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Seat Position on my 73 R75/5

kjmcd13

New member
The seat sits a bit to the left in the back and I was wondering how to straighten it. It is good in the front and opens and closes smoothly. Can I bend the hinge a bit? Everything seems to be straight in the back except the seat. Was there different seats for this model besides a solo seat?Seat.jpg
 
Mine has done this too and in my case it's because the rear hinge has actually bent inward, not quite as bad as yours is however. Trying to rebend it may however break it off, so be prepared to weld that thing back on straight if you have to.
 
Actually, the hinge looks straight as a pin. Anybody else have this problem or have any suggestions? I guess i have no choice but to bend the hinge.
 
I would be hesitant to just start bending things. There has to be a reason that the seat is off. It has to be either the seat or the subframe. It certainly would be helpful to have another /5 next to yours for comparison. Maybe you could take some pictures from various angles and post them here. Include the seat and the subframe. Then others with a /5 could go look at theirs and/or take their own pictures.
 
Good idea Kurt.

If the seat hinge is bent, go to the trouble of taking it off of the bike before you try and "correct" the situation. You'll have more leverage to work on it and you won't be stressing the hinge pins on the subframe, or the minimal weld on the hinge itself.
 
I vote that rear hinge. Make it look exactly like the front hinge and see what happens. Be careful and support the lower part of the hinge so you're not just ripping out the screws. If you can remove the hinge, best to do it that way...in a vise.
 
I recently replaced both hinges on my seat for my /6 from dealer parts (yes, they are available). I will have a look when I get home and let you know.
 
Well, maybe not exactly like the front... It doesn't look bent at all to me. How far "off center" is your seat?

Rear
a definite "recurve" visible between the mounting plate and the beginning of the "hook".
52531236351.jpg


Front
52531230314.jpg


edit - you have a very early LWB /5 seat like mine; you can see the joint where to two seat were grafted together. You might want to lay a straight-edge along the cease on the bottom side and see if it is straight.
 
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Good catch, Lew... it's clear the shapes are a little different front and rear. It appears from his first picture, the seat is off about 1/2 to 3/4 of an inch.

What about the right side subframe...does it appear to be bent in the middle some? See my picture with the red circle...go back and look at the original.
 

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I caught that bent subframe too. I was at work and couldn't post images.

If it is, it's in the "perfect" spot to effect the seat. I think this is the culprit, not the seat. A subframe isn't too expensive to replace.

New File Manager is kinda cool too! Especially the "in line" feature.
 

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Then again few of these old bikes is perfect....
what's wrong.jpg
What's wrong with this picture of my /5 (the obvious doesn't count)?
 
The rear wheel seems a bit more to the right side. And for some reason, that I can't think of, the right carb seems to stick out farther...I know the carbs are positioned fore-aft differently with respect to each other, but I wouldn't think inboard-outboard. Could just be camera angle. :dunno
 
d'oh! hadn't noticed the right-hand carb leaning outboard ... swing arm is centered, but the rear fender is tweaked to the left by about 1cm at the back ... I finally gave up trying to figure out why. I did do a total relamination on the underside with epoxy and glass cloth, it may have taken a bit of a set to one side :dunno
 
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