Author Topic: BMW R100 Airhead  (Read 34853 times)

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Offline Roach Carver

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Re: BMW R100 Airhead
« Reply #100 on: April 12, 2016, 11:18:39 AM »
looks perfect!

Online RAFster122s

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Re: BMW R100 Airhead
« Reply #101 on: April 12, 2016, 10:37:32 PM »
Guess that it sounds like you married this one for a while with all the time, sweat, and money. The graphite looks sweet.

I bet you are excited to have it together and working well.

Good luck!  I look forward to the photos.
David
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Offline Scott S

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Re: BMW R100 Airhead
« Reply #102 on: April 13, 2016, 04:41:27 AM »
 I look forward to being able to actually ride it on the street!
 Hopefully, the master cylinder gets here today. I only need about an hour or two to get it back together....and another set of hands. It's very hard to set up that weirdo throttle cam by yourself, or bleed the brakes. And the old paint job had scratches at the rear of the tank where the seat rubbed on it when being taken on/off, so I'll definitely need help getting the seat on.
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Offline calj737

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Re: BMW R100 Airhead
« Reply #103 on: April 13, 2016, 05:51:31 AM »
Bike looks fantastic, Scott! Use a bit of painters tape on the tank when installing the seat, and you'll be fine.  :D Throttle cables are rather tricky on these bikes  >:(
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Scott S

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Re: BMW R100 Airhead
« Reply #104 on: April 13, 2016, 06:14:32 AM »
 Yeah, the throttle cable isn't bad at all with two sets of hands. It's hard to grease the cam and hold the mark where it's supposed to be AND install the cover.
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Offline Scott S

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Re: BMW R100 Airhead
« Reply #105 on: April 17, 2016, 03:58:30 AM »
Almost seven months to the day later, she's done (I think....I hope...)

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Offline Scott S

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Re: BMW R100 Airhead
« Reply #106 on: April 17, 2016, 04:02:14 AM »







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Offline calj737

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Re: BMW R100 Airhead
« Reply #107 on: April 17, 2016, 04:06:01 AM »
Still ready to dump it!?!? If so, I'll be right down with my riding gear on  ;D

She looks really beautiful, Scott!
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

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Re: BMW R100 Airhead
« Reply #108 on: April 17, 2016, 07:48:19 PM »
Yes, it would be a fun bike to ride. Don't know if I would be able to afford Scott's price on the rides.
It looks great!  Did you intend to maintain the ability to have the saddlebags on the bike if you wanted to go touring/trip on the bike?
Those are nice saddlebags.

Oh...didn't notice the pannier frames on the bike with new paint. This Nook just doesn't work great for many images. I think it is time to root it and load a real Android OS on it, not the B&N hack.
« Last Edit: April 17, 2016, 07:51:42 PM by RAF122S »
David- back in the desert SW!

Offline Terry in Australia

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Re: BMW R100 Airhead
« Reply #109 on: April 18, 2016, 12:24:57 AM »
Nice! As much as I'd never own another pushrod boxer after being spoilt by the power and smoothness of my R1100GS, that is a beautiful bike. good work! ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

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Offline Roach Carver

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Re: BMW R100 Airhead
« Reply #110 on: April 18, 2016, 06:32:03 AM »
Fantastic transformation. That will make a great road bike. I am jealous.

Offline simon#42

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Re: BMW R100 Airhead
« Reply #111 on: April 18, 2016, 10:07:03 AM »
nice work mate .

Offline Stev-o

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Re: BMW R100 Airhead
« Reply #112 on: April 18, 2016, 08:39:00 PM »
Looks like a totally different bike...so much better! Great job.
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Offline Scott S

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Re: BMW R100 Airhead
« Reply #113 on: April 19, 2016, 03:11:17 AM »
 Thanks, guys! I got in about 70 miles on it yesterday.
 It's different, that's for sure. With the weight down low and the narrow K75 bars, I didn't feel like it was much of a handler, but the chicken strips on the tires tell a different story. I wouldn't say it does anything exceptionally well, but it does just about everything. Goes, stops, handles, rides pretty nice, etc.
 Still getting used to that progressive throttle cam deal. And the shaft drive. And riding a big twin vs. a smooth, small bore four.
 There might be a bit of an unbalance on the front wheel or something. I can feel.....something....not a wobble or even a vibration, really. Heck, it may just be "new bike" syndrome for all I know.
 So far, so good, though. Pulls pretty hard when I roll into it, too.  8)
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Offline calj737

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Re: BMW R100 Airhead
« Reply #114 on: April 19, 2016, 04:47:36 AM »
Probably experiencing that big twin pushrod motor, Scott. Wind it up (safely of course) on a long stretch and see how it feels under sustained throttle. Even better, point yourself north of 85, and ride it on up to my place. I'll give you a lift home in the car  ;)
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Scott S

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Re: BMW R100 Airhead
« Reply #115 on: April 19, 2016, 04:58:10 AM »
Probably experiencing that big twin pushrod motor, Scott. Wind it up (safely of course) on a long stretch and see how it feels under sustained throttle.

