Re: Sargent Seat High position problem and fix.
« Reply #41 on: September 27, 2012, 09:51:36 am »
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I have the seat and use it in the high position. I do not notice any difference. For me it is just right. (6"4" 33" inseam)
But there is a problem with the seat pan in the high position!
As most of you already know, the Tenere has a seat adjuster plate that allows two seat heights. When the adjuster is in the high position, it aligns 4 posts that are about 7/8” in diameter and an inch high with 4 of the 6 cushions on the seat pan that are about the same size and shape. Given the small area of the posts and cushions, they must align very closely to work right.
Problem:
The problem is that with the seat in the high position, after riding 30 minutes to an hour depending on the temperature, the left rear rubber cushion slips off of the post and drops the seat in that corner about 1”. When weight is removed from the seat it pops back up. But as soon as weight is reapplied it slips off again. If the seat is allowed to cool down. It will work correctly until it warms up.
Cause:
The Sargent seat pan is less ridged than the stock pan. This is easily observed by flexing the two pans in ones hands. The stock pan seems to have a little more robust stiffening ridges, and seems to be made of a stiffer material. At any rate the Sargent pan is just stiff enough until it gets warm. Once warm, it flexes enough to allow the cushion to slip off the post.
The Tenere has it’s radiator on the left side and a fair amount of heat is flowing down the left side of the bike. The rider can feel it but it is not to the point of being uncomfortable, at least not to me.
So what happens is the seat pan gets warm from the rider on top, the motor heat rising, and the radiator (left side). That makes the pan less stiff and at some point it flexes enough to allow the rubber cushion to slip off the post. The pan is not hot but warmer than the ambient air. My guess is 100 to 125 degrees F.
Fix:
It needs more testing but I did around 40 miles last night with this and no issues so far. It is just a short piece of 1” PCV pipe over the back left post. The length is .725”. It effectively just increases the size (surface area) of the post so the rubber cushion does not slip off. If you look close you can see a small notch in the bottom that I made to clear the small rib on the adjustment plate.
I first tried a longer section of tubing thinking it would lock the post and cushion together but the post and cushion do not line up correctly. They are about 3/16” out of alignment so the tubing cannot slide over both, and that misalignment may contribute to the slipping off problem. With this shorter section, it is at the level or just a little higher than the post.
Is anyone else seeing this issue?
I know at least one other person called Sargent about it."