My 1st Airhead R75/6

Discussion in 'Airheads' started by lake_harley, Jun 9, 2012.

  1. disston

    disston ShadeTreeExpert

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    The Aluminum turn signals are nicer than the plastic ones. Sounds like they were cut, or the stalks were cut, to make room for the fairing. Too bad they would have easily unbolted. Most did it that way and then bent the stalks out of the way of the fairing. Look under the headlight ears you might see the rest of the stalks. You probably will need new stalks to mount them. The wires to the signals may still be in the headlight shell or it should be easy to make new wires if needed. The stalks are pretty cheap on Ebay used but watch out for the longer stalks, they go on S bikes. The longer ones go for ten times more than the shorter ones you need. I actually think those stalks are also still available new at an Airhead friendly dealer.

    You have the /5 carbs on your /6. This is a common happenstance. It's so common that there may be more of the R75/6es with the /5 carb than the /6 carb. The carbs you have will work fine. When you see stuff in a manual though and it involves talk about the R75/6 carbs they may not have the right info for your bike. Capice? I'm going to give you the info for both the /6 and the /5 carb. There's actually more to it but this info will be enough for now. Some may think they want to jet those carbs according to proper /6 jetting. I don't think that would be a good idea. Use them as they were made the day they were put on that bike by BMW. If you want to get more fancy some years from now there are better carbs to have and they aren't even Bings. But right now just use what ya got.

    R75/5... carb# 64/32/9&10... main jet 135... needle jet 2.70... jet needle 241... idle jet 45... idle mix setting 0.75...

    R75/6...carb#64/32/13&14... main jet 145... needle jet 2.66... jet needle 241... idle jet 50... idle mix setting 0.50...

    I know about the highly recommended spline lube. I now think it's over rated. Do it if you want the experience, it's a wonderful way to waste time and bond with your machine, or there are specific shifting issues that you think might be helped by the spline lube. After you get the bike running, #1, then we'll talk about shifting issues. If you really want to do this it's OK just put it off a little while. Maybe till winter. Instead of starting with a big project that you might not need just be ready for something, or anything, that you actually do need.

    Anyway, you now have the bike home and it's almost ready to start? What to do? Change all the fluids, is a good idea. At least the engine oil and filter, the gear oil in the trans, swing arm and final drive. You can leave the surprise of the front end for later. Clean the gas tank and petcocks, clean the float bowls on the carbs, replace the fuel lines if they look even a bit old.

    If the bike came with a battery charge it up and see if it holds a charge and you think you might live. Other wise buy a new battery.

    Fresh gas, a clean airfilter (new one if needed), set the enrichners to full on and give a little twist to the throttle then crank away. You should have this thing running in a day at most I think.

    Don't forget to wear a helmet.
    #21
  2. crazydrummerdude

    crazydrummerdude Wacky Bongo Boy

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    Although I think it's immediate importance is over-emphasized, a spline lube would only take a n00b an evening.
    #22
  3. disston

    disston ShadeTreeExpert

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    BTW, add to your carb info; for either of these carbs, the /5 or the /6, the clip position is # 3.
    #23
  4. lake_harley

    lake_harley Been here awhile

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    disston...what a wealth of info and encouragement. Thanks! I'll certainly do and check the items you listed.

    I couldn't believe how perfect the inside of the tank looked. At least a rusted tank is one thing I don't have to worry about or deal with. I'm hoping the carbs are in equally good condition. The petcocks move freely, with a definite "detent" in each position. I guess that's a good sign.

    Makes sense to possibly put off the spline lube if shifting is OK. Can't imagine anything will get trashed in a few miles. I'm not going to ride this bike across the country any time soon. Just want to service, maintain and hopefully improve the bike over time. No total "restoration" for me. My goal is a good running bike with all of it's naturally aged character.

    Battery is nearly new so that's one expense that shouldn't pop up. I'll get a battery tender on it ASAP. I have mine loaned out at the moment so it's time to call it in.

    Thanks again!

    crazydrummerdude...I think early in this thread you mentioned something about a possible meet-up. I may PM you sometime if I'm going to be in the STL area to see if we could work that out. Planning a Sat/Sun/Mon ride with possibly two brother's-in-law, and one of their buddies....next weekend, I think. Leaving from the Wentzville area is the current plan. I have no idea where we might be going, but sometime before, during or after the ride maybe?

