Thursday, 30 September 2010

Message to the guy who asked about the Nexus yesterday

To the guy with the ginger hair, beard and black dropbars in Manchester yesterday. Nice chatting to you. Sorry I didn’t get chance to direct you to this blog, hopefully you’ll come across it anyway. To answer your question, the Nexus hub is great. Very smooth, free running and almost totally silent. You have to learn a different style of shifting compared to a derailleur, but it’s very simple and actually more user-friendly (it helps to ease off slightly when upshifting and be wary of the change between 4th and 5th). The range of 307% is more than enough for commuting 20 miles a day.

Mine is the sg-8r31 model. The latest one available is sg-8r36. Nearly all of the complaints you might come across on the internet will be about the earlier models such as sg-8r20. I presume from the experience of my hub that shimano have ironed out the problems with the revised models. Presumably the very latest models and the premium redband model or Alfines are even better than mine.
I intend to do a proper review at some point in the future, but for now, based on ‘fit and forget’-ability so far I’d give it 9/10.

Tuesday, 28 September 2010

Bike kit

This is the simple set of tools that live somewhere in the bottom of my pannier bag.

  1. Punture repair kit (with tyre levers inside)
  2. Crappy Muiltispanner
  3. Decathlon multitool
  4. Real spanner
  5. Mini pump 
Plus I keep an old sock tied to the seatpost, which is just for using as a rag if I ever need to touch the chain when out on the bike.

That's it. It's not much stuff and doesn't weigh much or take up much room. Obviously the main reason to carry this stuff is incase I get a puncture and need to do a roadside repair. But since March 09 when I started commuting everyday by bike I haven't had a single puncture to repair*, so this kit hasn't been a whole lot of use really but one day it might be the difference between a very bad day or just a slight inconvenience.

You have to hope that more people will steadily begin to commute by bike, but I can imagine something as simple as a puncture putting people off, so my tips would be:

  • Keep your tyres inflated fully - you are talking 50 psi+ even for cheap mountain bike tyres - much higher for skinny road tyres or small wheelers.
  • Carry a simple kit of tools like above.
  • If you're not prepared to do that - at least get a set of puncture resistant tyres such as Schwalbe Marathons. 
  • Stay out of the gutter - not just because it will encourage drivers to blast past you without a care but also because thats where all the glass and nails collect.
  • Don't go hopping on and off kerbs all of a piece - it pinches the tubes and twists rim tape.
  • Keep an eye on your tyres - give your tyres a once over every so often to check for any cuts or shards. - letting the air out temporarily will allow you to squeeze the tyre to reveal any nicks or shards embeddded in the rubber.
  • People also tends to get a number of punctures all at once. Probably because they've repaired the tube but not examined the tyre to make sure whatever caused the puncture in the first place isnt still embedded, waiting to cause another.

I had this post all ready and lined up for posting when suprise suprise, I get off the bike at home to the sound of 'pssssssssssttttttttttttttttttttttttttt'. Puncture. Sods law strikes again. Anyway, at least it was at home and not halfway through the journey. So I'll be taking my own advice and replacing the Cityjets on the Nexus with a pair of Marathons as I'd orginally intended. 

Here's the bugger. A tiny shard of brown glass (do they even make brown glass anymore?, where the hell did that come from)

Monday, 27 September 2010

Hopper hubs (pt 4)

This is the hub that is going be laced into the rear wheel for the Hopper. It’s a Steelite SAB 3 speed Sturmey Archer with a 70mm drum brake from 1994. I got it for £8 posted. Why so cheap?, well it’s because the axle has snapped in two.  The rest of the components are fine (missing a few ball bearings though), so with a new axle fitted it should be a fully working 3 speed braked hub for roughly half the price that a fully working one would cost second hand off ebay and about a quarter of the price of a new SAB hub. Plus, in the process I get to have fun stripping it down and fixing it.

This is a greased hub rather than an oil lubricated hub. Apart from the changes related to lubrication (i.e. sealing/ball races) the most obvious difference between this hub and the AW that came fitted to the Hopper is the width of the 3 speed internal mechanism. With this hub the internals have been shrunk down a bit to accommodate the width of the drum brake without making the hub shell too wide.

