skarpenz

The frame WILL fit the old style seat as I have laid it on the frame. But I have no hardware (as my donor XS400 had no seat) to try and mount it. Thats why I'd like some pics of a XS360 and XS400 (old) with the seat up so I can take a look and see also where the rear fender mounts on the older ones.

I understand the logic of your idea but I'm working with what I have. Ideally I would have just bought an XS360 but the bike and all the parts have cost me $120 so far (complete XS400 and the XS360 parts included).

Still working on my long time project. Finally got a XS360 seat and tank and the tank I can make work on the XS400 frame but the seat is another matter, can someone post some pics of their XS360 frames again? I need a pic under the seat this time. Also, is the rear fender and tail light the same between both models? In case no one knows, I'm using a late 70's XS400 special frame and engine and putting XS360 pieces on it to make it a little more sporty (also the same as the regular XS400, its just easier to call it a XS360 conversion since they basically all looked alike).

I found this old Yamaha mini dirt bike thing in town and picked it up for a few dollars because I thought it was neat. Can anyone tell me anything about it? Its 2 stroke and doesn't run yet but it shouldn't take much.

I just realized that cylindrical peg is the tank mounting point. That sucks because mine is WAY different. Looks like I'll have to do some fabbing on this frame after all.

Oh no I measured from where you are talking about. I mean the rear reference point in the first pic. That upward pointing tube on the flat brace. Look in the pics I posted, that thing sticks out at a rearward angle instead of straight up like yours.

All my measurements jive with what you've shown me. All but one. That upward protruding hollow peg on the flat sheet metal cross brace that you used for a reference point. That brace on my bike is further back and the peg sweeps back at a ~45* angle. Is this going to be a big deal? My bike had nothing on the top of it when I got it so I'm not 100% sure what purpose that brace serves in my tank/seat dilemma. Thanks again for the help. Any input is welcome right now. I'd really like to get the frame to the powder coat shop tomorrow but if I need to cut and weld something then I will hold off.

Thanks very much.

Okay, so I have all the solid engine mounts from this bike since I dismantled it myself (no rubber bushings). The only thing I am concerned with is the fitting of the long skinny seat and the square tank.

Any idea what sort of measurements and reference points? Thanks for clearing up the year and whatnot.

Hey guys, I have been buying up and restoring/selling vintage Jap bikes for a little bit now and I need to know exactly what I'm working with here. I picked up a 1979 Yamaha XS400 roller (complete frame/engine/wheels/brakes) without a tank or seat/seat pan. I'm thinking its a XS400 Special which is sort of a bummer because I want to build up a plain XS400 for a sportier bike. I can't complain though, I scored the whole thing for $60. I disassembled the bike before ID'ing it exactly but here is a picture of the bare frame. My main concern here is this: If I source the seat pan and tank from a regular XS400 will I have to heavily modify the frame to fit those pieces? I do NOT like the look of the Special, it just isn't my style. If anyone could give some insight on this it would be much appreciated. Hell, if I could just see a detailed picture of an XS400 with the seat and tank off I could make the comparison myself. Also, if anyone could list the specific differences between XS400's and the Specials then that would be great too. There does not seem to be much in the way of literature on these bikes. Thanks for any help guys! Pics: Some pics of my other projects; CB550fourK ($65) and GS1100EZ (Dad's):