Category Archives: Uncategorized

Building a Rotating Motorcycle Engine Stand

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Since time immemorial, I have stripped and built engines on the bench or on the floor…

…and it’s a royal pain in the backside. Trying to balance the thing at suitable angles, hefting it about, running out of hands at every turn and of course, that searing pain when you realize which part of your anatomy it was resting on when you hit it.

But no more, I say! Rupert Ratio has a drawing for a decent one, which you can lay on its side, in the back of his book.
Before embarking on production I had a quick look at fleabay (it’s often cheaper to buy than build) where I saw a truly snazzy one which rotated through about 300 degrees.
On closer inspection, it had a couple of drawbacks. One was a fairly substantial price tag and the other that the rotation was locked by a bolt through a radial slot in a circular plate. This means that only the friction applied by the bolt would be holding it, which just didn’t sound quite enough when you start riving on the thing with a big bar, or even have to tap something off/out.

However, this is the backyard builder and suitably inspired I headed for my various scrap bins to see what I could find…

I have to confess that I bought some bits. Actually two steel discs (offcuts on fleabay, presumably out of the middle of something with a hole in) and two M10 nuts and bolts.

To action!

The steel discs were marked out thus…

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For marking out rough stuff I love my little white paint pen. It’s nowhere near as accurate as engineers blue and a scriber, but a lot less messy.

Then bolted together, stuck in a vice and attacked with an angle grinder.

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A chunk of square section provided the next bits. Chopped up and drilled as below…20171007_123626

A quick zap with the welder renders all the nuts captive… then the channels get glued to the discs

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Now I need something to hold them off the ground…
I cadged half a dozen four meter lengths of this heavy walled tube from some chaps who were chucking it in a skip. It used to be handrail in an industrial unit. Keeping your eyes open and have a bit of cheek can save you a fortune.

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But beware, welding galvanized steel produces lethal fumes. I make sure I grind all the zinc off the outside and since I don’t have an enclosed space to weld in I reckon being a bit careful will do for the bit on the inside. You may want to clean that off too.

Once it was tacked together I chopped it in half…

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Because, by a fortuitous miracle I just happened to have a few yards of this size tube as well

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Which is what I’d call dead jammy.

So, with a couple more bits stuck on, I now have an adjustable width standy uppy bit, to stick my roundy roundy bits to.

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Now, if you’re going to build one of these, I suggest you ignore the next bit, because it’s where I came up with a stupidly complex solution to a very simple problem.

I bolted the disk to the upright, so far so good…

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Then produced this natty little pawl mechanism, involving lots of cutting and folding, which I welded to the top of the pole.

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And it works a treat. BUT…

If I’d just left the pole a bit longer (like I did on the other end) it would have been a helluva lot simpler…

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To just stick the pawl in a slot in the pole. Then fashion a little spring out of piano wire to hold it in place.

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But only put a spring on one end, or you’ll need three hands to rotate the engine!¬

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A few bits of plate cut out and bent, provide the right mountings for the engine. Which just bolt to the captive nuts in the channels on the discs.
The width is adjustable anyway, But I measured the ones on the bike to get the right range. The height difference I took from RRs drawing, but isn’t critical.

I also decided that it would be a good test bed for the paint I’d decided to use on the B40s frame. So a coat of etch primer and a splash over finished the job.

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One huge, and unforeseen, advantage of the two part construction turned out to be the incredible ease of mounting the engine. You never have to actually lift it up. Just tilt it back to put the front in…

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Then swing the back up and slide the other end in place

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In use, I have to say it’s wonderful. Not that mine’s any better than anyone elses’, but having one is wonderful. I don’t know how I ever lived without one.
It seems to be stable at any angle and has handled sockets with a big breaker bar and some genteel tapping with no problem whatsoever.
I’d definitely recommend the extra effort of the rotating mechanism. It ain’t difficult and being able to instantly set it to just the right angle to reach bits (or stop them falling out) is a real boon. It’s odd, but it’s one of those things I probably wouldn’t bother to adjust if I had to take a spanner to it, but it makes life so much easier.

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BSA B40 Rebuild, Order of Play, Getting Ready

It’s well worth scribbling up a list of everything you can think of well before you start on the job. You will, of course, miss some bits, but it will nonetheless give you an opportunity to come up with a rough order of play, based on which items are likely to be long lead, need saving up for or, of course, need something else doing first.

