The ergonomic experiment

I've never had a pivot bolt issue either, but I stay within the specified torque range when tightening them (32-58 ft/lbs). Last install took about 45 lbs to get the arm set properly, gently dropping under it's own weight.
 
I will say that my experience is 75 and earlier. My 75 race bike had so much slop in it that I could pull up on one side and push on the other and get a 1/2 inch deflection at the top of the rim t. It had ~10,000 miles on it and was 3 years old.

Factory building fixtures wear out when thousands of assemblies are built in them. Often the end of a model run is due to fixturing needing replacement $$$.
Gary you are right. I think they would of continued building them for a while longer if some major piece of tooling had not worn out. The tooling was paid for by 76-77 I would think the margins were great and the specials made them some much needed cash while they transitioned away from the two strokes.
 
:popcorn:

XSJohn was a serious advocate of slightly retarding timing and lowering compression for a smoother running engine better suited for a relaxed riding style
http://www.xs650.com/threads/tci-timing-tweak.55209/
http://www.xs650.com/threads/a-collection-of-xsjohns-mods.2426/
I retarded the SG's timing about 2° last summer. It gave me a noticeable improvement in starting.... just touch the button and it lights right off. It's also a good hedge against detonation. So that right there was worth the price of admission. Other than that though, not much change really. Had to set the idle up a little, but no noticeable change in performance or vibes.
Be curious to hear others results.
 
Yes, I think this motor runs nice with the timing retarded just a hair, set over by the right side of the idle timing "range". But, we're really not running it retarded at all. When these bikes first came out, the timing spec was more retarded. The idle "range" was 10° to 15° BTDC. Early in '71, Yamaha changed it, "updated" it to 13°-17° BTDC, supposedly to smooth out the low end and idle. So, when we reset to 12° or 13° BTDC, we're basically right in the middle of the old original spec.

LHseEFl.jpg
 
Thanks Steve,
I’m looking at your photo and I think I managed to pull off, roughly, that same position.
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Now if I only had about 60 more horsepower we’d be on a level playing field! :D
Sorry bob wanted to sneak this in here since you said I'ma sposed to be work'n on my bike!
mock up 2.jpg
 
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Thanks for those pics Bob.
I think they highlight why I'm planning on dropping my seat (and the rear frame rails dammit) to get closer to Steve's position, yet not be sitting sky high.
ps yer cheating Bob; the headers are MIA!
 
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Thanks for those pics Bob.
I think they highlight why I'm planning on dropping my seat (and the rear frame rails dammit) to get closer to Steve's position, yet not be sitting sky high.
ps yer cheating Bob; the headers are MIA!

I had also thought about reshaping the foam on my seat a little to give it a little bit of a butt bucket / pocket. Lately however, I’ve been thinking about just sectioning out part of the foam in the front half and adding in a piece of 1” memory foam. Just enough to let me sink in a little. It would retain the factory look of the seat. Kinda as described here,

http://www.sussexmotorcycles.com/elite-comfort-motorcycle-seats.html

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Pics of the highway pegs relation to the exhaust pipes coming in a few moments.
Check back here, ;)

Ok, here we go. There should be plenty of room without hitting the pipes. If I were careless I could probably touch the heel of my boot on the header. Hey, you know what’s fun? Climbing up on my bike to take photos, while I have the back wheel off the bike. I swear the things I do for you guys! :D
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Looks good Bob! Maybe put heat shields on the headers to prevent a hot-foot (or hot-leg)? The same with the 2-into-1 Delkevic style system I want put on "The Basketcase". My right foot will be over (close, but, hopefully no hot-foot) the pipes, and I might squeeze a heat shield in there if needed. Once you get to "a certain age", or start having parts replaced (like my knee), the "feet-under-ass" position starts to lose its appeal, and a more laid-back seating position is desirable. I lack the required flexibility for a lot (most!) of the current crop of sport bikes. Ego vs. Reality I suppose. :shrug:
 
A Modest Proposal (apologies to J Swift)
Bob, you clearly need a new project. It is time to find a Special ( you don't have to reinvent it). The specials were Yamaha's answer to the cruisers that were popping up like mushrooms. Start your recliner experiment with the buckhorns and bones of an 80s Special. Go from there. I will definitely follow the thread!!!!!
 
Bob, you don't look very comfortable in your new riding position. It might fit me though:rolleyes:.
I have a special seat that I have a new cover for and to lower the seating position for my 'short inseam', I will find some memory foam for it. Thanks for your post. Glad the weather's been bad here and haven't recovered it before.:thumbsup:
 
Bob, you clearly need a new project. It is time to find a Special ( you don't have to reinvent it). The specials were Yamaha's answer to the cruisers that were popping up like mushrooms. Start your recliner experiment with the buckhorns
I will gladly contribute the very nice buckhorns from the '82 I bought recently :)

XS82.5small.jpg
 
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