    Lynn
    #24
  5. disston

    disston ShadeTreeExpert

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    lh,

    The info I had to give came from the Bing Carburetor Manual which is really cheap. It may even be in a newer edition, mine is 2001 dated. This cost $11 from the Bing people. Their web site, where you can order the manual is;

    http://bingcarburetor.com/

    Sometimes people order parts from the Bing company direct. It's a funny part of the business but the carb parts are cheaper from a dealer or any of the other parts suppliers. That is except for a couple of things that only Bing stocks. These include the float needle seat which is sometimes needed.

    They also sell an Alcohol Independent Float set up. Don't get it. Some will say it works. Most have not had any benefit and ended up taking them off.
    #25
  6. crazydrummerdude

    crazydrummerdude Wacky Bongo Boy

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    Sounds good. Or, I could go to your place and lend a hand on the bike..
    #26
  7. lake_harley

    lake_harley Been here awhile

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    crazydrummerdude.....Help on the bike sounds great! By the questions and photo's below you'll see how little I currently know about airheads. I do have a manual ordered, so that should help.

    There had been a number of questions asked, and some I had too, to help identify various things about the bike. Here goes....

    This is the centerstand that's on the bike. It feels really sketchy since it barely takes any pressure off of the suspension when it's fully deployed. Maybe it's bent and/or going over center too far. It mounts to what I'm pretty sure are the stock center stand mounts on the frame.


    [​IMG]

    This is the wonky sidestand that is welded onto the left footrest bracket. I can't imagine it's any aftermarket item, more just a homegrown, crude abomination. I'm sure it will be surgically removed via a cut off wheel and carefull dressing the bracket to look unmolested once again.
    [​IMG]

    Next, we have the right and left handlebar controls, since there was some discussion whether they were '74 or '75 units, regardless of what year the bike is listed on the title. The dimmer switch on the left control is currently non-functional (stuck, and I don't want to force/break it). Can these units be disassembled relatively simply to clean them up?
    [​IMG]
    [​IMG]

    Last, for this installment anyway, is a fitting on the right, front side of the oil pan. There's not a wire or anything nearby that would suggest it was a sending unit, but to me it looks like a broken off sending unit. I havent done a lot of looking at other similar age bikes, but haven't noticed the same thing on others. Am I missing something obvious (probably :becca)?
    [​IMG]


    Thanks again, for now.... I did fiddle with the bike a little bit last evening. I took off the frame mount for the Windjammer fairing that had been on the bike, so that required seat and tank removal. That allowed me to a least wipe off some of the grunge and spider webs from the things under the tank. Also noticed for the first time that the left side of the tank is caved in slightly. No creases, so I'll take it to a friend of mine who owns a body shop. He had taken some similar dents out of tanks in the past, so I'll see of he can bring it back to normal without ruining the paint, since I'd like to keep the bike original.

    Lynn
    #27
  8. DoktorT

    DoktorT BigBrowedNeandereer

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    You are very much at the split between 74 and 75 model year. I wouldn't be surprized at all if it was a mix of parts on hand the day it was assembled. Could have the last of the 74 rotors or the drilled ones of 75. Could be either switch gear and wiring harness.

    Post a pix of the details and a bunch of heads hear can identify what you got.

    74/75 differences. Front axle, 14mm 74 or 17mm 75 so front wheel hubs/bearings are different. Solid rotors/drilled rotors. Switch gear/harness. Pattern on seat cover different. Alloy turn signal housings 74, plastic 75. First year of 5sp tranny was 74 and is an albatross. 75 was improved. 76 was resolved of all issues with the earlier production.

    The number at the oil fill boss is the VIN. That's why you can confirm original engine by comparing to the same no. on the steering head. The engine number is different and found left front side on the oil pan flange on the crankcase.

    Now I see the photos. Switch gear is 75 and have never seen them on any factory 74. 75 switchgear and harness means the factory says it's 75. Front axle diameter should confirm it.

    You have an aftermarket deep oil pan.