I stuck it all on a spreadsheet, which makes it easy to add the bits I forgot and indulge in the unmitigated pleasure of ticking things off when they’re done.
For those who are sad enough to be interested, here’s the logic behind my particular approach. It may or may not work for you, but that’s your decision.

Stripping the top end of the engine may seem like a very odd place to start, but there is logic to it.
Firstly, it allows me to assess the state of the cylinder bore. This is important because knowing whether I need to have it re-bored (one of the few jobs I can’t sensibly do myself) and by how much, will determine which piston I need to buy.
I’ve already decided to fit the high compression SS90 piston, but do I want it standard, or oversize and by how much? Once I know that I can buy the piston and once I have that I can send it off to get the re-bore.
Incidentally, if someone says they don’t need the piston to do the re-bore, go somewhere else. A proper job involves machining to precisely the right piston clearance, not just an arbitrary plus 20, or whatever.

The other thing I can check is the big end wear. Alas, on the B40, a crankshaft rebuild is another one of the few jobs I can’t do. The crank is a press fit job and the combination of extreme force (typically seven tonnes or so) and precision needed to dismantle and re-assemble it requires a big hydraulic press and a lot of skill. Not to mention the fine art of truing and balancing it, so it’s a job for the professionals. That’s professional engineers, not smoothly dressed gentlemen with hot 1970s Fords and guns. I used to really enjoy that show.
However, dragging the ageing mind back to the matter in hand, it’ll make a big difference to the cost too. Quite apart from the cost of the crank rebuild, I may well then be tempted to fit a needle roller big end in place of the original plain bearing.
I’m not sure on that one. On the one hand, Jeff Smith got to second in the world championships on plain bearings and this will be a relatively low stress, low mileage road bike, on the other, I’ve no idea how often his engine was rebuilt and I want this bike to comfortably out last me. More thought required.

Having stripped the top end, reason dictates that I continue the engine strip. Again, there is logic. A very major factor here is clearing the bench space. I have only one small bench and as long as there’s half an engine sat on it I can’t use it for anything else. It’ll also give me a fair idea of what else I need to buy for it. B40 bits (especially tuning parts) are not always easy to come by, so having a shopping list to hand aids regular browsing of the web, autojumbles and any passing fellow enthusiasts. All of these will probably need to be enlisted at some point.
As an interesting (well, to me anyway) aside, it seems far easier to get BSA parts in the USA than it does here. I’m really not sure why, but beware import duty and the (sometimes higher) “administration fee” that the post office put on collecting it, when calculating prices.

Once the engine is safely packed away in bags and boxes (more on that later) I shall turn my attention to the front wheel, the reason for this is that I have managed to acquire a seven inch twin leading shoe brake which, while not correct for the Enduro or Trials spec’, is much a much better stopper than the SLS original.

According to the all-knowing RR (Rupert Ratio aka Dave Smith) it will fit in a B40, but may need some material removing to avoid interference with the fork leg. Since that’s all RR said on the matter, I have no idea how much or from where, so quickly fitting it, while I still have the forks assembled will enable me to quantify the job, or come up with plan B if it doesn’t work.

Sticking with the theme of long lead items, wheels come next.
The front will definitely require a new rim, since I’ve decided to fit a 21” in place of the original 18”. The enduro actually had a 20” front wheel, but good tyres in that size are few and far between, so most restorers opt for either a 19” or 21”. I’ll go into the reasons for my choice when I get to wheel building.

I’m not too sure of the condition of the rear rim, but the fact that it’s been painted over doesn’t lead me to suspect that it’s pristine. I’ll probably want to replace the spokes with stainless ones anyway and I’ll certainly have to dismantle it to refurb the hub, so that needs to come apart as well. Then I can order rim(s) and spokes.

Once those few bits are out of the way the strip of the cycle parts should be pretty straight forward.

I’ll need to check the state of the swinging arm bushes early, as this is the other job that I can’t do. It requires putting the whole frame in a big press to either remove or fit the swinging arm pin. My impression riding the bike home when I bought it (about 50 miles) was that it was actually in pretty fine fettle, the handling felt surprisingly tight and stable, but it needs to be checked properly. Casting about on the web I was surprised to find that leaving it in doesn’t seem to provide any barrier to cleaning or painting the frame. Indeed quite a few people have had the frame powder coated with the swinging arm in place. I’d have expected the heat/grease to cause some problems.

