K75/Boxer FF

Not sure if this is the right way to do this (perhaps its a FF entrance exam, that I have failed)
I rather fancied a FF motorcycle with either a K75 or Boxer engine.
Any idea how I would start such a project. I have access to engineers/machine shops at work but only have mechanical skills myself.
I guess it may be easier to buy something and covert or at least ride around to get some ideas.
Where may I find auch a thing ?
I presently own an R1150GS, a K75s, an R65, 2 velo 350's a Suzuki 600, a Moto Guzzi Stornello 125 and 2 Yamaha RS125's.
I also have an ex Police R100RT that is for sale ('83 £1200) but may do a p/x on this or any of the others.
Was just reading an August 1980 Bike magazine with Royce in the Isle of Man on Quasar. He was always a hero of mine and I guess I am the same age now as he was then.
What is he up to now ?
I spoke to a Panther 600 owner at Sammy Millers museum who said Royce was into some kind of T.E.Lawrence trip, riding round on a '36 SS80 Brough in a pre war RAF uniform (sounds a bit unlikely to me)
Anyone doing the Welsh National Rally on the 7th May ? maybe meet up somewhere

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Boxer FFs

I started a boxer ff (R75/7) many years ago, and though a bad smash, then a wedding, kids & a 5 year diy to-do list have prevented completion, I may be able to suggest some courses of thought if you want to cut up an old one.

Many people in ff-ing dismiss the boxermotor as too wide. To use it you have two choices: a) sit in front of the engine, making it either very long, as Booleroo (?) , or too high a seat to get the benefit, or b) sit on top of the gearbox and do the frame mods.
I went this second route which maintains near std wheelbase.
Obvoiusly you have to cut the frame spine away, compensated for by opting for Hub Centre Steering, which reduces the torsion in the frame by a guesstimate of 10x. The main frame loops are very heavy tube, and I thought with the crankcase bolted in tight they should be stiff enough. I welded a subframe onto the bottom of the front fame loops to support the lower swinging arm, and made an upper one just below the steering head. Then I added removable bracing tubes from here back to behind the gear box, as per sporting BMW practice.

Net result :
c18-20" seat ht depending on amount of foam used,
60" wheelbase.
Std power train, inc exhausts, only requiring K&N filters on the carbs to replace the air box. Plenty of capacity/ final drive options.
Surprisingly ergonomic for my 5'7" frame.
Low engine allows a flat platform for a simple folded steel fuel tank, c4 gall in the cardboard version, easily stretched to 5 galls.
Potential for miniumum wt gain, before the fibre glass is added.
Can still use Krauser panniers.

Possible weaknesses:
Possibility of grounding the heads if it's any good!
Only a single seater.
Having to put your foot down wider than the bike, But you can rest the (insulated) cylinder head against your knee, which may be very strong bracing position -- but it might break your leg if the thing still fell over!
Needs grp to duct air onto the pots, and stop your knees frying in traffic.

Sourcing a HCS, mine is a pile of spare bits from the late Malc Newell. (which was not as easy to use as it was supposed to be).

Plus a 30 year old engine design etc etc.

I hope the gives you food for thought.


Thanks for that, would be interested in looking at your project.
I am based in Herts/Mid Wales but travel around quite a bit.
my e mail is andrewdockree@yahoo.co.uk

BMW based FFs

Hi Andrew,

We are building BMW K- based FFs in Berkshire, our prototype will be on the road in a few weeks, see the Yahoo FF list for a picture of the nArrow 'Escape' tourer; uses K1100 16v drivetrain complete (driver over bell housing, passenger over rear wheel)full bodywork (inc roof and doors of course)car seats, belts, safety cage, boot and internal panniers etc.

To overcome the shortcomings of stabilisers in a properly enclosed FF we went to two front wheels, hence nArrow is a 'Tilting Three Wheeler'(TTW) (for more TTW stuff see Yahool Tilting group) our new website will be up in a week or two also FYI.


Roy Gardiner
nArrow Vehicles Ltd.

BMW-based FFs

Andrew, have you checked out the Booleroo Boxer FF and the Dodds K1 FF in the one-offs section of the site?