Total Pageviews

Friday, 27 February 2015

Restore or recommission?

I've only restored one bike in my life. It was a Honda CB92 and it was so nice when it was finished that I couldn't bear to ride it. My OCD went into overdrive and I started to poke bits of dust from its crevices with a cotton bud. It was sold to someone who didn't have my issues and I suspect they gained as much enjoyment from it as I did anxiety attacks.

All of my other bikes have been recommissioned.  Now to some, recommissioning means an oil change and a wipe over with WD40. For me, the object of the exercise is to end up with a bike which looks old but cared for. A bike which starts, stops and rides exactly like it should.

This only works if you choose the right bike in the first place, namely one that is reasonably tidy and complete. Paintwork has to be sound as any repainting spoils the overall patina of the finished bike. As soon as you paint a tank, the original seat cover looks tatty and as soon as you re-cover the seat, the chrome starts to look bad. Before you know it, you're on the road to restoration.

Mechanical issues are not too much of a problem as you can blend the repairs in to the overall look of the bike.

I've been working on a low mileage BSA B50ss which luckily, had no major problems, but still required lots of deep cleaning and a fair bit of money throwing at it. A tin of 20/50 and an oily rag may be cheap, but properly recommissioning a bike is not. Here's a list of the main bits I had to replace in order to get the old girl sorted:

New Amal carb - £130
New oil lines - £20
New Motobatt battery - £70
New kickstart quadrant - £80
NOS chaincase - £150
New chain - £30
All new cables - £90
New petrol taps - £25
Pipe & in-line filters - £12
New handlebars - £35
New grips - £12
NOS air filter £40 (!)
Airbox - £30
Carb to airbox rubber - £12
New tyres - £120 (not fitted yet)
Allen screw set - £20
Gaskets - £15
New oil strainer - £20
Oil - £20

So that's a whopping £931 plus about 40 hours of cleaning, servicing and fettling. Was it worth it? Absolutely. The end result is a cracker of a bike which looks really nice and still retains most of its original finish. It rides like you'd expect with such low mileage and the great thing is, there'll be no problems taking out in the wet or even getting a bit of mud on the tyres.

If you're into BSA unit singles, there's a really good forum at:

Thursday, 8 January 2015

Aspen - Because they're worth it

I don't know about you, but the thought of crappy petrol and ethanol gives me nightmares over the winter months when my bikes are laid up. I've tried or considered a few options since this became a problem.

Drain the tanks? Then you have a bare metal tank which to me isn't that good an idea. Also not kind on cork washers in fuel taps as I found out to my cost when they shrunk beyond repair and needed replacement.

Stabiliser? I find it hard to believe that a 1-2% mix of anything will fix all of the ills of modern fuel and prevent corrosion due to water content.

Fill the tank to the top? Hmmm. Even more fuel and more water hygroscopically absorbed by the ethanol.

Luckily I have discovered a better answer. Aspen is a pure petrol sold in 5 litre containers designed primarily for use in garden machinery. Putting aside the fact that it is way more environmentally friendly, it has NO ethanol and is so pure and stable that it lasts for five years before loosing any potency. The downside is cost, but at around £18 for a once yearly five litre slosh, its a damn sight cheaper than a new tank or an ultrasonic carb clean. Aspen is available in straight petrol or 50:1 premix. Get the blue can and if you need to put 2 stroke in it, you can mix your own ratio.

I've just drained all the rubbish out of my tanks and installed a can of Aspen in each bike and flushed it through to the carbs. No more sleepless nights, and as a bonus, you end up with a very nice re-useable container to store pump petrol for the car or mower.

Here is a link to the Aspen website:

Wednesday, 7 January 2015

B50SS - The Bike That Dare Not Speak Its Name

When I was 14, I had a poster on my bedroom wall which featured an OIF BSA A65 Lightning and a B50SS. I've never really paid much attention or registered any emotion for these bikes since then, but these things must have a profound psychological impact because when I stumbled across this bike for sale in December I just had to get my hands on it.

Unbelievably skinny and very light at 140kg, the B50 was the very last in the line of British 500 singles, and as such deserves a place in motorcycling history. With a punchy 34bhp engine and 'trail' styling, its looks were somewhat ahead of its time.

Controversially, BSA decided to add the 'Gold Star' name to the SS, which deeply offended DBD owners. To be fair, as well as setting a TT lap record and winning its class in both the Thruxton 500 and the Barcelona 24 hours, the B50 (with assistance from CCM) went on to have an illustrious off road competition career so maybe in hindsight it has earned the right to use that sacred title.

I think I'll to refer to it as a 'Goldie' just to annoy people.