Storage
It has probably not escaped the notice of the more astute reader that I will rapidly end up with a large pile of bits, which need to be stored carefully and somewhere near sensibly, for a period of at least twice the estimated duration of the build!

In my case this is exacerbated by the fact that I don’t have a nice, dry, heated garage. Indeed, I’m still building in a tent. It’s a bigger tent than it was in the days of Little Suzi, but still a tent, I did invest in a tiny shed (3x4ft) for storage.

My suggestion of the basic requirements, when dismantling are as follows:-

Large and small Freezer Bags – the ziplock type work best and can accommodate parts up to cylinder head size.

Sharpie Marker – For writing on the freezer bags. You will definitely forget what some bits are (or which versions , if you’ve bought used replacements) and it’s really helpful to write on what sort of order they assemble in i.e. where spacers go and such.

Takeaway boxes – For small parts, or groups of small parts, cylinder head fastenings for example. One can of course buy lots of takeaways, but if you don’t want to risk your health, fifty new ones is only a few quid on the internet.

Big plastic storage boxes – the stacking type are good. Cheap from places like Willco and QD. You can put the freezer bags and takeaway boxes in them.

Mobile phone – PHOTOGRAPH EVERYTHING before you take it off. Digital photography is wonderfully free, so don’t skimp. Back up your pictures in the cloud (also free) and you have a secure record of what went where.

Vacuum cleaner – With a bit of imagination and some gaffer tape, you can suck the air out of the freezer bags and effectively vacuum pack your bits to stave off oxidation.

Silica gel packs – also available cheaply on the web. Stuff them in your freezer bags to keep the moisture at bay.

Tie on labels – old fashioned, but still the best way to label some parts.

All that may sound a bit anal, but it’ll add about twenty quid to your rebuild cost (unless you buy a vacuum cleaner specifically for the purpose) and could save you hours of work, and possibly some expensive bits, later on. In the words of the great Eric Burden (obscure 1967 song reference, just humour me) “it will be worth it”

Clean or grubby?
Personally, I prefer to clean off the very worst of the muck, just to make them easier to handle, but leave the parts pretty much as they came off the bike until I need them.
At build time it’s nice to pull out lots of clean and shiny bits, but clean parts are a lot less stable than mucky parts, by which I mean that newly cleaned surfaces are open to oxidation and scuffing, far more than those protected by a layer of grime.

To take this to it’s logical conclusion, try cleaning a cast iron part. I boiled my barrel (is it just me or does that sound like a Glaswegian insult.. “g’away and boil yer barrel, pal”) in caustic soda and it, literally, rusted faster than I could paint it.

The counter argument is that it’s not until a part is cleaned that one can properly assess its condition and consequently, whether a replacement needs to be sourced.

I suggest use of that wonderful oxymoron “common sense”. The barrel, for example, had to be measured accurately to resolve the rebore question, so that had to be cleaned straight away. The cylinder head isn’t going to be attacked straight away, so that can stay grubby for now.

Just remember that if you do clean something, figure out how you’re going to protect it first. In the case of the barrel, Granvilles cylinder black on the outside, WD40 on the bore and gasket faces and vacuum packed with silica gel.

BSA B40 Rebuild. What and Why – Restoration, Rebuild or Reboot?

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It’s surprisingly easy, in any project, to lose track of exactly what you’re doing and why. In industry it’s called “scope creep”, can cost millions and is controlled by having a tightly written specification and referring back to it at regular intervals, so that any change must be justified.

In bike building terms it’s a bit simpler, but it’s still a good idea to at least have a decent mental picture of your original objective.

When developing said picture one would be well advised to be both honest and unembarrassed. The latter is a lot to do with remembering that it’s your bike and you can do what you want with it. Someone somewhere will probably disapprove, but that’s their problem, not yours.

By way of explanation, here’s my logic.

I want an enduro style road bike. In all honesty, it probably won’t do the bit of green laning that we all say it will, since I already have a trials bike. It really is just a style/fun thing.

It won’t be my daily commuter, so it will probably be fairly low mileage and it’s unlikely to be thrashed.

I want something middle weight, to me that’s about 350cc.

I want another British bike, rather than a rice burner. Just because I like them.

