ADVrider (
-   Airheads (
-   -   1978 R100S :: final tweaks? (

mspa 08-26-2012 02:28 PM

1978 R100S :: final tweaks?
Let me start off by admitting this is technically a Bitza. Short story is the frame and basic parts are a 1978 R80/7, and everything else came off a 1978 R100S with bent frame. As far as my joy of riding and ownership is concerned, it feels and looks like a R100S. For purists, it's a bitza. But I love it!

So I'm hoping to get some tips on what I consider the need for "final tweaks" for this phase of ownership. I have to say I've seen some really nice cafe versions of these bikes that for me will have to come later when I have a second bike for commuting, and this can graduate to weekend warrior. Having a bitza makes it much easier to make that change down the road.

Now for a quick background to set the stage. I got this bike from a former bike tech (Honda, BMW, H-D) who did the build work. I have to say not only does he know his stuff, he's a super nice guy that has become a friend over time as we continue talking about the bike. He has been invaluable in helping me understand my bike better, and really enjoying it!

The odometer doesn't work—as is the case with these older bikes—so our best guess at mileage is about 50k. Pretty low for a 34 year old bike. But when you examine the bike up close, it's believable. I plan on having the speedo/odometer rebuilt in the next couple of months. Until then, I keep a journal of miles driven so I can at least have a rough estimate prior to putting miles on the odometer. That will give me a baseline of sorts.

Upgrades done before I purchased are:
– Dyna III electronic ignition (with new ignition advance springs)
– Space Age Control bar backs
– Bikemaster American Superbike bars
– BMW grips
– Mac Whispertone exhaust (large spigot)
– Denfield seat (NOS)
– Bullet "S" fairing

Repairs/maintenance prior to buying:
– rebuilt top-end work included gaskets, rings, valve guides, valve springs, valves and related machine work
– dual port front master cylinder
– rebuilt rear disc brake master cylinder
– replaced clutch
– correct cables
– lube/fluids all new (BMW 20-50 oil)

Repairs/maintenance prior AFTER buying:
– Yuasa 53030 battery
– Bosch W5DC plugs (the seller media blasted the W5DC plugs I fouled trying to start with a dying older battery, like new now, as backup)

Current tires:
Metzler ME 33 Laser (front)
Bridgestone Spitfire 11R (rear)


As you can see, the bike looks great and runs like a top. I love it!! In my mind, I'm 90% there with only a few things I'd love to make decisions on: tires, bars, and grips. I'm glad I don't have to mess with rear shocks, since the new Ikon replacements are pricey. It has Koni-Holland 7610 shocks on the rear and I'm liking how they ride and ease of adjustability.

Clubman bars?
I just ordered some genuine Napoleon mirrors in chrome. I need better visibility than what I have with the stem mirrors. This means I have to do a custom install as my throttle sleeve is close ended. What complicates this decision is that I sometimes think I want clubman bars for a more comfortable ride. 90% of my riding is my highway commute to work (12.5 miles). The bullet fairing splits the air in a way that if I sit up, I get blasted with air, whereas when I ride in the position the fairing is designed for, my elbows are farther back than I like with my hands further back than I'd like. So obviously, in that position, clubman or low euro bars would be ideal. By the way, I'm curious how you guys feel about the black chrome vs. chrome Napoleon mirrors. I ordered chrome since I noticed the black ones show rock pits and they look beat up faster. Not sure if you can have those repainted? I figure any clubman bars I get will be chrome, so the mirrors would match. Otherwise, they match the trim components like turn signals.

However, I enjoy sitting upright on weekend jaunts on weekends, and I've been trying to imagine if I'd enjoy the lower bars, during my weekend rides. If I decide solely on which riding position gets more miles, I'd go with the low bar. Since clubman bars are relatively cheap, I'm thinking of buying some to try out. But only if I don't have to invest money in other parts that make it a more costly adventure. Considerations to achieve this are: fitting with the fairing on, using existing control cables and mounting on the Space Ace bar backs. Does anybody have experience in this area with specific bars that worked well, and still allowed full steering radius?

If I decide to try out some clubman bars, I'd love to leave the grips I currently have on the Superbike bars, just in case I put them back on. This would mean I'd need to find a second throttle sleeve (original?) and new set of grips. I've done quite a bit of looking around and there seems to be a large variety of "cheap" looking grips, and a few nice looking pricey grips. I'd love to get some ideas for grips that are under $50 a pair.