My example is an American import (as most are), with only 11,000 miles on the clock and is in very original condition. I'm not going to restore it, I think that would be a shame. Just a thorough re-commission and a good clean and polish should result in a nice, useable bike with some patina.

Tuesday, 6 January 2015

Amal Carbs - The Proper Way To Restore A Distorted Flange

I'm in the process of bringing another bike back to life, and as usual the Amal Concentric carb has been over tightened. As a consequence, the flange is warped. It's a low mileage bike and the carb is surprisingly good, so it's worth fixing.

Now the obvious thing to do would be to get a sheet of glass, some 400 grade wet and dry, and rub away to flatten the flange. Obvious, but not really the best way. A more effective solution is to use an accurately made tool to apply the opposite pressure to push it back into shape. Not only will this bring the flange back to true, it will restore the shape of the rest of the body which has been distorted.

I made the tool a few years ago and it has rescued quite a few carbs from the scrap bin. The base is a flat alloy block with a threaded rod fastened securely into the centre. The 'slide' is turned from solid alloy and is machined to fit the carb bore accurately.

You simply pop the 'slide' into the carb, feed the threaded bar through a hole which is drilled to be central to the inlet and then as you tighten the nut, it pushes the whole thing back into shape. A pair of of 5 or 10 thou feeler gauges (one placed below the mounting hole on each side), allow you to bend the flange past straight so that when the nut is loosened the natural spring in the metal will leave the joining surface and the body absolutely true.

With the aid of this simple device, it takes about two or three minutes to fix a carb properly. If you work on old bikes regularly, it's well worth knocking one up.

See this link for information on how to install an Amal carb:

Wednesday, 19 November 2014

When It Comes To The Crunch...

Like most enthusiasts I have far too many bikes, and as a result they don't get the regular use that they deserve. One of the consequences of this is a nasty and potentially expensive crunch when trying to engage first gear after anything other than a few days lay up. This occurs on a couple of my bikes even after much kicking and rocking to free the plates.

My first attempt at solving this on the Comet was to spend £450 on a new Conways Honda clutch conversion. This runs in ATF and is set up perfectly. Unfortunately it didn't work.

The second attempt involved a 2p cable tie, and this has proved far more successful. Let me tell you more. I was chatting to an old guy a couple of months ago and he suggested a simple, but quite brilliant method of eliminating this. Just get a cable tie and fasten it loosely around the handlebar grip and when you leave the bike for any length of time, use it to hold the clutch in. Since I've done this with my crunchy Comet, the difference has been remarkable. Not only has the noisy first gear been solved, but the gear change as a whole is vastly improved to the extent that I now realise that I don't need a new gearbox.

Granted, over time it may weaken the clutch springs (we'll have too see), but I'd far rather replace them than start buying new cogs for a Burman gearbox.

Quick Review - Replica Miller Ammeter

A genuine old Miller 2" ammeter in reasonable condition will cost you anywhere up to £150. If it's a 'Lighthouse' you may have to shell out a little more. There are many new replicas listed on eBay, but how good are they?

Well I'm pleased to say that they are not bad at all. I purchased one as a replacement for a cracked and  brittle original and for the very reasonable price of £33 it's a pretty good likeness and looks to be good quality. From more than a couple of feet away you'd struggle to tell the difference, with only very slightly thicker text and a stainless steel bezel marking the 'fake' from the real thing. Make sure that you get the shallow case version, or you may find that your headlight reflector fouls.

OBB seal of approval awarded.

This is the real thing

This is 20% of the price of the real thing

Quick Review - New Doherty Levers

I recently decided to get new clutch and brake levers for my Vincent Comet, as the old ones were not only worn out, but had the wrong fulcrum length. Throwing caution to the wind, I decided to go for British made Dohertys at the whopping price of £60 plus post for the pair.

Sadly, it seems that British craftsmanship ain't what it used to be. Finish on the blades is poor, the chrome plating on the levers is flat and thin. The threads for the mounting clamp are metric, as is the pivot screw, so this means that I can't use the nice stainless BA screws from the old levers. Other than that they do the job, but I'd have been much happier paying half the price for them.

It's sad when a once illustrious name is tagged to sub-standard goods.

So, what is fulcrum length? Many people are unaware that levers were originally specified with different 'pull ratios'. The distance between the centre of the pivot and the centre of the cable nipple was available with 3 different measurements - 7/8", 1" and 1 1/16". The longer the measurement, the more pull and stiffer action, the shorter the measurement, less pull and easier action.

If you have a dragging or stiff clutch, it might be worth checking that the levers are to the correct spec. It's also an effective way of 'tuning' the feel of your front brake. It won't solve other problems, but it may well help.