It must be a practical ride on modern roads.
Now this is a potentially contentious one. I’ve read many an article by people who insist that their bog standard classic Brit is perfectly practical and I think they’re wrong. I say this, not as someone who thinks of brit bikes as some sort of ancient novelty and was brought up on Hondas. My first bike was a C15, followed by a 500 Ariel single. But that was forty something years ago and the roads were very different.

Sure, old bikes are fine for a Sunday run in the country with a few mates on similar bikes and in all honesty, this isn’t intended as a daily commuter, but I still don’t want to think twice about going anywhere on it. So here are my requirements for modern roads, and why.

Mirrors and indicators – Sorry, but the sheer volume of traffic nowadays means you need mirrors. Obviously anachronistic as they may be if you look behind you often enough to keep track of modern traffic, you’re not looking forward enough.

Nobody is looking for hand signals nowadays and, ugly as indicators may look, trying to signal right while your speed decays on a busy dual carriageway, just ain’t safe.

It must not be embarrassed on the motorway – I don’t intend to do a whole lot of motorway cruising on it, but you only have to get two miles outside any given town and you’re likely to be on at least a hefty dual carriageway. Even on A and B roads the traffic moves a lot faster than it did in 1962.

So the B40 is going to need a bit more power. I’m not talking about tuning it to death or trying to blow off anybody’s Kawazoomie, but a bit more would be good.

It must have decent lights – that means they must illuminate more than the front mudguard.

The brakes must have a significant effect on the speed of the bike – again, modern traffic moves a lot faster than it did forty years ago and drivers expect you to be able to stop, so they won’t allow you extra space to scrape off your speed with the soles of your boots.

It must go when I want it to – yes, old bikes will always need more maintenance than modern ones, but I don’t want to have to fiddle it into life every time I go out on it.

So that’s the requirements. How am I going to meet them with a B40?

On the styling side, I’m going to rebuild it as somewhere between the Enduro Star and the C15T (trials). Actually the Enduro Star didn’t exist until a couple of years after mine was built (and had a different frame) but the high compression piston and slightly hotter cam (used on the Enduro Star and SS90) will give it the gentle power boost that I’m looking for.

The C15T was made at the same time and had the same styling but was a 250. Both had a wide ratio gearbox that wasn’t too great for pure road use, so it’ll retain the stock gears.

So you can think of the result as an “in the style of enduro”.

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The Enduro Star

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The C15T

There are some out there who will consider this a terrible waste of a standard bike, and it’s a fair point. As it happens, standard B40s are still pretty common and I always hated the styling.

As I already mentioned, my first bike was a C15, which looked identical to the B40. At the time it was just an old bike and what I really wanted was a Bonnie café racer. Try as I might, I could never get the C15 to look like anything but the type of bike that peoples dads went fishing on and that feeling has stuck with me through the years.

Of course, the purists will tell me to go and buy an Enduro Star. Alas they’re usually kept on the shelf between the hens teeth and the rocking horse poo, a fact which is firmly reflected in the price.

Strangely, nobody seems to complain when people take standard Ford Escorts and build Mexico copies, or even rebuild A65s as Rocket Gold Star copies for that matter. Each to his own and all that.

So, the power part is pretty much taken care of by the SS90 piston and camshaft. It’ll also get a little bit of extra boost (along with improved starting and reliability) by the addition of electronic ignition and a modern carburettor. The former being completely invisible and the latter pretty discrete.
12v electrics and a low power/high output LED headlight bulb take care of illumination, again pretty much invisible until you switch the lights on.

Braking needs a bit of compromise. I suppose one could fit modern forks and a disk brake (enough of the “pre65” trials community seem to want to) but, frankly, that would be losing quite a lot of its fundamental B40ness. I’m planning to fit a ’67 twin leading shoe brake, doing a proper job of arcing the linings and using some of the clever modern lining materials. That should be enough to cope.

All that covers one area of the project specification. The other two factors are time and cost.
Time is pretty fluid. I don’t have, anything that could be described as a deadline, though I do get terribly impatient when a new project is on the go and I have got an urge to do a 1200 mile bike rally in July this year, so now I’m in a hurry already..

Cost is a different matter. I’ve got a sort of a budget in mind, but it’s not set in stone. Unlike Little Suzi, this is not intended to be a shoe string job, so I’ll invest enough to do the job right. At the other end of the scale it’s not a money no object job either.