Tires [Update: had a shop put the new Metzler on today, in correct direction]
I've done some reading on the Metzler's and agree with the majority thought on their pros/cons . . . and as far as I can tell, the Bridgestone rear is pretty good. The only issue I had with that was a little pucker I had last Friday going through an intersection with steep upward slope and changing gears, while accelerating across the crosswalk painted stripe. How many no-no's is that?? :D

The Bridgestones are newer and logic stands to reason that I replace the front and get the most out of the rear. I'm thinking about selling the Metzler on craigs to offset buying a new front tire. Just so you know, I'm trying to keep my expenses down on this hobby to keep my wife happy. This all started as a "cheaper" way to commute to work. So I can't go too crazy now.

I think that's enough talking now and it's time to show some pictures so you can see what I'm working with. Some pictures without the fairing were taken yesterday. It's easy to take off and I wanted to see how it would change the riding experience with wind buffeting. Made a BIG difference. But I have to say, the bike is more sporty with the fairing, which seems to give the bike a contemporary clean look. Plus the fairing will keep the instrument cluster cleaner over time, and offer protection from the occasional rock that comes my way.

Houseoffubar 08-26-2012 04:49 PM

WOW, looks very clean! :wink:

Houseoffubar 08-26-2012 04:49 PM

Oh, and welcome!!!:lol3

DoktorT 08-26-2012 05:07 PM

For the instruments, do find on this Airheads site the one called Wirespokes. He will fix your instruments for a more reasonable fee than the big suppliers and has decades of experience. Just a home shop Airhead who has been helping Airheads with instrument repairs to wide acclaim.

disston 08-26-2012 06:21 PM

If the frame says it is an 800 then it's an 800 on paper. Might be advantages I think.

Looks nice. Real nice. I like those mufflers and pipes. I had some of their stuff 30 years ago and it was high quality then. I'm thinking of getting Mac again.

supershaft 08-26-2012 07:41 PM

My advise is that the front tire is on backwards. I would run fork gators to protect the tubes. I would run steel braided teflon brake lines for improved feel, better brakes, and I have seen a lot of rubber lines getting too old and failing this way or that lately. IF you use those bag mounts they crack all the time. I would gusset them and get a cross brace that goes from mount to mount behind the fender. They're brazed. Braze the gussets on. I would roll the bars back so that the bar ends aren't sticking up like bull horns. The bars are designed for the much more natural position that they put your wrists in with the bar ends turned down or at least level. Most but not all bars work best with the upright portion in line with the fork tubes. I love BMW K1 bars and they don't work that way but most do. Good luck!

sealsam 08-26-2012 07:44 PM

Looks great! Congratulations and welcome to ADV.

Your bike looks and bit familiar. Mine...

I got mine last fall and cosmetically it was pretty rough. Mine did not come with the 'S' fairing so I considered trying to find one, but instead I threw on a National Cycle windscreen. The NC screen is working out just fine and does what it needs to do, getting the blast off my chest and chin.

I had it painted by a local shop with an Audi blue which is similar to the BMW color(I'm no purist either). I had the snowflake rims powered coated which has worked out good as far as keeping them clean. Steering head bearings have been replaced which really improved the drivability tremendously!

I just had my speedo and tach refurbed by Wirespokes, that you can find here on ADV. I just posted up a thread thanking him for his work.

These airhead are just fun, fantastic machines. Mine has caused my RT to do alot of sitting this past year.

Good luck with yours, it's a beauty.

mspa 08-26-2012 08:51 PM

Thanks for the warm welcome guys! Great comments and advice in only half a day :D

disston = the frame says 80/7 "Made in West Germany", a piece of history . . .

DoktorT = thanks for the referral, I"ll contact him soon.

supershaft = you got an eye like an eagle! Is that a simple matter to flip the wheel around, or is it more involved? I figured I'll put gators on at some point, partially 'cuz I like the looks. For now, I clean them off every few days. My ride is so short each day, that they stay clean. But I always make sure there are no bug guts left on. What's the best source for proper gators? I'm not sure I completely understand what you mean by "Most but not all bars work best with the upright portion in line with the fork tubes." But I get what you're saying on my current bars. I'll adjust them and see how I like it. Thanks!

samthg = you got a nice bike there too :) I like that stock seat with grip bar around the back. I'm thinking about getting a tank bag too. I completely agree that these are terrific bikes and really fun.

mspa 08-26-2012 09:10 PM

supershaft, I'm looking at the bars and realizing I may not be able to rotate the bars down for a more level or lower position without hitting the tank at full left/right. I have about 1/8-1/4" clearance with control switches so I don't have to worry about how tight I turn. I won't hit the tank.