 That's kinda what I thought, too. Pistons going left and right, drive shaft going up and down, big twin rumble, etc. It's just a whole new experience for me.
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Offline calj737

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Re: BMW R100 Airhead
« Reply #116 on: April 19, 2016, 06:44:27 AM »
The other thing to realize is the cylinders aren't flat opposed; they're offset front to rear from each other just a smidge. Makes for some rotating lash. But as you become accustomed to them, they get better and better as do-all bikes.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Scott S

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Re: BMW R100 Airhead
« Reply #117 on: April 19, 2016, 09:00:12 AM »
Another 70 or so miles in this morning. I dig it. I do believe I have a balance issue on the front wheel, though; it seems to come in right around 45 MPH. It's OK above that and rock solid at 90.  8)
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Offline Scott S

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Re: BMW R100 Airhead
« Reply #118 on: April 21, 2016, 11:07:12 AM »
** '84 R100RS with dual plug heads, stock Bing carbs, 38mm exhaust, K&N filter in stock air box. Smog plumbing has been removed. **

 I've got about 225 miles on the R100 since I finished it. It runs great, got 44.2 MPG on the first fill up, no smoke, pinging, noises, popping, snapping, etc.
 It's a bit cold natured at first, but does great when warm and idles an ~11-1200 RPM.

 I cleaned the carbs, replaced the needles and emulsion tubes. If I remember correctly the main and slow jets are stock. The new needles were set at the 2nd position from the top...about 47mm when measured. Float heights set. Entire fuel system cleaned or replaced: hoses, tank cleaned and lined, new petcocks, new internal and external filters.

I didn't do a proper plug chop, but I did decide to just pull the plugs and look at them today. I'm having a heckuva time getting good pics with my phone. They all look to be just on the verge of being too lean to me. They all have some tan on the electrode and on the porcelain. One of them was maybe a tad grey vs. tan (I think it was the LH side bottom plug).
 Will the plugs burn cleaner with dual plug heads? Should I maybe raise the needle or go up on the main jet slightly?
 ** These pics were taken after a ~75 mile round trip at interstate speeds; average of 70-72 MPH. Then an approximate 5 mile ride to my house**

 


 This one's a little blurry, but it shows the color a little more true....the very light tan. There is color on the electrode and at least half of the porcelain.

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Offline simon#42

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Re: BMW R100 Airhead
« Reply #119 on: April 21, 2016, 12:18:18 PM »
that isn't telling you much scott , it only takes a second for the colour to change never mind 5 miles .
you don't know how it is on the main jet . best do a proper chop to be sure

Offline calj737

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Re: BMW R100 Airhead
« Reply #120 on: April 21, 2016, 01:23:26 PM »
Stock they are set up lean. Dual plugs do create a more lean condition. But as you know, and Simon states, proper plug chops required.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline simon#42

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Re: BMW R100 Airhead
« Reply #121 on: April 22, 2016, 12:00:37 AM »
having spent what seems like years on the dyno with my bmw  i found that twin plugging does as cal said make the mixture leaner .
however as the revs rise the effect is not as noticeable and at high revs there seems to be no difference to a single plug set up .

Offline Scott S

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Re: BMW R100 Airhead
« Reply #122 on: April 22, 2016, 03:59:42 AM »
 I'm hearing the same thing over on the Airheads forum and Facebook group. I'm just gonna keep riding it and enjoying it.
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Offline Scott S

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Re: BMW R100 Airhead
« Reply #123 on: May 05, 2016, 11:08:26 AM »

 
 There might be a bit of an unbalance on the front wheel or something. I can feel.....something....not a wobble or even a vibration, really. Heck, it may just be "new bike" syndrome for all I know.
 

 Turns out that the front tire wasn't fully seated in the bead. I don't know what it was that made me look at it, but there's a tiny little ridge that runs around the circumference of the tire. I noticed that on one side it was behind the lip of the rim.
 Took it by the shop today and he seated/unseated it and sprayed it with WD40 and aired it up to about 80 PSI a couple of times and it eventually oozed out and seated. No big POP or anything, just finally took a seat.
 Runs smooth as butter at all speeds now!
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Offline Scott S

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Re: BMW R100 Airhead
« Reply #124 on: May 05, 2016, 11:55:35 AM »
 Also, my boot heel was touching the muffler on the LH side (and only certain boots). I found a pair of these heat sheilds on eBay for $15.98 shipped. The hose clamps were WAY too big, but I had some that worked.
 No more melted shoes on the exhaust.


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