To try and make some sort of sense of that, bits that need replacing will be replaced. All the simple bushes and bearings will get done, but some of the most expensive stuff will only be done if needs to be. Parts will be picked to be fit for purpose. No cheap rubbish, but not necessarily the Rolls Royce option either. I’m not going to spend a fortune building a full race engine for a genteel road bike, or leave knackered old shocks in it to save a couple of quid. Back to that common sense stuff, really.

The Backyard Builder’s Back with a BSA B40

What-Ho, readers old and new. Well, the clue is in the title really. Speaking of which, my apologies to people suffering from Bells Palsy and Rowan Atkinson impersonators. Or Rowan Atkinson, I suppose.
Anyway, I’m back, with a new project.  Actually there have been a few in between.  There was the  SV650/Minitwin  track day bike, that convinced me I would never be a racer.  There was starting out in trials, which convinced me just how unfit I am, then the switch to the much more serene and safe world of pre ’65 trials (on a lovely little Cub) and the consequent shoulder injury that I’m still recovering from six months later.  Not to mention the road bikes of course. So I won’t.

However, to the point.  I recently became the proud owner of a 1962 BSA B40 (350 single, basically an over inflated C15) in running order, with a week and a half’s MOT left on it and, slightly bizarrely, a 1964 age related registration, despite what look like matching frame and engine numbers.
I say running order, it did actually run and handle, quite nicely.  The brakes were a bit scary (or have I just got used to modern ones) and when I stopped half way home it did produce a sizeable cloud of smoke/oil mist.  But I’m pretty sure that was just because the cover for the hole to access the clutch cable was missing.
Any BSA historians out there may well have just thought “hang on, the ’62 B40 didn’t have a hole to access the clutch cable” and, in truth, neither did the C15 from which the outer timing cover that was fitted to it was nicked…    until somebody hacked one out of it.
To be fair that (though true) probably casts it in a bad light.  It’s actually a pretty good (if not pretty) little bike.
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And I have plans for it!  As ever, some will hate them and some may even love them, but the process  (despite the feedback suggesting title changes such as “Boring old Pillock” (which doesn’t even alliterate) or “Bodging B*stard”  (with which it’s hard to argue) will be documented and explained here.
Having said that, I lay no claim to knowledge, expertise, skill or wisdom in matters motorcycle, so take my scribblings as they stand and keep the salt handy.

For those who remember Little Suzi, my operating conditions have improved greatly.   I now have a  bigger tent!

 

Pride, Prejudice and Excess

Now here’s an interesting question, well, to me anyway.  I had occaision, only today, to wander around a very large motorcycle shop. There was much fine and shiny stuff there, most of which left me fairly ambivalent to be honest, though I did come dangerously close to parting with real money for a rather beautiful ZZR1400. Not normally my style at all, but the whole thing was so well proportioned it just fit right. Even my long suffering girlfriend had to agree (not without a measure of enthusiasm) that it was simply made for me.
OK, so it is insanely fast and surely would require a gentle touch in the wet but, as my old mate, who retired from racing (still competitive, but broke) at the age of sixty seven, always pointed out, “the throttle works both ways”.

So firstly, should it be embarassing to ride the worlds fastest production motorcycle and only take it over the ton once a year on a European run? How many people with such bikes really use the potential? How many people get anywhere near the potential of any bike over 600cc on the way to work anyway? I did know one such chap, but I’ve long lost count of his list of broken bones.
For me that’s an easy one, if I happen to like the bike and don’t get frightened by the power output then who should care? It’s my bike (well, I’d like it to be) and I’ll ride it how I want to as long as that doesn’t endanger anyone else.  What I liked about the bike was the feel of the thing.
To be brutally honest, I neither knew nor cared that it was that fast at the time.

Yet I’m guilty of the self  same judgement. I was looking at a rather smart KTM recently, noticed that it had chicken strips even wider than mine on the tyres and thought, “so why buy such a sporty bike then?”…  because he wants to, of course, and what’s wrong with that?

