Jim Ewen's blog

3. Should I be here?

Jim Ewen — Tue, 28 Feb 2012 20:33:01 +0000

Should I be here? I see a comment suggesting that this stuff should be elsewhere? No probs with that, and if the Moderator (or whoever…) suggest that I dump this to some other place, please give me a link and I’ll do that. Not sure I was needing feedback…really just posting in case others wanted to know…what not to do! In the meantime, I always thought of the old site as just that…’old’…and this was the newer, preferred one. And since this one prominently said ‘Blogs’ on the LHS, I assumed I was in the correct place…but I’ll take advice…

Mk III…. Why? An upside of getting older is that you tend to have more spare bucks. The downside is that you are more careful and sensible about spending them. Add to the mix the cultural myth (?) that Scots are mean, and that takes you (OK, me…) farther down that path. And in Scotland, the meanest-of-the-mean are reputed to be in Aberdeen area. Yup; that’s me as well. So, despite a long-term obsession with an Ecomobile, and life putting me in a position where a second-hand one might be a possibility…would I commit?

Mmmmm. Lot of money. Would I use it? Does it feel like giving in? Would I feel a wuss for not trying to build something for myself? Was the building likely to be more fun (and maybe the bigger objective?) than the owning / using? Too many questions. Final decision was 1) try to build something and 2) if that fails….potentially buy one (Could I? Who knows).

This overall situation was not helped by the death of two acquaintances (in as many months) in bike accidents. It appeared Mrs E would rather see me labour in the garage for two years than be on the road too quickly. Short-term decision made = Build.

Design Intent; this took some time. I had to be clear why I was building this and for what purpose. Much as I’d like to claim otherwise, my days of leaving boot leather and footrest alloy on the tarmac are largely gone. My reactions will be too slow (I don’t think they are…but they are…science and fact overrules fond delusion), the roads are busier, and my need to compete / race is now in control (usually…)

I’ve also learned from my car driving. I once travelled everywhere at 80mph+. I now tend to travel at 65~70. And guess what. It’s more relaxing. More economic. No less fast. No less fun (generally…) ‘I Must Learn…’ In designing this bike I had to be realistic. It was not for town commuting. It was not for scratching. It was for recreational (= pointless except for enjoyment) riding in the summer. Mainly open road, around 50~70 mph, with towns by exception and cities by mistake…weatherproof…or at least weather resistant

Motorcycling Tastes; I rode trials and enduros when I was younger, and though sucked into the Bultaco / Montesa / Ossa world, always liked the (then obsolete) Greeves Hawkstone / Scottish / Pathfinder, with its cast alloy downtube and leading link forks…

My car choice then was also a bit awry. Not the ubiquitous Mini, but a 2CV…which I thought was an(other) example of great and innovative engineering. I lived in it for a while (built an extended tailgate, no passenger seat, and had a bed & stove in there..) and further converted it to carry my trials bike inside. I still think that type of car has merit, more so as we build complication and unnecessary luxury into newer designs of cars. (Remember ‘Africar’, anyone?)

Bikes were there too. After being briefly sucked in by GS750 and GS850 Suzukis, I fell into BMW airhead boxers, and big Guzzis, which I had on and off for the next thirty years. I bought many bike mags, and all things came and went, but when I read of the Quasar when they first appeared in the late 70’s, I was utterly hooked; this was Goooood. Didn’t know why, it just was.

I was always drawn to the unusual, of various flavours, and saved up clippings and articles of the Munch Mammut, the VW based Amazonas, the 1980’s De Cortinze Honda Elf endurance racing specials and the Moto Shifty etc. (Pity so big; must be a Better Way)

I eventually owned a Shifty…same one as Superbike mag tested (BAB 868 W…where are you now…?) Some great ideas and some dreadful ones….the H-pattern foot change…tank under the seat.…the locking-out of reverse gear…(when it was heavy to push out of the gutter when parked nose-in, Duh!)...the width which was the same as a BMW boxer…and the use of a Fiat 127 engine and gearbox; great engine…but cast iron! The killer, however, was 1970’s Italian Laverda chassis and cycle parts propensity to rust….

So What Power Unit for Mk III? I love articles in bike mags on guys who build their own engines etc. Way beyond me. Logic also says why (unless for personal satisfaction…which is quite understandable). Whatever you want, it has already been done, and generally better as a consequence of mass production and economies of scale / mass purchasing power.

My own ‘ideal’ for this new project was to be diesel, and automatic, ideally CVT. Eventually diesels did not happen for me in this case. Generally (especially for industrial engines), they were too low on power for their weight.

Automatics for the same reason; weight and bulk. Most likely choice would be a car unit + gearbox, for lots of reasons, not least availability and support. Some of the current three-cylinder car units must be a future possibility, such as VW, Daihatsu and GM…but too many complications. For now.