Now as you see in the photo below, what I mean. Actually, the wheel isn't in the full left turn position, so there is even more space. I think it may be necessary to replace the Space Ace bar backs with something more forward. I'll loosen up those four bolts on the bar backs tomorrow and see if it's possible to move to a better position and not cause any cable issues. Wouldn't think that would happen.

I'm trying to not spend any more money right now and save up. I'm tapped out after buying the Napoleon mirrors. I'm hoping I'll like the chrome mirrors and not wish I got the black. You guys have any thoughts on that?

mspa 08-26-2012 10:24 PM

Hey Samthg, do you have stock bar backs on your bike?

mspa 08-27-2012 07:49 AM

I loosened up the barback to move the handlebars and can't rotate down any more without the switches hitting the tank. I think the best solution will be to swap the barback for something that allows the bar to move forward an inch or two and now hit the fairing braces. I need to figure out if the barback comes off easy. It appears that the front bolts on the barback require removing more parts . . .

disston 08-27-2012 10:55 AM

I don't think any of the '75 vintage bikes had bar backs. They had bar mounts that raise the bars an inch or so above the top clamp. With stock bar mounts the bars will be forward a little more. But those don't look like BMW bars anyway. Hopefully you don't run into a problem of the switch gear having it's original 22 mm size hogged out to fit 7/8 inch bars. The more common size bars are the inch size. BMW's use 22 mm which is a little smaller. When people put 7/8 bars on a BMW they often hog out the bore of the switch gear. And it is difficult to then make these switches fit stock bars.

If the switches hit the tank try rotating the switches. This will also put the levers in a bit different position but there is leeway to make some adjustment at the switch.

supershaft 08-27-2012 11:07 AM

I forgot to mention the bar back. Personally, I hate them. I have test ridden tons of bikes with them. They make your bike feel like a tiller IMO. I would take them off. Find some stock handlebar mounts. I think I have some. Then you will be able to mount your bars like they should be.

Fork boots. Look up the PN# on Max's from another /6 or /7 model and order them from your local dealer. That is if they don't charge more than the price on Max's site which is retail.

I don't remember if those wheels have an direction arrow on them? The brake disc bolts came with the nuts on the left. It could be your tire mounted backwards or the rim itself. Who knows on such a old bike? The brake pads/rotors wear as a set. That's why the wheel should always be put in the same way each time.

I also forgot to mention your spark plugs. 5's are way too cold. Run 7's.

mspa 08-27-2012 06:56 PM

Hey guys, I should have mentioned up front that the bars are not stock, and I knew the barbacks were aftermarket. The handle bar is a American Superbike bar from Tucker Rocky that is 7/8", and I have no idea if the switch gear was hogged out.

I wish I knew someone around here with a similar bike to see what the diff is without bar backs. Honestly, I don't think I need them. In fact, moving the bars forward would allow for trying these bars at a different angle. I may try to rotate the switches tonight to see if that allows for some tank clearance. Otherwise, I need to find some risers that work with 7/8", or just wait to do this when I can afford a new bar, etc.

Re-Psycle has 11 rib gaiter boots for $24 each. I could pick some of those up in a month, but not sure I want to pull all that apart until I'm ready for my maintenance interval . . .

Spark plugs. Now you tell me!! ;) Those are new plugs. Man . . . well, what kind of a difference should I expect? I don't know how them running cold will effect the engine/ride.

Hmm, the tire needs to change on the rim. Makes sense. Now I have to decide if I want to keep the new Metzler I have. Without knowing how running a tire in the wrong direction effects ride, turns, etc., I don't know if I want to flip the used Metzler on there and see if I like it . . . then keep the new Metzler for when it's time to change. Or if I want to go ahead and sell the Metz, buy a Bridgestone to match the rear, pull the wheel, then put that new tire on. Confusing, eh?

sealsam 08-27-2012 08:43 PM


Originally Posted by mspa (Post 19453437)
Hey Samthg, do you have stock bar backs on your bike?

I'm not sure about this. This is what it had on it when I bought it last Nov. ...

Full tilt left ... This angle is a bit misleading. The pic makes it look pretty close. Aah, wait a second, it is pretty close but has never been an issue. Before I had the paint work done, there was a wear spot on the left side of the tank where the p.o. had a wire tie holding the clutch cable in place, and it rubbed.

I must say, I like the 'back' feeling so far. It gives me a similar seating and arm position as my RT.

...and shot with my 'cheap' Nat Cycle windscreen. But it works for me.

Times are GMT -7.   It's 02:01 AM.

Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2015