The trickiest bit of opening up these hubs can be unscrewing the Ball Ring. This needs either a special Sturmey Archer 'C' Spanner or a hammer and punch to get it loosened up. Normally it should be fairly easy to undo with a couple of taps, but this one was very stuck. Probably a side effect of this being a powder coated hub. It took some serious welly from a hammer and chisel to get it free. I ziptied the brake to keep it locked in the hub so that I wouldn't damage the thin lip near the spoke flange when it was in the vice.

You can see from this photo that the hub shell is wider.

Whilst in this photo you can see the internals are more compact. These two aspects together provide the room for the drum brake.

These hubs are very easy to strip down and shouldn’t be intimidating to anyone who fancies having a go. I would do a write up of stripping a standard AW hub, but there is no point when I can just direct you to this youtube video which covers almost everything.

One thing to remember when playing with these hubs though is the pawl springs. They are tiny. If you aren’t careful you could tip up part of the internals, a pawl pin can drop out and the pawl spring will vanish from the face of the earth. So it’s a good idea to put an elastic band around the pawls whilst you are working, just in case.

Here’s the disassembled hub. You could strip it down more than this, right down to every single individual part but this is enough for me to get it fixed and re-greased.

The original axle is a HSA534. You can't buy these, so you could be forgiven for thinking this hub is not repairable. But the reason you can't buy them is they have been superceded by a better design. This better axle is the HSA571, which is available quite easily. On the old axle the Sun Pinion is a seperately machined piece which has been stamped permanently onto the axle - this creates an inherent weak point and is the reason this axle has somehow gotten snapped. The newer HSA571 axle is machined from a single piece, problem solved. In this photo I've removed the small circlip from the old axle, ready to put it on the new one - it holds the Planet Cage assembly in place.

I couldn't find out what grease you are supposed to use in these hubs, or anywhere obvious which sold the actual Sturmey Archer grease. So I got a tube of Shimano internal hub gear grease. If it works in more complicated 7/8 speed Nexus hubs then I figure it will work ok in a simple 3 speed. the hub was making all the right noises when it was greased and back together, so it should be fine.

Here is the hub all cleaned up and rebuilt with brand new outer parts such as wheel nuts, indicator chain, brake cable parts and brake arm clip. It's now all ready for lacing into a wheel and testing out. The front wheel will get a standard X-FD drum brake. Happy days :)

You can find the Technical spec in PDF form on Tony Hadland's excellent site, which is essential for finding out the parts numbers. As with all these things though, you can only learn so much by looking at the exploded diagram, best to take it to bits and find out for yourself.

Friday, 24 September 2010


Part of my normal morning route is in semi lockdown today due to the imminent arrival of some members of  the Pathological Liars Society. Peter St and a few surrounding side streets are all closed to motorists meaning me, a few other cyclists and plenty of pedestrians got a very rare chance to experience a main city centre road without the bull in the china shop.

There’s a lot of barriers and checkpoints been setup on the various side streets, but nothing is manned or in operation yet. A few vehicles were getting access, but otherwise the roads are empty.

Interesting how the instant the road is clear, pedestrians begin walking around a 4 lane road without a care, cyclists lean back and relax & I stop in the middle of the road to take pictures. There isn’t even any thinking time, nature just takes over and suddenly that busy horrible city centre road has become a pleasant environment and you can see that  the 20 odd metre wide space is actually enormous and we are all getting seriously short changed.

The closure has had a knock on effect on Deansgate, meaning that was a bit less busy as well. I don't see why these roads at the very centre of the city need to be anything more than access only - like the auto bollard controlled areas at the bottom of Market St & M&S. Pipe dreams I know, but it would transform Manchester, just as it has transformed the area around M&S.

I love how these photos bring up other things that you never noticed at the time. People's adversity to rain shows no bounds. It wasn't raining whatsoever, but this gent was happily strolling to work with his brolly up. Even more odd when you consider how windy it is this morning.

In other news: They are filming the new Captain America film on and around Dale St in the Northern Quarter. I took a couple of snaps myself at dinner, but you are best just looking at captainamericafilmingmanchester  to see what's going on.

It seems all these motorists failed to read the various signs posted around the city in recent weeks warning of delays during the conference, so they drove anyway. Note all the lights are on green, but nobody is moving an inch. Doesn't stop everyone from parping their horns at eachother - because that always solves the congestion, doesn't it.

Compare this shot with the ones above, neither are a problem for me on the bike, infact if cars have to be on the road I'd prefer them in this state but which one looks most pleasant?

Thursday, 23 September 2010

Did it rain last night?