Complication was to be a recurring theme. I felt I was taking on enough in this project without taking on more complexity than I needed to. If this project ‘worked’, even to the point of it being vaguely useable, them Mk.IV could be more ambitious and precise. This principle saw me finally go for a BMK K series engine and box. Why? The Brick was also in plentiful second-hand supply, had a long production run, was generally reliable, water cooled, and the engine / box / swing arm unit could be left largely as-is, reducing my ‘challenges’.

I wanted a 750 triple…I felt that had the optimal power, as well as better balanced…but the four was easier to get. And my mate had one potentially for sale around that time….

It was not the ‘best’ choice. The length of the unit means I was stuck with single-seater if I wanted to go no longer than a notional 2.4m wheelbase…alternative calculations showed that I could have hit my notional 2.4m limit and had two seats, had I used a Jap across-the-frame four. Probably was down to a predilection for BMW…and it simply being there. Add to that the retro-grouch factors, and the fact I saw the K as almost ‘space-age’ compared to airhead R’s, then I was approaching my technology limit with a K….

2. Someone asked for more....

Jim Ewen — Thu, 16 Feb 2012 21:04:03 +0000

Out of sequence…

I’ve a couple of bits written, but it’s still ‘lead in / whimsy’ stuff, which might work if you are patient, killing time or like a meander…but might be boring as sin if you want to get to the greasy bits…so I’ll ditch some of the run-in stuff this post and add it in next time, flipping between the two genres in subsequent posts, until we are exclusively in garage + welder territory…

My Early FF Attempts

I mentioned that I was into attempt Mk. III at a FF. That’s maybe a bit dramatic. Mk I was a long time ago and would have been a Fiat 600 engine from a car I had from which the body oxidised to transparency...but with a great engine. That saw the Fiat 600 vertical twin (it was good…) mated to a Norton gearbox (it was there…) and all sat in a modified Suzuki frame (it was cheap….) As to where and how I sat…I wanted a better way, but never gave it enough thought, and made it up as I went along…never a great method! Think maybe I started off that project in youthful enthusiasm more than thought and planning…and it ‘died’

That was followed, twenty years on, by Mk II, a notion of designing something which would do 70mpg at a steady 70mph. That felt like a good design brief / challenge to ponder over. Some very rough calculations metered by guesstimating suggested I’d need around 25~30bhp and significant streamlining / reduction in frontal area.

I wanted to use a 2CV engine (as being unburstable, frugal, available, simple and alloy…tho’ ‘of it’s time’, hence low efficiency) and drop the CoG more for reasons of frontal area reduction than handling. The biggest ambition was to build leading link forks…which felt the ‘right thing to do’, but I wasn’t sure why. They worked, and seemed easy to get right, and the bike got to rideable rolling chassis stage…but the arrival of a brace of other projects at the same time, with attendant space pressures, saw this get neglected to the point of disposal

The current and Mk.III attempt, which is maybe about 30% through, is the one I’ll take some time outlining in coming posts.

Does anyone else suffer from this ‘shed-builders’ characteristic? A s**t day at work. Come bedtime, you slither in behind your wife / husband / partner / dog and slumber off to sleep, whilst happily thinking about how you are going to solve the particular nagging garage problem of the moment. I love it…

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Chapter One?

Jim Ewen — Thu, 09 Feb 2012 21:23:32 +0000

I’ve been around the periphery of FF, looking in, for many years. I’ve had two abortive attempts at making a FF for myself, but am now half way through Mk III, and for that, as well as various other reasons, have been back to this site, and read…and re-read…and read once more…a great number of articles around this subject. It was only recently that I looked at some of the blog dates and they seemed…errrr..’aged’. My conscience was pricked. It seemed wrong to hoover up all of this stuff from others and not add back in my own experiences…even if they were only to help someone else avoid my errors, or to pass on some bright ideas (?) which I might have tripped over and which someone else might be able to use.

So here I am. I was of a mind to dump some stuff on here and (sloooowly…) bring my own FF story up to speed, though if there is a glorious silence on the early posts…or politely veiled suggestions ‘that I desist’…then I’ll happily bu88ger off back to the garage and forget it…on the other hand, if anyone finds it either vaguely interesting or sporadically useful, I trust they will say so and I’ll keep on going. It’s likely to be a meandering story over a few weeks or months rather than a technical treatise

Please be tolerant; I do slaver on a bit, and right now I have a few trips where I will have time on my hands, thus will be able to add to this…so don’t expect many pithy one-liners… I’m not great at ‘concise…’

Early posts will be short on pics…but I’ll add these, perhaps lagging the bits I’m talking about as I have time and opportunity. The project progress is in delay (naturally...) due to 1) work, but exacerbated by 2) CGWS syndrome (Cold Garage Warm Sofa…) when I’m at home, and 3) MITW (More Ideas Than Welding) when I’m away on business

Maybe people should not read in too much from the early posts. They will be around why I take this route; I think that matters. It is always easy to buy only what’s on offer, what marketing tells you to buy, or buy your way out a problem…but in my case at least, I want Different, and the fun of getting there and solving the tiniest problem, this being as much fun as the ‘having’ of the final product

Bored yet? Don't worry...you will be soon!