    The center stand is the common Reynolds Ride Off stand. Do take the time to remove and inspect the mounting lugs, clean the threads and hardware. Install the bolts with blue lock tite thread locker. Lube the bushings with grease. Too danged many of those bolts just fall out. Best to keep an eye on those every 30 or 50 operations to verify they remain tight.
    #28
  9. disston

    disston ShadeTreeExpert

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    The Reynolds ride off stand will use the stock BMW bushings and bolts but uses different springs. Might find springs that work at hardware store but I don't know. I'm looking myself.

    The side stand is not stock. The bracket for the original may be broken or missing. You might want to keep that one till you find out what you need to get something that looks and works better. Brown side stands look better. They are not stock but most riders don't like the OEM side stand anyway.

    I just looked again at photo and notice you also have the stock sidestand.

    Switches can be taken apart if you are a minute detail guy. Needs more natural talent than directions. And if you don't need a new one now you might need a new one before you're done but you might as well give it a shot. I've been missing the tiny detent balls in my switches for over ten years because I took mine apart. Half a brain and you should be OK.

    That is an after market temp sender to read the temperature of the engine oil. If it doesn't leak you can just leave it alone.
    #29
  10. chasbmw

    chasbmw Long timer

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    The sidestand looks like an early Surefoot. BMW used to close for holidays in August. This meant that the bikes produced in september were the first of the new model year production. So your bike is a 75, but incorporating some 74 items such as the earlier aluminium indicators. I think that Motobins sell stainless steel front and rear indicator stalks, not cheap but better than OEM new.

    Good luck with the bike
    #30
  11. lake_harley

    lake_harley Been here awhile

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    Had a little bit of time today and decided to see why the center stand leavs the bike so wobbly (center stand pictured a few posts back...#27 I think). Took it off and cleaned it and the bolts and bushings up to take a look. Threads in the frame lugs looked to be decent as did the bolts. Bushings and the hole in the stand wasn't terribly wallowed out nor did the stops seem really worn, especially on the stand itself (but then I'm new to the airhead). Thought the problem was that one of the bolts was really loose when I took it out. Things were a little less wobbly when I put it all back together (red LocTite on the threads) but still not even enough "lift" to take weight off the suspension. I can still actually tip the bike right and left with the stand deployed. Not too confidence inspiring. Both sides of the stand are 'ground off", I'm assuming from use, but that would probably have taken less than 1/4" of height from the diameter of the bottom tube. It seems to me the stand is just too short. Is there any particular reason that these stands are used to replace the stockers? A stock center stand will actually lift one wheel (front?) off the ground about 1" or so, won't they? I have good fabrication equipment and could build up the stop on the stand so it didn't lean quite as much, actually making it taller by standing more upright, but also thought about finding a stock /6 stand. Thoughts?

    Thanks

    Lynn
    #31
  12. Bill Harris

    Bill Harris Confirmed Curmudgeon

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    That POS is a Reynold's Ride-Off Stand. It's not designed to hold the bike up too far off the ground. Some people like them, most people dislike them.

    Google "Reynold's Ride-Off Stand" for the full scoop.
    #32
  13. lake_harley

    lake_harley Been here awhile

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    Bill....I Googled per your instruction and yeah, there's a lot of opinion out there, pro and con, on the Reynolds stand. I may look at just slightly building up the base of the stand, to firmly plant the stand, which should keep the bike from rocking. I think as little as an extra 1/8" thickness (height) per side might do it.

    Thanks

    Lynn
    #33
  14. Bill Harris

    Bill Harris Confirmed Curmudgeon

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    That is essentially what I did with mine-- by the mid-'80's I wore the "tippy-toes" off the stock centerstand so I added a cross-piece made of galvanized plumbing pipe that hasn't worn through yet. And it has the advantage of providing a nice, wide and stable "foot" that doesn't sink into dirt or asphalt. I think that the inspiration was an accessory centerstand called the "BigFoot".