This bit of path has always got puddles on it, but this time they were BIGGER!. It's actually alot of fun weaving through the smaller puddles, then slowly cruising through the edge of the bigger ones. They aren't too deep, just wide. This is another joy of having a comfy everyday bike like the Nexus, it can virtually go anywhere in any weather.

Hmmmm....a post about some puddles.....just realised how boring that is, sorry :-)

Tuesday, 21 September 2010


My bike doesn't have insurance, or VED (the fabled road tax) and it hasn't passed it's MOT (because it's never had one). Which is a bit like this white van man on Deansgate yesterday. Pulled over by a couple of ANPR police cars. The thing looked like a wreck and I suspect they didn't need the fancy gizmos to recognise that it would be worth their while to pull it over.

Driver and passenger were gone (driver presumably in the back of one of the police cars) when I passed again later. So it will have been confiscated and crushed with any luck.

If you look closely you might be able to see the two little black boxes just above the rear spoiler on the police car. These are the cameras for the ANPR 

Monday, 20 September 2010

Shopping trip

Inspired by Mr.C who in turn was inspired by Urban Simplicity I thought I'd record my quick food trip. Since it's closest I went to Aldi in Hyde. Actually Morrisons is probably closer but I hate big busy supermarkets, on a week night Aldi/Lidl are nice and quiet so you can be in and out with everything you need in 20 mins without all the elbow barging.

On the way I cacked my pants when a group of 10 or so girls on their horses decided to have a full out sprint up the path that leads to Mill Lane just as I'm coming around the corner. This spot is a favourite for chavs on quads though, so I'll take the stampeding horseybirds over the 'innit' crew any day.

I managed to estimate how much would fit in the panniers and on the rack fairly well. It was mostly stuff to make packed lunchs and a few meals. The most important item being apple & plum strudel - yum.

There are at least some actual cycle racks at Aldi, unlike Lidl in Denton which seems to have nothing at all. Even here though you can see in the photo that the massive collection of trolleys get full cover from the rain, whereas the 3 cycle racks are languishing off to the side. **mini rant** - small stores like Aldi don't ever need this many trolleys!, why not have a few less and put the cycle racks under cover. Sigh. On a lighter note, if find you've forgotten a pound coin for the trolley, a 20p and a 1p on top of each eachother also works ;-)

Note the children's hoops (cereal) are not for children, they are for me. Damn good they are as well.


I should point out that my panniers are only small 25ltr front panniers. With big 40ltr ones you could easily carry more than this.

Saturday, 18 September 2010

Nexus Handlebars (Part 6)

This post is about the single best improvement I've made to a bicycle.

The vast majority of bikes available in the U.K. these days come with straight handlebars, or straight riser bars like the ones that came standard on the B’twin Vitamin (I'm ingoring dropbars as they are generally on a different kind of bike). Those are fine if you are going mountain biking on the Marin trail, but not so great if you are riding on the roads. Straight bars force you to lean forward on the bike, your centre of gravity is forward of your hips and you are taking a lot of your bodyweight through your wrists.

I had read a number of things about the benefits of an upright riding position, but a great post to read is this on Copenhagen Cyclechic which explains the benefits more eloquently that I ever could. After reading this last year I adjusted the position of the bars on my Trek to allow a more upright position and felt the benefit immediately. Equally it made me realize what it was that made the standard riding position of my M-bar Brompton so nice. However both of these bikes still left my hands in a straight position, 90 degrees away from the direction of travel. So on the Nexus I decided to do things properly and get a set of swept back handlebars like you would see on nearly every bike in Holland or Denmark. There are plenty of options out there and I had been eyeing up a set of North road bars from SJScycles until I found that Decathlon sell a standard set of swept back City Bars for £8.99.

Here are the new swept bars in a side by side comparison with the existing riser bars. You can see from this how much these bars alter your grip position. What isn’t clear from the photo is how much more freedom to refine the position is available with swept bars. With straight bars you are basically stuck with one fitting position, but the swept bars mean you can alter the angle of them ( or even flip them over) on the stem clamp and in turn quite dramatically alter the riding positions available to you. This brings up yet another drawback of the majority of bicycles available in the U.K. Many now come with a threadless stem, which offers far less adjustability than a quill stem or even an adjustable quill stem like is fitted to my Trek.

