Honda CB250

Honda CB250, café racer/brat/Steve McQueen type of bike. This started out life as a Honda Superdream. This wasn’t a bike from my generation, so I didn’t know that every man and his dog has had one of these. Often called the “wet dream” due to the original spec being too heavy and in turn too slow. This was considered a reliable commuter, but not loved for its styling or performance.

The moment I saw it advertised I knew this was my bike. I took the afternoon off work and drove up north to pick it up. £850 –  in exceptionally good condition for a machine from the 1980’s, I thought this was a bargain. Everyone else thought I was mad!

Nearly everyone I mentioned this bike to turned their nose up straight away, and dismissed it immediately, but when I looked at it all I could see was an awesome bike waiting to be freed from it’s eighties bolt on plastic prison.

Again, as with every project I take on, I underestimated the extent of the work involved. I was quick to start, but had to park the project for what I thought in my head was a few months, but later realised it was more than a year. The European trip inspired me to get him finished. It would virtually be scrap if left in a million pieces, so I set myself a challenge to ride it before I leave.

The inspiration for the bike was to have a simple, uncomplicated machine that I could work on myself. I wanted a super cool bike that I could cruise down to the beach on and not have to dress like a power ranger. You do need a purpose for a motorbike. Otherwise after the initial buzz, you won’t ride it and there’s a high chance you will be convinced to sell it. The weekends are full of guys out on a ride, but with no purpose. Lets face it, they’re pretty inconvenient. The time you save filtering through traffic, isn’t really worth it when you have to carry all your gear. I wanted a bike that was light and nimble, something I could just jump on and ride to the local bakery on a Saturday morning in my tee shirt and trainers. Just reading that last sentence back, I sound like a proper knobhead, but that is genuinely what I wanted this bike for.

Inspiration – Steve McQueen

Firstly, I took out my hacksaw (not an innuendo) and chopped the back end off. I took my time on this, as this was probably one of the most pivotal parts of the build.

Stripped back the frame, all those bolt on bits had brackets of all shapes and sizes, but they didn’t put up much of a fight against my Bosch angle grinder.

Dropped the engine out, to give it a good clean. The ally block builds up a white corrosion, clean this off and the results are quite amazing.

Fortunately there are collectors for just about everything these day, so all the parts I took off were easily sold on eBay. I collected around £450 for what I called scrap, and as the saying goes, must have been another mans treasures.

There will be enthusiasts that will be crying into their thermos flasks knowing that I’ve cut up a genuine 7000 mile mint condition Superdream. This just spurs me on!

I sourced two complete stainless exhaust systems, the downpipes from Caferacerkits, and the silencers were from Armour exhausts in Bournemouth. Hand build in the UK these silencers were worth the money. Caferacerkits was an online find. They do a full kit for this model of bike, but I wasn’t keen on the other parts. Looked a little too finished, and doesn’t suit the bike in my opinion. It’s not a triumph, you have to be careful that you’re not trying to achieve something that it will never be.

I stripped off all the wiring harness, handlebar controls, battery box, plastics, centre stand, lights, indicators. Virtually everything. The criteria literally was if it’s not needed it won’t be fitted. I had always planned for this bike to be as simple as possible. I think I’ve taken this to the extreme.

I had a battery box built by Elite Fabrications in Poole. This turned out to be a really good addition. Perfectly designed to hold the AGM battery, start relay, horn relay, fuses, regulator/rectifier, ignition barrel, and horn/starter switch. Also formed the rear fender and gave a solid base for the single seat conversion to mount to. I found a really great short seat designed for a monkey bike, that gave the stubby back end that I was trying to achieve. I really wanted to have a floating rear seat, but I think that will have to wait until the next bike, it didn’t quite suit the bike, conflict of styles.

The air filter was one of the biggest lessons learnt. Not being of the carburettor era, I was ignorant to how good the OEM air boxes actually are. I bought two small cheap copy pod filters from the local bike shop, and assumed it will give more air flow, therefore better performance. I did have an inkling that the carb jets may not be sized correctly and the bike may not run very well, but I choose to casually ignore this concern, assuring myself it will be fine.

It wasn’t fine, the bike ran crap. Completely choked at 9k revs, and not exactly a smooth power curve in the bottom end of the rev range. After looking into carbs and air flow I found I needed to achieve a large volume of still air for the carb to draw from. The carb itself sucks in the air it needs. Having a pod filter gives loads of turbulent “un-useable” air, whereas the OEM air box gave a large volume of still usable air – far better and therefore more power, and that is the main purpose of customising your bike, to get it to go quicker. I bit the bullet and went for two genuine K&N RC 2900 filters. These were Oval shaped and gave a lager volume of internal air. The results were like night and day, it still has a flat spot at 8k revs which I think could be eliminated by playing with the fuelling, but the bike is more than useable. So when I have more time to tweak the needles and jets I’ll get it spot on. Ideally though I should have incorporated a plenum chamber design in the air intake, or at least a longer section from the filter to the intake, to smooth out the air.

I had to speak nicely to the MOT guy, as there’s a lot of grey area in the MOT rules and regs. They can be interpreted differently to suit your needs if you find the right person. The only issue was not having a brake light. Older bikes get away with a lot, but this was borderline. It scraped though as the bike was cool, but after riding it on modern roads, I think a brake light will be the next addition. Arm signals are fine for turning, but you can’t rely on your average driving gizzard to notice you’ve stopped.

Mission accomplished. I’m really happy with the bike. It’s a little underpowered and gets swallowed up on larger roads, but a for a hack around town it’s great fun. It draws a lot of attention, and I have a lot of fun riding it, which is the main goal. Costing around £1200 in total, I think it’s hushed a few of the non-believers.


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