9 and 10.
http://www.powersportsplus.com/parts/search/Yamaha/Motorcycle/1980/XS400SG/SEAT/parts.html

 

[sly409]

interesting, so the 80 model's locking mechanism is on both sides? I have a 79 and its just on one side. When I first got my 79 the seat wouldnt lock into place either. I found out it was not the latch but the locking mechanism itself(the part connected to the frame). I disassembled it and found that the spring somehow dislodged itself and was sitting the wrong way. It wasnt putting any tension against the lock. So I straightening out the spring and resat it, resassembled every and voila! it locked perfectly. Try it out and see if it helps. Just make sure you remember how all the parts go and try not to lose the little pieces that might try to pop out once you unscrew the locking mechanism. Good luck!

 

[arfstrom]

My wife had this bike since 96, said she enjoyed that the lock mech wasnt working, cause she didn't have to unlock the lock, just to change the battery out, which she did daily till she stop driving the bike up to 2002/03. Then in 2010 to 2012, I have stepped in and fixed the charging system, and no longer need to get in and out of there. Like Sly said, it was just one thing bent, I was able to bend it back into shape with out removing anything.

Sly, the lock is only on one side, but they used a double hook bar, there is only one hook lock spot.

 

[HappySpottedCow]

Thanks for the diagram. I see that the seat is missing parts 9 and 10. Anyone have any of those parts they want to sell?

I want to get the seat locked down before working on the seat. I was going to cut the seat down to make it flat and then have it recovered. I found a site that actually has the a seat like that, minus the seat pan.

Thanks for the information everyone.