I knew from my own experience and reading that the swept bars would be an improvement, but wasn’t expecting the sheer difference it made to the experience of my commute. The Nexus is a much much faster bike with swept bars fitted, so much so that I found myself cruising in 8th gear quite easily even with the new higher gearing. The bike is more comfortable and my overall feeling of subjective safety is greatly improved by having my head raised higher and upright, giving a wider view of the road and better shoulder checking. Bumps and potholes are also much less jarring, as there is less weight over the front wheel and less impact coming through the wrists.

Here is another good post on the benefits of riding upright from Sheffield Cycle Chic which catches upon the fact that many cyclists subconciously want to sit upright on their bikes. Everyone wants a cool looking bike, be it with dropbars or straight, but if they could only see themselves cycling, they might notice that their own bodies are telling them to sit upright. The problem is their bikes don't let them.

Even now the riding position on this bike is not as upright as it could be, mainly because of the stem. So there is always the option for putting a taller shorter reach stem on as well.

Thursday, 16 September 2010

Fallowfield Loop 2

I decided to take a more scenic route home the other day so headed down Wilmslow Road to get to the Fallowfield Loop which would take me to Reddish Vale to get over the motorway and back towards Denton.

Since I forgot my camera when we visited the Fallowfield loop for the first time a few weeks ago I took the opportunity to snap a few photos of the route. I also came across a nice webpage that has plenty of photos of the railway line when its was in use, disuse and being built into the route it is today, worth a quick look. As is this page where I found out there is actually a tunnel underneath Sainsbury's on Wilmslow Road, the design was a cock-up though so it's not in use.

There were quite a few other cyclists making their way along, I just wish it was as busy as some of the bike paths we are all so envious of in Holland. A quick look at many posts on David Hembrows blog shows what rush hour on a bike path like this should be like.

I'm reliably informed by 'he who knows all' that the huge pipes crossing the loop on this trussed bridge are part of the Thirlmere Aqueduct. Most of the aqueduct is underground and doesn't appear on any internet maps, but you can trace the route on your A-Z of Manchester. It's one of those ridiculously big engineering feats that, sadly you just can't imagine us achieving today.

Most of the barriers on the Loop have a decent enough gap (although still a pain) for you to slow right down on the bike and navigate through without having to put a foot down too much, but for some reason this one had to be different. Bit annoying that.

Sneaky peek at part 6 of my Nexus build
It's lots of fun being able to cycle along with one hand on the bars, taking photos with the other when there's no cars, potholes, grids etc to worry about.

I came off the Loop for a short section of road to get down this road (National route 6) to get to Reddish Vale. (note to self camera in pocket with lens against leg causes misty lens syndrome)

Passing underneath the Railway line

This section is the only real bugger on the whole journey, it's perfectly rideable but crashing up the very lumpy track (photo below) might become a chore if it was day after day. On the other hand maybe the car-freeness of the rest of the route makes up for it. It's a compromise really, If I was on my old Mountain bike then this section would be the highlight of the route, but on the Nexus it's it'd be nicer to have a entire route of tarmac. It's fine though, I just trundled up it slowly in 1st gear.

Once you have made it up this track and over the motorway there's a short section of wide track then it's back onto residential streets and off to home. You can also carry on beside the River Tame to get over to Gee Cross/Hyde.

I enjoyed this ride so much I came back the same way the next morning, and each day after that (this was a week ago). It takes about 10 mins longer than going the direct route down Hyde Rd, but if I'm not in a rush I think this might become my regular route for a while.

Below is a rough map of the route. Blue is entirely seprate from motor traffic, orange is quiet roads and red is busy Wilmslow road, but it does have cycle lanes for the whole way along. For anyone who wants to start riding into Manchester from the Hyde/Denton area but is still put off by the amount of traffic on roads such as Hyde road I'd definately recommend this route as a fun starting point.

Tuesday, 14 September 2010

Nexus Gearing (Part 5)

As standard the B'twin Vitamin came with a 36 tooth front chainring. the Nexus hub I got off ebay had a 20 tooth sprocket fitted. Using Sheldon Brown's Internal Hub Gear Calculator I can see that this gave the bike a gain ratio range of 1.8 - 5.6 (or 24.4 -74.9 in gear inches) which felt too low for my legs, but good enough to put up with for the time being.

