R80ST gets the GS Treatment

Discussion in 'Airheads' started by Airhead Wrangler, Dec 24, 2008.

  1. Airhead Wrangler

    Airhead Wrangler Long timer

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    As I understand it, increasing your compression ratio will increase your thermal efficiency (ie less waste heat per unit of kinetic energy produced), but in absolute terms it will increase the amount of waste heat produced. Any authorities out there care to dig into their mechanical engineering text books and clear this one up? Anyone up for some D&D in Blake's parents' basement?
  2. bgoodsoil

    bgoodsoil Dare to be Stupid

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    I've got Cameron's book on motorcycle performance in my "pannier of holding', gimme a sec, lemme find it.....he says more compression = more heat, in general. He recommends larger radiators on water cooled bikes to overcome that more heat so that you can run more compression. The BMW, with it's singled sided swingarm, is already defying all laws of physics. Perhaps they don't apply on our bikes.
  3. datchew

    datchew Don't buy from Brad

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    I think it's a fantastic conversion you've done. I'm interested to hear what you think of simply bumping up the fork oil weight vs installing gold valves. :ear:ear

    I have progressives and am considering the gold valve mod, but if simply changing the oil is a good enough improvement (as i'm not that hard of a rider) then I'd rather do that.


    By the way, I heard that Blake lives in his parents basement and doesn't get laid. Sounds like a vicious rumour , but i'm gonna pass it on. :lol3 (love ya Blake... ya coming to the fling?)
  4. Airhead Wrangler

    Airhead Wrangler Long timer

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    Yeah, I figured I might as well establish a baseline before I try to improve on it. Improvement on an untried suspension setup is tough to gauge. That and I was just plain sick of wrenching on my bike instead of riding it. My riding to wrenching ratio has been a little too lopsided lately.

    Yeah, I heard he still wears a retainer and cuts the crust off his sandwiches. Not sure where I heard that, but I'm pretty sure I DID hear that.
  5. Stagehand

    Stagehand Imperfectionist

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    i got the D+D reference :cry


    just for the record, I do get laid, (occasionally) and I dont live in my parents basement, but occasionally I get laid in my parents basement. Once I even got laid in the basement playing D+D, but I'm sure this is too much info. And here we were discussing gas laws a moment ago, and also for hte record I think you (Dat) should definitely try the fork oil route first.

    Also for the record, I have never seen an aircooled bike much over 10:1, and all the 12:1's I know are heavily auxcooled, so I would think the more compression would equal more heat, despite the inefficient burn of low comp.

    Looking back, i realize this adds very little, but I like this thread. :D
  6. Readymeal

    Readymeal Been here awhile

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    I did not get the D&D even though i played it. However i thought he was talking about the card game called Magic the Gathering which i never played...

    Alright i never lived in my parent's basement since they never had one, I got laid plenty times playing role playing games...well in the game :):rofl I have to confess i get laid sometimes too(not depending on me though :) ... but so far the only one giving me pleasure whenever i want has two wheels and is parked in the garage :D

    i don t know much about the high compression thingy and heat...sorry
  7. igormortis

    igormortis Cafe Reise

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    The cooler running higher compression engines may be related to tighter squish clearances between the piston and head surfaces. This leads to more efficient combustion and lower cylinder temps.

    I don't know any specifics with regard to the Airhead engines, but it makes sense and it would be worth looking into. Someone with more knowledge than me may be able to chime in with better than my rudimentary explanation .
  8. bgoodsoil

    bgoodsoil Dare to be Stupid

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    Man, when my build thread got hijacked it was with a 7 page discussion on circlip failures. You get a buncha geeks trying to pretend like they never played Dungeons & Dragons. I'd be pissed.

    Thanks for the info on getting driving lights instead of fog lights. I probably would have gotten the wrong ones.

    I went with some Hella lights rather than the PIAAs since they're ovals instead of round like yours. My Exxon tanker takes up a good bit of crash bar real estate and I'm hoping to mount them in front of it. I'll probably be wiring mine up the same way-through the high beam switch since, like you, my HID doesn't have highbeams. Do you have any more good ideas I can steal from ya?
  9. datchew

    datchew Don't buy from Brad

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    :lol3:clap I think Blake might have some competition on quotable quotes.
  10. Airhead Wrangler

    Airhead Wrangler Long timer

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    Nothing wrong with some comic relief.

    Wait, what were we talking about? Oh yeah...bikes.

    Next project got started today. Stainless steel infill panel to go on top of the headlight mount to hold the trailtech, idiot lights, and ignition switch. I figured it was about time to actually fab something from scratch instead of hacking up, filing off, bolting on, and bending other people's work. Progress has been made, but pictures were not taken. More coming later.

