GN250 to lightweight Café Racer … in a tent.

  

The trials, tribulations, tips, successes, failures, cock ups and maybe even the odd stroke of genius (correctly pronounced “luck”), all tempered with genuine impecuniosity and case hardened with a large dollop of Yorkshire parsimony.

My apologies in advance to all those grandmothers who already know how to suck eggs and to the builders who’s methods I don’t like. I lay no claim to knowledge or expertise, these are just my experiences and opinions and I am merely shooting the proverbial breeze here. You’ll also find a good few places where you want to stop and pronounce me an idiot. Fair enough, there’s been a lot of learning curve here and I thought it would be more useful to “fess up” and look stupid than to gloss over the mistakes.

Also, please either have patience, or browse through. I actually find every step of the process of building a bike fascinating, so I’m going to cover design, strip and cleaning, finding parts, re-design, paintwork, frame mods and eventually engine tuning and exhaust design. Just find the bits you’re interested in and skip over the rest.

The story comes in two parts. The first build, in a tent  (strictly, a garden awning) and against the clock, as I needed it for work. That covers pretty much everything on the bike. Then there’s the much more leisurely rolling restoration (still in a tent) where I get to go back and do it again, but better, plus design and build a new exhaust, possibly a few engine mods and, hopefully, some aerodynamics too. This may take a little time.

A bit of background

After putting another 40,000 miles on my 22year old Pan European (Honda ST1100 ) in six months, I did two things. I moved nearer to work and I decided that, since it deserved a bit of tlc,  I would buy a cheap little commuter to use while I rebuilt it. The rebuild couldn’t be instant (since I’m still waiting for a garage to be built) and the MOT was looming fast, so a 1995 GN250 was acquired for 350 quid. Three things were immediately apparent. I loved the engine, I love the fact that the bike is about the size of a dachshund and I hated the riding position.  I was forced to sit so upright that I was clinging on for grim death at anything over fifty, the long skinny forks and high bars made it feel like I was steering it via elastic bands and forward set footpegs  just don’t seem to work for me. When, on week two, it dropped a valve and wrote off the cylinder head (more on that very soon) it was clearly time for drastic action.

I still had two and a half months before the test ran out on the Pan (I wasn’t going to invest in new tyres before the rebuild) so I could do something about it.  I reckoned that you don’t need a lot of money, a fantastic amount of flash gear or a pile of money or a garage to make a fun little bike.

This is what happened next…

What shape to make it?

My first thought was that the ideal  commuter would be something along the lines of trail bike or flat tracker shaped. Admittedly, my new commute combined motorway and a large (and usually clogged) dual carriageway, but the chuck about style seemed like the way to go. I like the flat tracker look, so that was clearly the answer, until…

There is a great little web site called Cycle-ergo.com. It allows one to select a motorcycle, dial in one’s body shape and then see the riding position and tweak it about. Playing about with it revealed that any handlebar pattern higher than clip-ons would leave me sitting bolt upright.

OK, so it’s a café racer then. No problem, a bit small, but could be fun.  So…

Success Criteria

Every project should have a target, otherwise you forget what you’re doing it for and get side tracked, which in all honesty I probably will anyway.

1. Practicality – Even my new commute is roughly an hour each way, so I’ll be spending two hours a day on the bike. That means at least an hour duration without a numb bum, stiff legs or pins and needles in the hands.
    
2. Performance – I’m going for 80 square. By that I mean 80mpg and 80 mph. Not necessarily simultaneously of course, but without altering anything other than the riding style.
3. Looks – I’d like it to look good, but I really don’t want to be spending a fortune.  So I’m using stand off rules. When I was many years younger I used to fly model aeroplanes and there were lots of competitions for scale builders. Unfortunately bunging in fantastic levels of scale detail made the aircraft both very expensive and overweight, so unless they were huge they flew too fast. As a countermeasure to this a new scale class was invented.  The static judging was done with a “stand off”, i.e. from twenty feet away. That way they had to give the right impression, but the expensive detailing didn’t need to be there. I’m using the same approach on the bike. That means that I can buy cheap bits and don’t need to spend gazillions of pounds on chrome plating and such.  At the end of the day, it’s a cheap commuter.