But that led to the next question. Not very far from it was a very bonny CBR1000 in full Repsol replica livery.  Without doubt a slower  machine, but I reckon that I would feel embarassed riding it.
There’s absolutely nothing wrong with it. It’s a very pretty bike, nobody’s pretending that it’s a MotoGP bike and it’s flying the Honda flag. But surely, riding it in an old jacket and a pair of jeans (armoured or otherwise) or even in a set of plain black leathers would look all wrong.
In fact, riding it in anything but a set of Repsol replica leathers would look wrong. And then I really would look like I was trying to be Mark Marquez, which at well over twice his age and and far too close to twice his weight would look just plain sad.

So where do we get our prejudices? What’s the difference between a set of replica leathers and going to the pub in your teams football shirt which, come to think of it, I wouldn’t dream of doing either, even if I had the slightest interest in football.  But thousands of others do and quite reasonably don’t expect some pillock to point out that, since they’re clearly out of breath carrying a round from the bar to thier table, they may not be truly qualified to wear the uniform of elite athletes.
And now I’ve strayed into really scary territory. Uniforms!
You see, despite having had long hair from the age of twelve, telling the Boy Scouts to take their para-military orders and shove them after one day, being threatened with expulsion from school for starting the UKs first secondary school chapter of the NUS, and even briefly living the hippy dream in a commune (well, it was a commune, but it was also in Middlesbrough…  and I had a job… but it was a commune)  I was also brought up on “The Cruel Sea”, “One of our Aircraft is Missing” and tales of Douglas Bader (who it turns out seems to have been something of a bad egg and stole kills from his underlings) so there’s still something very deeply ingrained that says you can’t wear the uniform unless you’ve earned the right to do so.
Now that, is a lot more scary than trying to put 185 horsepower down through a single, cold, wet tyre!

 

Tyre Change

It was strange to realise that after some forty years of motorcycling (Ouch! Can I really be that old?) I had never changed a tyre.
The front was a pretty new Conti, but the rear was definitely due for replacement. A quick search on the web showed a massive price range, with something called a CST/Maxxis coming out cheapest. In my blissful ignorance I assumed that CST was the manufacturer and Maxxis the “model”, so I did a quick web search to see what I could find. The results were fascinating.

“RANT ALERT”
Every time I looked up CST I found posts saying things like “ I wouldn’t trust cheap Chinese tyres, they’re all made of monkey poo/cheese/inferior plastics etc. “ then when I looked up Maxxis I found lots of posts saying “they work great on my Hyabusa”, “I prefer them to the Bridgestomes I used to run” and similar positive comments. It seems they do wear a bit quicker than more expensive tyres, but that’s not too much of an issue with a GN. Then I finally found one post, from someone who works for Maxxis, which pointed out that “CST and Maxxis are the same tyres, they just changed the name for the American market!”
I had the same thing when I looked up the big bore kit. Lots of posts saying “I wouldn’t trust cheap Chinese crap” and then three from people who’d actually fitted them and said that they’d had many trouble free miles and were perfectly happy. The point is that virtually all the negative posts I see about Chinese kit (and they are far and away in the majority) are from people who’ve never tried the products. Is this a form of technical racism? I have had a couple of really nasty Chinese barbeques and I have an extremely good Chinese studio microphone, which became my firm favourite over many at anything up to ten times the price.
I would simply say that if you’re going to slag something off, do it from a position of knowledge, or you may just look a bit like a right plonker.
As final comment on the matter, I have now put 5500 miles on said Maxxis tyre, find it very nice to ride on, the only grip problem I’ve ever had was when it was completely unloaded under heavy braking (alas, the only tyres that work when airborne seem to be reserved for that young Marquez gentleman) and it’s hardly worn at all.
I certainly wouldn’t describe myself as particularly timid rider, yes, I have the usual 15mm chicken strips, but I do actually use the tyres with reasonable abandon.
In short, I rate it as a really good tyre.  I confess that it would take a lot to get me away from Bridgestone on the ST1100, but that’s a wholly different application and puts down five times the power.
“RANT OVER”
So, back to the plot. The first thing to do was the inevitable internet search for you tubes on changing tyres. I was quite disappointed for a while. The first ones I found said “start off like this…” then cut to a point just after the really difficult bit and continued. Another one was billed as “How to change a motorcycle tyre” but started with the guy saying that he’d never done it before and went on to show him wrestling with the thing on the lawn for a few minutes before cutting to “and I finally got the thing off”. Patience was eventually rewarded and I found one youtube which told me the bit that I needed to know.
I can’t find the tube again now, but the crux of the matter is where to put the second tyre lever and the trick is to place it where the bead of the tyre is just below the rim, about three inches from the first one. Any nearer to the first one and it doesn’t do much, any further away and it’s too hard to pull over. It’s a simple thing, but a real pain if you don’t know it.

