R1200S DOHC Project

[Stephen400]

I've fancied the idea of a 1200s for a few years now. So when this one was listed on ebay for £1300, well, who wouldn't jump on a deal like that!

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It had 107000 miles on the clock and it looked exactly as you'd expect. Mechanically ok, not perfect. Someone has painted it black and white, which is imo the worst part

The initial plan, as I don't currently have a rideable bike, was to fettle it and run it for the season. Then possibly do an engine swap/total overhaul.

Ideally I would like a liquid cooled R1200/1250/1300S but I don't think theres much chance of BM bringing one of those out any time soon.
I did consider making one of my own but this would be much more expensive and more like fitting R12S bodywork to an LC chassis.


I dropped on a 2019 R nine T engine with 3k miles. There was a special offer on at an ebay breaker. I think I paid £1200. Engine, gearbox, starter, alternator + Throttle bodies. Bargain! The DOHC is a much nicer engine overall, definitely the best of the oil cooled twins. Overall smoother and tighter feeling than the earlier engines (of which the 1200S is the best with its extra 20 horses )

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I threw it on the bench and tore it into a million bits...

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I bought a set of sunfaded Option 719 rocker covers. They were black and gold but faded to marker pen purple. I had them coated with Cerakote black and hand polished the edges back to aluminium.

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I sent the frame + subframe, swing arm + axle, Front wishbone to Triple S powder coating. I didnt send the wheels as I don't like the standard rims. I chose R nine T 5 spoke cast rims because I like the aftermarket look of them.


I discovered the 1200s exhaust is a larger diameter than the DOHC engine manifold so I had to buy a china special pie cut stainless downpipes. Im blown away by the quality and fitment. I will need to manufacture a link pipe in order to fit the underseat exhaust (standard for now. Akra in the future [i hope])

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Really struggle to get the colour on camera. Its powder coat, 'Illusion Purple' and its stunning

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The overall goal is to modernise the S BUT still keeping it an R1200s with the following:

DOHC Engine
LED DRL
LED headlight/indicators
Electronic Cruise Control
Possibly S1000RR mirrors (thinking the 2019 model ones may fit. dont know yet)
Custom colour switchgears
Probably loads of other bits

(As if they'd kept the model in the line up)



Theres much more to come. Let me know what you think

[dark_knight87]

Thanks for the post, will be interested in further updates.

Just a quick question? - will you be using the R1200 wiring loom or do you need to use the R9T's one?

Regards,
Russ

[ianc53]

Keep the updates coming, I will be very interested to see what it looks like when it's finished.

All the best

Ian

[f90x]

I think that was 'Humbug'. Well known here. I loved my S and owned it 11yrs. I always thought a twin cam version would be superb. Are you going to tweak the motor to get the 120hp of the 'twin spark'

[jeznewsome]

Cracking project. Thanks for sharing and looking forward to the next update

[Stephen400]

Just a quick question? - will you be using the R1200 wiring loom or do you need to use the R9T's one?

Im sticking with the R12 loom as theres very little changing electronics wise. The coils, injectors, lambdas, Crank pos etc are all the same. Even the newer style gear position sensor works with the S's bmsk and dash.

The only difference (so far at least) is that the Cam position sensor is different. A 3 wire hall sensor on the 9T and a magnetic 2 wire sensor on the S.

So the 9T sensor will not work with S bmsk and the S sensor will not fit in the 9T engine! Coincidentally, the 2010-12 dohc engines use a 2 wire sensor that fits in the 9t engine! I also had to replace the 'Reluctor ring' which is just a pickup on a washer, about £5 from BM.

I will be completely re-taping the wiring loom as its looking very crusty!

I think that was 'Humbug'. Well known here. I loved my S and owned it 11yrs. I always thought a twin cam version would be superb. Are you going to tweak the motor to get the 120hp of the 'twin spark'

Humbug... A fitting name!

I had a dyno run before the teardown, just for my own interest/records. It ran 108rwhp. Not bad at all considering the mileage!

I am interested to see how much the twin cam kicks out with the standard S ecu.

The main goal for now is get it running and see how it performs. Then a remap or Rapidbike evo.

