Search found 1779 matches

by robc02
3 Mar 2024, 8:15pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey archer anti rotation washers
Replies: 9
Views: 524

Re: Sturmey archer anti rotation washers

I can vouch for the fact that HMW494 can break easily - having had a spate of breakages a few years ago. Having said that, I am still using them (I had quite a few in stock) and haven't broken one for several years.

I am now always careful to see that they are fully in the dropout slot before tightening the wheel nut. I think I might previously have been letting the wheel nut force the washer into the slot - probably when replacing the wheel after fixing a puncture on cold wet commutes!
by robc02
13 Dec 2023, 4:06pm
Forum: Bikes & Bits – Technical section
Topic: Why are most bikes still derailleur?
Replies: 137
Views: 46007

Re: Why are most bikes still derailleur?

ThisWreckage wrote: 13 Dec 2023, 1:38pm
I'd like to know if other users of hub gears find the same.
I have a 1950s 4 speed hub geared roadster that is in regular use. Once set up the only maintenance it gets is an occasional squirt of oil through the lubricating cap. It has been like that for well over 10 years.
I also have a drop bar hub geared bike that is my usual commuter. My commute is 12 miles each way and is mainly on poorly maintained, muddy and gritty rural lanes so is very hard on transmissions. The bike has had Sturmey Archer 3 speed (AW) and 4 speed (FM) hubs at various times. Again, once set up the only maintenance they get is a squirt of oil, unless something else changes - such as moving the wheel to adjust the chain or to change an inner tube. In such cases, adjustment of the cable tension may be needed. I normally have to replace the chain and reverse or replace the cog at the end of each winter.
by robc02
29 Nov 2023, 4:28pm
Forum: Does anyone know … ?
Topic: Tyre choice for intermittent black ice?
Replies: 46
Views: 8547

Re: Tyre choice for intermittent black ice?

It probably depends on how intermittent the ice is.

For several years I had Schwalbe Marathon Winter studded tyres on a bike from about November until March. I only used it for my commute when it was cold enough to suspect icy patches. They worked well on those icy patches, but overall I felt they were overkill for my purposes.

I now have the same bike fitted with Continental Top Contact Winter in 42mm width and find them a better compromise. I wouldn't deliberately ride them on sheet ice but have found them OK on the patches that I usually encounter.
by robc02
22 Nov 2023, 11:49am
Forum: Bikes & Bits – Technical section
Topic: Tubeless tyres; what repair stuff do you carry?
Replies: 36
Views: 1935

Re: Tubeless tyres; what do repair stuff you carry?

Like Colin, I also get a lot of thorn punctures, though mine are on my commute through rural lanes and are frequently in the dark - so fixing punctures or changing tubes is a real hassle. Adopting a tubeless setup is an option I am considering, but I am concerned that if a puncture fails to seal and I have to fit an inner tube, it will immediately get punctured by one of the numerous thorns from previous punctures that have sealed successfully.
I wonder if others have experienced this and how they deal with it?
by robc02
25 Oct 2023, 3:55pm
Forum: Bikes & Bits – Technical section
Topic: Carbon forks with mudguard clearance.
Replies: 9
Views: 1488

Re: Carbon forks with mudguard clearance.

This one is currently unavailable but it might be worth contacting Spa to find out if they plan to get more:

https://www.spacycles.co.uk/m21b0s29p26 ... -Road-Fork

As noted above, it will probably raise the front a bit. Every 17mm height increase will slacken the frame angles by roughly one degree.
by robc02
3 Oct 2023, 8:56pm
Forum: Bikes & Bits – Technical section
Topic: AW3 and a hill.
Replies: 13
Views: 877

Re: AW3 and a hill.

Carlton green wrote: 2 Oct 2023, 8:29pm I do wonder whether the correct indicator rod has been used and using a four speed shifter is questionable. A gear of that age could be in any condition internally.
Providing everything else is in good condition a 4 speed shifter can be used with a 3 speed hub - just use the top three indexing positions. For a number of years SA produced shifters labelled 3 or 4 speed:

https://velobase.com/ViewComponent.aspx ... 5b65400f0c

I have used this arrangement myself with no problems.
by robc02
31 Jul 2023, 7:57pm
Forum: Bikes & Bits – Technical section
Topic: SA Dynohub - wiring stand light/LED
Replies: 20
Views: 1207

Re: SA Dynohub - wiring stand light/LED

Presumably the regulator that they show is rated so that it prevents too high a voltage damaging the capacitor. If so, then the capacitor should be OK either side of the switch - though for belt and braces it might be best on the LED side. The downside of this is that it will only charge when the switch is on so will slightly delay the lights reaching full brightness.

An alternative would be to connect a protective device e.g. a suitably rated zener, directly across the capacitor. Then it doesn't matter which side of the switch it is on.

A second alternative would be to do away with the switch and leave the lights permanently on. That way there is always a load on the dynamo so it will be less likely to produce an overvoltage. I would still protect the capacitor though.
by robc02
31 Jul 2023, 4:34pm
Forum: Bikes & Bits – Technical section
Topic: SA Dynohub - wiring stand light/LED
Replies: 20
Views: 1207

Re: SA Dynohub - wiring stand light/LED

If I've understood you correctly then yes:

1. Dynamo wires connect to bridge ac terminals and nowhere else. The SA hub doesn't have a connection to earth (i.e. the bike frame) so this shouldn't be a problem.

