R100RT to RS fairing swap

[NMBeemer]

I bought an '84 RT and am swapping the upper fairing out for RS pieces. I will list the RT fairing, mount, and a new RT Parabellum windshield for sale on the buy/sell page when I get a moment (first photo - dunno why the thumbnail is upside down but the full-size is right side up...)

I have test-fitted some of the new panels (2nd photo) and remembered that I need a different upper mount for the RS bits. I found one for $35 on flee bay, so that's on the way.

The paint is close but no cigar, so whenever I get a week free, I'll repaint the fairing, fenders, tank and side covers--which have the wrong decals on them now. There's also the badge on the rear fender I will have to swap out.

I have a flat bar from an old British bike I was working on and decided to go with clip-ons, so this afternoon will see if that'll work out...

[NMBeemer]

I cut down the 7/8" flat 'drag' bar I had fitted to the Bonneville to a little over 24", as I think I've read the OEM R100RS bar is 24" wide. (The comparison photo is before trimming.) Looks like it'll work fine, though the RT master cylinder contacts the fork tube cap, so the reservoir is canted back a little and the lever is dead level. I'd rather have my levers aimed downward a touch so my wrists are straight.

The lever tips are very close to the fairing as you move through the steering range, but don't contact the plastic before the rubber boots start to limit your travel anyway.

All of the cables are going to be fine in RT lengths. The electrical leads can just get routed slightly differently and re-zip tied to look nice. The clutch and choke cables will work but need re-routing--which leads to a question: how do you get the clutch cable out of the lever? Ordinarily, there is a slot in the adjustment barrel and in the lever, but not here.

The brake hose (which indeed looks like an upgraded braided hose) needs to come off and get re-routed around the fork tube or perhaps just loosened and the banjo pivoted to net a more relaxed radius. But I think it'll work.

Hmmm... on the handlebars I think I'll see if the studs will come out of the aluminum clamps. If they will, I can just get some longer ones and fabricate spacers from aluminum bar to lift the bars up just a teensy bit, to allow the controls to pivot a few degrees forward, improving the hand/wrist comfort and leveling the master cylinder reservoir.

I'm leaning toward GT grips like I have on the Bonneville. Thicker toward the center and narrower toward the ends, which some padding for your palms.

Waiting on the RS upper mount, which is coming by s-l-o-w shipping...

[srankin]

Looking forward to the report, St.

[NMBeemer]

So, still waiting on the headlight/upper fairing mount from the UK...

In the meantime, I was perusing the OEM shop manual I got with the bike and ran across pages with data on the handlebars. I had cut the flat bar I had lying around to a little over 24" based on what I saw on websites still listing a bar for the RS, and that looks like it'll just barely clear once the fairing is held in the center by the mount. But I see here that the RS came with a (gulp) 21.6" wide bar. Wow, that's narrow...

Anyway, if the tips of my clutch and brake levers scrape toward full lock, I guess I'll just trim a bit more off the ends of the bar to bring it into spec--or as close as needed to work with the RS fairing.

Anybody got an RS with the OEM bar who could measure theirs tip to tip? I believe the measurement is straight across, not following the curvature of the bar.

[NMBeemer]

All rightee then...

I went ahead and ordered a new OEM bar, as the bends of this cheap flat drag bar I had lying around just don't cut it: I can cut it down further to match the width of the OEM bar but can't rotate the controls sufficiently to have the levers at the right angle. So, it'll be box-stock RS in that regard...

New GT 'Beston' grips came in, so I'll be fitting those when the new bar gets here. I will also install the new throttle cables the PO has in the box 'o parts, and clean/lube the chain-and-cam mechanism, which feels gummed up and won't retract fully on its own even after loosening the thumb screw all the way. Decade of non-use, I guess.

The upper fairing mount from the UK gets here (supposedly) on Thursday the 21st. So, I should have the conversion completed that weekend--which will include the nifty Katdash that SRankin was nice enough to let me know about. I will then ride down to the State PD for the VIN inspection, so I can title it in New Mexico.

The bike's going to need new paint at some point but as it isn't gosh-awful, I'll be satisfied with (maybe) new Rondels for the next year or two, while I finish the Bonneville and then wade into an engine rebuild on the '51 FL. This bike is intended to be my go-to commuter into The Big City from my mountain hideaway in the Sandias, so it can wait to be prettied up...