    Next mention of D&D gets a swift kick to the undescended nuts.
    :thwak
  11. Gorp

    Gorp Malakas

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    Airhead, been following your progess for a while, as I have an ST also. It is an '83 w/ 13k on her and a sweetie. However, as I've sold all my other bikes and been disappointed in a search for a G/S, (and the fact that no matter how clean you think your bike is, someone has a nicer one), She will now become a G/S also. One question I may have missed is where did you get the bashplate? (sump protector).
    Gorp
  12. Airhead Wrangler

    Airhead Wrangler Long timer

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    It came from an ADV inmate, ernie. You can check out all his wares at twinheadlighternie.smugmug.com then click on dakota motorsports.

    Keep in mind you'll have to change out the sump for a GS sump as the ST didn't have the threads to mount a bash plate. Good luck on your project. Don't forget to save all your ST pieces. There weren't many of these to begin with and not nearly as many now, so it'd be a shame to take a complete one and scatter it.
  13. Renner

    Renner combustophile

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  14. Airhead Wrangler

    Airhead Wrangler Long timer

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    Yup. Been there. http://www.advrider.com/forums/showpost.php?p=8021041&postcount=6

    I got around to finishing my dashboard yesterday as well as making a fatfoot for my sidestand with some of the leftover stainless. The dash convinced me of my need for a drill press. I designed the dash on a computer, printed out a scale print of it, taped it to a stainless plate and punched all my centers. I used a small bit to drill pilot holes with a hand drill, but due to the toughness of the stainless that I used the bit wandered a fair amount without me noticing and consequently the holes for the idiot lights aren't spaced evenly...at all. :cry Oh well. It's functional and that's good enough for me. The GPS got mounted, but not wired yet. The steering head bearing got adjusted as the races weren't fully seated when initially installed. Riding seems to have pushed them in a little further. I also picked up some handlebar risers at touratech on the way home yesterday and now my handguard mounts don't smack my tank before full lock. :thumb

    No pics yet - maybe tonight... if I don't blast up to the mountains for a night time shakedown run on some dirt
  15. BubbaZanetti

    BubbaZanetti for a corrector life

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    what a cool thread.


    i'm about to come into a R80ST, but i'm gunning to do more of a "cafe all rounder" type bike that is good for looking "hip" in nyc, touring and maybe a little off road.:lol3 this thread has certainly given me some ideas.:thumb
  16. Stagehand

    Stagehand Imperfectionist

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    I'm supposed to make a joke here about you needing more than a bike to look hip :evil but really, they used to say if it will play in Poughkeepsie, it will play in New York :lol3 so when you get it- tour yourself up here!
  17. Renner

    Renner combustophile

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    Airhead Wrangler: like your threads man, and I was trying to get that Gorp fellow to visit the registry.

    Your ST mods are highly inspirational... I hope to spend some quality time in the garage with my '83 this afternoon.
  18. BubbaZanetti

    BubbaZanetti for a corrector life

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    i gonna be heading up that way this weekend on my S, but to hopefully sell it, and will be riding a train home!:lol3

    cafe thing's big in bklyn though, i used to have a 84 R100 with a mild cafe job, i really miss it.
  19. Airhead Wrangler

    Airhead Wrangler Long timer

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    Well, just a couple things to cover:

    1) My super ghetto stainless dashboard complete with somewhat cockeyed idiot lights

    [​IMG]

    2) Super carcinogenic, toxic, corrosive carb cleaner and the wonders it works. Now, I was well familiar with the capabilities of aerosol carb cleaner like Clean-r-carb and others. This stuff is several orders of magnitude nastier and more effective. When I first got the bike it had sat for 20 or so years with the petcocks on. The float bowls were basically a solid block of waxy, crusty gasoline varnish. I went through at least 3-4 cans of spray carb cleaner getting them "pretty clean," but there was still plenty of persistent crud that wouldn't come off the inside of the bowl or the area above the float without scraping. That really left me wondering what was still lurking in all those tiny passageways. The bike ran and ran pretty well. Well enough that I didn't hesitate to rack up 13,000 miles on it last year. Anyway, there's a rough spot in the rev range and a a tiny bit stumbly idle which just couldn't get tuned out, so I decided to go back in and do the last 20% of the carb cleaning. This time they got the crazy death dip, new floats, new o-rings all around. The first time around about a year ago to the week I replaced the diaphragms, main jets, idle jets, needles and needle jets, so by now they're completely rebuilt. Here are some pics

    Before:
    [​IMG]

    [​IMG]

    After:
    (note that berryman's dip WILL take the white paint off your bing name plates)
    [​IMG]
    [​IMG]
    [​IMG]

    Squeaky clean and new looking. Thanks Solo for loaning me the Berryman's. Now I have my own personal EPA superfund site.

    Here's what you can use those cracked valve covers for: :lol3
    [​IMG]
  20. jedcaum

    jedcaum Lucky, Lucky Bastard

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    Yikes, dude - you gotta destroy the evidence, not take pictures of it! And use your test light for roach clips, silly - lotta waste there in your recycling :wink:.