I had planned to fit a smaller rear sprocket to the Nexus hub inorder to raise the gearing. But there is a problem with the shimano gear shifting design that isn't apparent in other mechanisms such as the Sturmey Archer style shifter toggle. The Shimano system rotates around the axle and takes up quite a bit of room, this means that there is a minimum sprocket size that can be accomodated on the hub before you start getting issues with the chain fouling the shifter mechanism. The range of gears I wanted needed a 14 tooth sprocket, but the minimum size the hub can safely accomodate is 16 teeth.

So since that was a dead end I bought a new longer 1/8" chain and fitted an old 44 tooth front chain ring I had left over from when I raised the gearing on the Brompton.

Shimano recommend that you keep the gearing as close to a 2:1 ratio as possible. This is to do with the amount of torque being transferred through the hub and I won't pretend to understand it. But basically 44 divided by 20 equals 2:2 which is closer than some of the acceptable ratio examples that Shimano give in the Service Instructions so it will do just fine for me.

On square tapered cotterless cranks you'll find a bolt under a cap on the chainring like this:

Usually a normal wrench socket will be too thick to fit in here and undo this bolt, so you'll need a tool like this one that has very thin clearance allowing you to undo the bolt.

Once that's out you'll need yet another special tool called a crank puller. This screws into the crank and chain ring and allows you to use either an allen key or spanner to pull the crank away from the sqaure tapered axle.

With the old chainring removed you can fit the new one, making sure its on straight and also opposing the other crank arm at 180 degrees. Then use the bolt you removed earlier to tighten it onto the axle.

This bigger chainring means the chain has to be extended. I choose to simply add a few more links to the existing chain rather than fit an entire new chain. I test fitted the chain to see roughly how many new links were needed.

Then spliced in the new links. Mounting the chain splitter in a vice can make things alot easier.

And finally the finished upgrade.

I had planned to flog the 36T chainring on ebay but in clumsily removing the pedals I managed to break the plastic guard. This is why the blog is subtitled 'making, breaking and riding bikes in manchester' because if something is flimsy enough to be broken easily, I will inevitably break it at some point!.

The crank arms don't match anymore, but that doesn't matter, at least I've made use of something that was just sitting in a draw.

This set up now gives me a range of 2.2 - 6.8 (or 29.9 - 91.5 gear inches) which is just about right for setting off in 3rd and running up through the gears and cruising in around 6th or 7th. That leaves 1st and 2nd for going up steep hills and 8th for coming down them!.

Coincidentally 20T - 44T is also the right size for a Hebie Chainglider to fit....hmmmm.....

Monday, 13 September 2010

Burning Rubber

There was a fire at a tyre depot in Levenshulme overnight. Luckily I was taking a scenic route this morning rather than going through the Gorton area where it looked as if the smoke was blowing. The news report says the site holds 150,000 used car tyres - there's another reason we could all do with driving cars less.

A couple of Engine drivers were taking a break whilst they filled the tanks up from an outlet next to the entrance for the Fallowfield Loop.

On a sidenote, this is what happens when inconsiderate drivers dump their car at a junction so they can nip into the off licence. The bus driver had no chance of making the corner so had to reverse a couple of times to be able to squeeze through. Does make you wonder why they send such massive buses out on routes through tight residential streets though, its hardly packed with passengers is it.

Saturday, 11 September 2010

South Manchester Cycle Jumble Sale

I popped into the South Manchester Cycle Jumble sale last Saturday morning after finding out about it from a comment by LC on Manchester Cycling. It was a nice little setup and worth the visit. There was a decent range of stuff for sale, but mostly it seemed to be parts you might want if you were restoring a vintage racer of some sort. I had been hoping to find some swept back/north road handlebars, but as there weren't any I got some from Decathlon on the way back instead.

I however did buy a 700c from wheel for a tenner, which will at some point go towards converting the fixie I built back into something much less fashionable with gears, but potentially might actually get ridden for once.

Most of the bits and bobs on sale were run of the mill items I've seen before. Lots of AW hubs, drop bars, brake calipers etc, but this one bike demanded a photo to celebrate the computer worthy of Captain Dashboard. The earliest I can remember of cycle computers they looked pretty much the same as they do today, but with crappier rubber buttons and cheaper plastic casing. This thing is like a gameboy sellotaped to your bike....late 80's? I don't know. Nice to look at and photo, but I think I'll stick to my Sigma.

There was this speedy looking  tricycle parked up as well. However the need for a helmet when you are riding this thing confuses me somewhat.

All in all a nice little event to visit, especially if the bike you are building is missing those all important gold drop bar brake levers.