I have also been researching a 1300cc big bore kit for the future... Not that its needed. 100bhp is plenty enough for a big twin to tear up the dales!

[f90x]

Yeah, a 1300 big bore would be interesting but not necessary. Looking forward to the outcome.

[popsky]

Looks superb now and it’s still in bits, looking forward to the project progressing. The bike possibly belonged to Sandbar who used to sell ilmberger carbon (I may be wrong though)

[Stephen400]

While I was waiting for the powder coating I started on the headlight.

I'm aiming for an LED halo type light, as you see on every new vehicle at the moment... But I like 'em.
I removed the front 'glass' (thats a nightmare of a job )

Here is the before:

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I painted the silver edging in satin black, I don't think it makes any difference to headlight output. Black certainly looks sleek compared to silver.

After several evenings designing, revising and printing different variations I came up with what I think looks very smart:

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The whole thing is 3D printed and uses a cob led strip and an led pilot bulb.

Im happy with the design but I still have to work on the wiring. I want it to fade on with ignition and fade out a few seconds after ignition is turned off.

I also want to make the low beam auto switch off with daylight. The drl would be wasted if the headlight was glaring away

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This was the beginning of assembly. Everything purple is powder coated. The front framework and front spring are powder coated black.

In an attempt to save a few quid I stripped and painted the fork bottoms and bottom yoke.

The suspension is currently Ohlins rear and hagon front. The bike came with the Ohlins front but it is damaged beyond economical repair. I had the rear serviced but it needs some components replacing to do the job right. I think for the money I'll go for a matched pair of nitron or yss or something else. Ohlins was a nice factory option but a lot of money to replace with new.

They're staying as is for this year.

I do love the combo of purple and yellow so I ordered a brake hose in yellow and purple. The yellow isnt a great match but it has grown on me.

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Here is the bike as it currently stands

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Im using the R12S throttle bodies as they're a larger diameter. They were beyond cleaning so I stripped them completely and sent them for powder coating along with the last few bits.

[Humbug]

Twas mine for 90,000 of those miles. Not painted by me I will add, although it stood out from the normal colours which did nothing for me anyway. Each to their own though. The Hagon replaced the front Ohlins which itself was damaged beyond repair when the bottom mount split clear in half. The rear had been rebuilt with new parts 10,000 miles prior to selling it, they are a bit prone to damage. Over the years, a few parts were changed, oil cooler, rear shaft, rear bevel box rebuilt, rear wheel to name but a few but the bike was ridden hard and fast both at Cadwell, Donington and across Europe a couple of times.
Nice to see it getting a new life.

[Stephen400]

Twas mine for 90,000 of those miles. Not painted by me I will add, although it stood out from the normal colours which did nothing for me anyway. Each to their own though. The Hagon replaced the front Ohlins which itself was damaged beyond repair when the bottom mount split clear in half. The rear had been rebuilt with new parts 10,000 miles prior to selling it, they are a bit prone to damage. Over the years, a few parts were changed, oil cooler, rear shaft, rear bevel box rebuilt, rear wheel to name but a few but the bike was ridden hard and fast both at Cadwell, Donington and across Europe a couple of times.
Nice to see it getting a new life.

Fantastic.

Quite a feat to hit those miles on an S. Theres no chance of me managing that

[Stephen400]

Not much of an update here...

Been waiting for Powder Coating for the last week.

Had a snow day yesterday (yes. like a child) so i had time to play with my 3d scanner. The DOHC engine has plastic covers below each cylinder to cover the secondary coil and wires. BMW want £25 a side! So after several hours scanning and printing I have a prototype that fits. Im thinking these might look good in Ohlins yellow? (its grey as its a prototype)

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I've just collected the latest batch of powdercoating.

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Front calipers in a slightly textured black.

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Throttle bodies, levers and end weights all in Illusion purple.

Got a bit of work rebuilding calipers (when the stainless bolts arrive) and reassembling the throttles...

[Humbug]

Wow, and black and white was the worst part in your opinion!

[Stephen400]

Wow, and black and white was the worst part in your opinion!

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Too Jazzy?



The way my budget is looking the black and white fairings might have to go back on

[Humbug]

Too jazzy for me but that's why I love the bike world, individuality. If you like it, it's good with me.