When it does get paint, I will probably change from this silver--which really looks gray. It's okay but I'd like something less... well, gray.

[NMBeemer]

On the paint: I already have a black bike and a blue one, seen here. So, a less leaden silver than the OEM hue the BMW currently has might be nice, or maybe something else altogether, perhaps more colorful...

BTW, they're all pushrod twins, but the Beemer is the only one that doesn't have a 360-degree crank, does have an electric start, and did come with disc brakes--so I don't have to design yet another DIY front disc setup. Very nice...

[NMBeemer]

Okay, received the OEM RS handlebar this morning and installed it... wow. Can't wait to ride the bike with this (in my view) far superior riding position. The OEM seat feels like it'll be much more comfortable with this European, slightly forward canted riding posture. On the 1,300-mile jaunt back from Wisconsin, the curvature of the seat kept scooting me forward when in the bolt-upright RT posture, essentially... well, bunching things up uncomfortably. This will be far better on longer rides.

The Beston GT grips feel wonderful, too (see 1st pic). The cushioning and shape are superior to OEM BMW grips if you're going to be leaning lightly on the bars, as is the case with the RS riding position.

Also: I cleaned out that awful, gummy gray grease and applied Slick Honey bicycle grease (2nd pic), and the throttle return is now crisp and immediate. No need to install the new cables the PO has in the box-'o-parts.

Finally: Brook is wrong, in that you do not need to change out any cables, wiring, or brake hoses. Everything works just fine if you simply redirect things a bit.

[srankin]

Changing out cables depends on a number of things, Brook has his ideas when to do so and he makes sense. The bikes he restores have issues requiring the cables to be changed. You got lucky your cables are in good shape. Maybe the PO changed them at one time but neglected to re lubricate the twist grip.

Each used bike to a new owner comes with some degree of previous owner's disease. A good PO did things right, was proactive on maintenance so the new owner gets a bike with few issues. That is great! Sometimes the PO is mixed on skill and knowledge, most common way of the world.

Glad to see the progress, have fun. St.

[NMBeemer]

Changing out cables depends on a number of things, Brook has his ideas when to do so and he makes sense. The bikes he restores have issues requiring the cables to be changed. You got lucky your cables are in good shape. Maybe the PO changed them at one time but neglected to re lubricate the twist grip.

Each used bike to a new owner comes with some degree of previous owner's disease. A good PO did things right, was proactive on maintenance so the new owner gets a bike with few issues. That is great! Sometimes the PO is mixed on skill and knowledge, most common way of the world.

Glad to see the progress, have fun. St.

Yeah, I think you're right. Certainly, this bike is a mixed bag but the engine and tranny seem to be sound, and that's the main thing, for sure.

[NMBeemer]

After a month and a week, Max BMW sent me a shipping number for the new OEM RS windshield and gasket. So, I darted out to the garage to see if I could get things ready...

I have to say this is a fiddly fairing to install, but quite rigid once all the fasteners are in. I've seen RS mirrors drooping in some videos, but these seem reasonably tight on their ball joints and I think they'll stay in place. Based on the view in the 'R100RS flat out' track day video I posted not long ago, seems like the view they offer at speed is fairly vibration-free, too...?

I did not R&R the fork tubes to install new gaiters, as these are not yet that brittle. But we'll see how long they last. Just used some scotch brite to clean up the upper tubes a bit.

New stainless braided rear brake hose and Brembo pads, new rubber braided reservoir hose with good EFI-spec clamps, not that yucky crimp-on style. The rear caliper seemed like it was frozen, so I popped it in half to R&R the pistons--but it proved to be working fine. So, a little O-ring I had in an assortment, and back together it went. No leaky.

I've left the headlight boot and glass out in order to more easily aim the (now LED) unit--but otherwise, it's all put together. I'm only missing the two bolts that connect the lower middle to the upper, and which are larger than any of the others, weirdly...

Can't wait to zip down to the MVD for the VIN inspection--a 25-mile ride beginning with a twisty canyon--to see how it is behind the RS fairing.