    Pics attached:

    [​IMG]

    [​IMG]

    [​IMG]
    #34
  15. lake_harley

    lake_harley Been here awhile

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    Bill....thanks for those photos. I'll have to compare the angle of "lean" of the deployed stand on your bike compared to mine. That should help me decide whether the frame lugs/stops are worn, letting the stand lean excessively, and by that, making it effectively "shorter". The stop portion of the Reynolds stand on my bike looks fine, but the frame lugs are 37 years old, so there's a chance for some wear:lol3

    Lynn
    #35
  16. Bill Harris

    Bill Harris Confirmed Curmudgeon

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    :y0!

    I can help there, too-- mine angled to far forward from wear and tear, so I brazed a couple of bits onto the centerstand stop tabs. The deployed angle of the stand measures 75 deg from the horizontal, tho I'd suggest 80 deg. When it angles too far forward you really have to wrestle it off the centerstand-- it needs to be just slightly over-center.

    I'd weld the first tab stop, make it a bit too thick and grind/adjust it to "perfect", then measure and add the other one. If you can support the bike so that the return-spring-less stand can swing below it will help-- I cluelessly did mine trial-and-error over several trials, but I was just an energetic kid back then... :gerg

    [​IMG]

    [​IMG]

    BTW, my "BMW Photo Album" is at http://s142.photobucket.com/albums/r91/wilga_photo/BMW R60/ and contains images for stuff I've posted as well as images that "might be useful".

    Eventually I'm going to swap the bike stuff over to our SmugMug here...
    #36
  17. lake_harley

    lake_harley Been here awhile

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    Thanks again, Bill....I noticed your location as "backwoods Alabama", so I guess there might be a similar "make it work" mentality with me, being more or less "backwoods Missouri":D I like to "make it work and use it up". I did notice a significant difference in your stand vs. the Reynolds, in that the spring runs forward on your modified stocker, while my Reynolds has long springs that run rearward and wrap around a frame crossmember and hook back to the "uncoiled" stem of the spring.

    It seems the amount of pleasure I get from a bike is proportional to the sweat equity I have in it, and inversely proportional to the amount of money I have invested. Of my bikes right now, my favorite is my ~$600.00 '83 Gold Wing that was brought back from near death after it survived a tornado and the following 2 1/2 years of neglect. Since it's resurection, I've ridden it 12,000+ miles and recently did a SaddleSore 1000 on it. My wife is really comfy on it,too, so that makes me even happier! I think the /6 is going to give the 'Wing a run for satisfaction and gratification once I get it running well and back on the road once again.

    Thanks for the centerstand info and pics!

    Lynn
    #37
  18. Hawk Medicine

    Hawk Medicine Coyote's Brother

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    Welcome to the asylum!

    If you havnt been bitten by the bug yet, you will be and then you'll really love owning your Airhead. They can easily become an addiction!:lol3

    I knew immedietly from the manufacturing date, that you have a 'transitional bike' and believe me, those things can be "fun". All these little detail differences here and there. After a while, it's just part of the charm!

    If I'm not mistaken, that side stand is a "Shufefoot" and they are generally considered to be /2 items. If yours is welded to your footpeg, don't cut it off, just replace the peg. The surefoots are really good stands. Theyre utilaterian, they can stand up to the weight of a loaded bike and they won't let the bike "roll off the stand" but then again, I'm one of the several guys who like the stock stands just fine. At least you won't have to worry about draging them during spirited riding!

    That "Reynolds Ride Off" centerstand? I wouldnt be so quick to cut it up or throw it away. First, look for the part number and a I might be able to tell you whether it's the correct one for your bike. They came in several lengths, depending on the bike model and yours may well not be "correct". Theyre also designed such that you should be able to roll the bike on and off the stand w/o much effort. Thats a good thing for you old guys. but if you keep it, put a length of 2x4 in the bags, just in case you get a flat and need to get your tire(s) up in the air. Me? I like the RRO stands but don't currently own one and I also don't have a sidestand on my bike right now either. Just the stocker. Go figure...:huh

    If you remove that center stand, clean it up and put it on the shelf. Those things are getting scarce and you might want it sooner or later.

    The other side of the coin is that the stock /6 centerstands are expensive new from BMW and good used ones are a little scarce. I'd look for a used one and be prepared to have a little welding done if the botton is badly worn. Most of us have been there and done that.