Clean Wheel Mucky Wheel

So, with the wheel reasonably well cleaned (I confess that I didn’t have the patience to do a fantastic job on all the spokes) and the new tyre on it was looking pretty reasonable, at least from twenty feet away, and it was time to reassemble the bike…

GN250 Cafe racer right GN250 cafe racer left

…and dark.

Polishing Aluminium

 

Before and after

This is something which I’ve got steadily better and braver at over the course of the build and running of little Suzi. I have yet to figure out exactly why one can buy a brand new bench grinder for £20, yet it costs £60 for a polisher, but unsurprisingly the result is that I haven’t got one. I did try a sisal wheel in an electric drill and it seemed to have little or no effect whichever compound I used, so that was clearly for something much nearer to finished.

In the end I came upon a very simple process that doesn’t take anywhere near as long as one would imagine it does.
Now, the big problem with polishing ally bits is that you must first destroy whatever finish is on there. You get used to it after a while, but for the first few cherished items you refinish there will come a point where you make loud reference to some sort of bodily function (be it digestive or reproductive) the general gist of which will be “It’s Ruined!”
It helps to remember the blindingly obvious. One cannot fill up a scratch by polishing. That means that the only way to polish out a scratch is to scrape off the rest of the finish, down to the level of the bottom of it. The only way to do that effectively is with some sort of coarse abrasive, which leaves the whole shebang a mass of ugly scratches.  Courage mon brave!  repeating the process with successively finer abrasives will bring it back better than before…   eventually.

It’s also worth remembering to tailor your aproach depending what you’re doing.  The Suzuki fork legs were very much built to cost. Most of the front was a fairly good brushed finish, most of the back was a bit coarser and all the bits that either don’t show or are difficult to get at were left rough cast.
Since I was working on a cheap 1990’s commuter, I was delighted to take the whole lot down to something nice and shiny, removing casting marks and part numbers as I went.
Do that to George Brough’s personal prototype racer and you’ll probably be wiping tens of thousands of pounds off the value, so think before scrubbing!

While on the subject of “overpolishing” be very careful around dust and oil seals. It’s almost impossible to polish to a sharp edge without rounding it off a bit, which could affect the function of things, especially the fit of rubber seals. Either stop a bit short, or mask the very edge to keep them sharp.

I started with 400 grit wet and dry (very wet, with a splash of fairy liquid in the water) then 800, then 1200 then (and this is when it starts to look really good) a Brillo pad. The Brillo pad makes a hell of a mess with all the soap, but it does bring up a nice shine. Then finally wash and dry it and go over with a J cloth and Solvol. The final stage is a bit disappointing at first, because the Solvol leaves a dull grey deposit, but once washed off you will be proud of the result. How good a finish you get is really down to time, patience and what you can be bothered to do.
If you go to the length of taking out deep scratches and dings, then you’re going to have to start with something really aggressive (much later when I did  the front forks I started with a Black and Decker Mouse sander and 180 grit) but then you’re making a lot of work getting back to a shiny finish.  I eventually found some fantastic 3M sanding pads at a car boot sale. They’re on a firm foam background about a quarter of an inch thick and come in grits from 400 to 1200 and most points in between. They don’t fall apart when wet and are really easy to use. For this round I opted to retain a certain degree of “patina” and remind myself of the twenty foot rule.  If you don’t know what the twenty foot rule is then you clearly haven’t carefully read the whole of this blog, which is absolutely fine by me… but I’m still going to be mean and not tell you, just because I can.

Keeping any sort of shine on ally bits is something that’s debated to death in many, many different forums. There are a couple of treatments (I seem to remember Zoop being one) which are alleged to be very good, but are quite expensive. A coat of clear lacquer can produce fairly good results, but will yellow and peel, isn’t quite as shiny and won’t work on hot bits. Or you can just polish the thing on a regular basis. I’m no nearer to the answer than anyone else. I tried lacquer on the rear brake plate, but it looked manky, so I gave it a coat of wax. On the other hand lacquer looked fine on the brake and gear levers  (different alloy) so it becomes a sort of pick and mix arrangement.