    Hot tip! When you take that switch apart, do it within a plastic bag please. Don't ask, just do it!:wink:

    If you can get together with CDD, I'd suggest that you do so. Hes become a dyed in the wool Airhead and hes a pretty good guy to boot. (Or at least he was when I met him!) He'll probably be able to save you a lot of head scratching and cursing during this early period of ownership. Especailly if your bike isnt running yet. Most of us around here whould have that bike running in an evening and once you have a runner, everything else falls into place.

    Drain the tank, clean if necessary, check the floats, change the oil, add fresh fuel, charge the battery and it'l probably start right up. Everything else is either restoration or maintenance. :D

    Oh... And buy at least one shop manual. I'd suggest the Haynes to begin with.

    Good luck!
    #38
  19. supershaft

    supershaft because I can

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    I just stack shaped plates up on the curved part of the stand and weld them on and then grind them a bit if need be to reform the original curve. I weld the top of the stand there too. It will last a lot longer than brazing.

    Man that stand in it's retracted position would kill me! I modify my center stand stops to allow my stands to retract further into the frame by quite a bit and I still get grind marks all over both sides of my center stands in both my LS and my R100. I drag them HARD without those road hooks protruding out like that. That's scary to me. Be careful! You might have to avoid a car some day and that stand could launch you right into it!
    #39
  20. lake_harley

    lake_harley Been here awhile

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    I've been doing a little tinkering here and there on my 75/6, mostly when I just couldn't resist doing something toward progress on it. After weeks of that I managed to drain and flush the gas tank, replace the fuel lines, change the oil&filter, trans oil, driveshaft oil, final drive oil, put a couple squirts of Marvel Mystery Oil in each cylinder for good measure, and flushed and bled the front brakes (which was a waste of time and brake fluid since I still want to replace the line). I then set about un-f***ing the wiring. The bike had a Vetter fairing on it and the wiring plug pigtail was still hooked into the system. That was removed from the headlight bucket and the original headlight was re-installed.

    Eventually, with the continued piddling I verified spark & compression. A push of the starter buttun produced nothing. Switch checked OK. Problem was traced to a bad start relay, for which a replacement was ordered. It arrived today. I installed it and put the tank back on, added a little bit of gas, and after removing the float bowls to let a bit of gas flush through the needle and seat, pushed the magic button and without any choke (enrichener?) it fired up after just a couple seconds. In moments I had a nice smoke cloud in the garage as all of the oily smudges that I didn't get off the exhaust pipes burned off. It idled nicely after just a few seconds. I shut it off, rechecked the oil level and topped it off since it had filled the filter.

    After giving the bike one last mental and visual checkover I started it up again, clicked it into 1st and rode it up to show to my neighbor who has been somewhat amused following my 6 year "stream of motorcycles". To and from my neighbor might be 400 yards total, but it felt good to be on my first airhead moving on it's own! I even clicked it into 2nd on the way back, so at least two gears work:lol3.

    The only odd thing I noticed, after it ran for a while and was idling, I heard somewhat of a rattle or light knocking noise. When I've seen and heard airheads in the past I admit I never really listened to them so I am unsure if the noise should be a concern of if it's normal. I don't think it's a rod, or merely valve noise, since it seems further back on the engine transmission assembly. There were no chunks in the engine oil that I noticed, and no metal shavings on the magnetic transmission drain plug. Clutch rattle, possibly? (It's not "Ducati loud"...I had a 748:D). I think it was with the clutch released and the transmission in neutral, but now I'm not sure.

    I also tried using all three of my hands to check the voltage at the battery with the engine running. I was having a hard time holding two multi-meter probes in place and holding the RPM up a bit, so I never did get a good reading. The battery/charge light does go out when the engine starts, so I'm hoping all is well in the charging system.

    Next up is the brake line that was mentioned before ( I have a friend who makes all manner of high pressure hydraulic lines at a good price), and then it'll be time to get front turn signals back on the bike ( have them, but they need work), get the headlight dimmer switch working or replaced, tires and it'll be ready for state inspection and licensing.

    Before I really start riding it, I intend to change all the fluids again in about 20-30 miles, just to thoroughly flush everything out.

    That's it for this update.

    Lynn
    #40