2. Bridge positive and negative can connect to the lights via your switch. The diagram doesn't show a switch but there is no reason you can't use one. Your two lights will be connected in parallel.

3. The capacitor connects across the bridge positive and negative wherever it is convenient - your switch is probably as good a place as any. Double check the capacitor polarity!

4. There is no reason to connect the negative of the lights to earth, but it won't do any harm. I suspect it is shown in the diagram because some lights do have a connection to earth and they don't want people to think they have to isolate the lights for the circuit to work.

5. I would probably leave the regulator in circuit to start with. It works by reducing its internal resistance to divert excess current away from the lights - "clipping" any voltage peaks above a certain level. Unless you are going quite fast this is unlikely to happen with an old SA hub. However there is probably no harm in leaving it in place....but see the next point:

6. If the lights seem a bit dim it might be worth removing the regulator. The diode bridge will drop about 1.2 - 1.4 volts, reducing that for the lamps by that amount. Depending on the precise characteristics of the dynamo, your LED lamps and the regulator there may be some benefit to removing the latter. - I am thinking that the LED lamps probably draw less current than the original filament ones, so the dynamo output voltage will rise (the dynamo acts, approximately, like a current source - adjusting its voltage to maintain a certain current). How pronounced this will be depends upon a number of factors, so a bit of trial and error is needed. Better still, do some road tests with a multi-meter connected and fastened to your handlebars.

My own experience of this is with an SA FG (four speed with generator) driving B&M LED lights with standlight circuits built in. The setup works well.
by robc02
31 May 2023, 6:33pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey 4 set up Woes
Replies: 10
Views: 537

Re: Sturmey 4 set up Woes

......and unless the trigger is brand new they tended to slip out of first unless held in gear.
I dealt with this by epoxying a piece of steel so that it moves the spring to one side so that it presses directly above the ratchet teeth. It has been a big improvement:

ImageSA 4 Speed Lever Mod by SturmeyRob, on Flickr
by robc02
31 May 2023, 5:53pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey 4 set up Woes
Replies: 10
Views: 537

Re: Sturmey 4 set up Woes

Is it first or fourth gear that you can't get?

When engaging first you should feel quite strong resistance from an additional extra spring (it only comes into play when going from second to first).

Have you got the correct indicator rod? It is in two parts that screw together from either side of the hub. If not properly tightened it can lead to gear selection problems. Be careful when tightening, the thread is very fine and easily damaged. I had one that wouldn't screw together fully and I had to carefully clean the threads with solvent and a wire brush to clear them out.

The correct two part rod can be difficult to find, and I gather that some hubs may have been converted to take a three speed rod (it requires a different axle key as well).

I assume yours is an FW? If so, this diagram might be helpful:

https://hadland.files.wordpress.com/2012/07/safw.pdf
by robc02
14 May 2023, 9:52am
Forum: Does anyone know … ?
Topic: Seat Post -will it be a crime to destroy it?
Replies: 69
Views: 4984

Re: Seat Post -will it be a crime to destroy it?

I have sucessfully used two methods in the past - neither for the faint hearted (obviously I first tried the gentler methods described above !):

1. Heat the frame with a flame - ideally to dull red heat or thereabouts. I know that aluminium expands more than steel but, apparently (I think this info came from Brucey), the heat dries out some of the corrosion, reducing its volume and breaking the bond between seat post and frame. You may get away with a lower temperature, but this is the way I did it. I have done the same to remove the remains of a quill stem from a fork column.

2. Cut the post off just above the frame. Very carefully make two or more cuts down the inside of the remaining seat post. This can be done using a hacksaw blade with the bit you grip wrapped in several layers of tape. Basically it is a makeshift fine bladed padsaw. Once the cuts are almost at the frame it is possible to prise the remains of the seat post away from the wall of the seat tube with a hammer and small chisel or suitable screwdriver (preferably one that you don't want to use for driving screws in future!). The part of the seat post protruding above the frame makes for a good starting point.
As you can imagine, this process is quite time consuming and requires patience. There will inevitably be some light damage to the inside of the seat tube - I finished mine with an adjustable reamer followed by abrasive paper wrapped around a piece of steel tube.
by robc02
28 Apr 2023, 6:55pm
Forum: Bikes & Bits – Technical section
Topic: Brompton SA FW retro-drive
Replies: 16
Views: 1471

Re: Brompton SA FW retro-drive

Do you have the correct (N190 on the diagram) left side wheel nut? Ity is extended to give protection to the overhanging rod - when it is the correct length for the axle, of course. If you don't then you could always use the N200 type normally used on the right hand side.
If the rod still protrudes, why not shorten it and cut a new screwdriver slot in the remaining part? This way you won't have protruding rod that will inevitably get damaged and probably interfere with gear changes.
by robc02
27 Apr 2023, 11:08am
Forum: Does anyone know … ?
Topic: Quote for Painting a Dawes Galaxy Ultra
Replies: 21
Views: 8752

Re: Quote for Painting a Dawes Galaxy Ultra

It is a while since I've had a lob done, but it sounds a bit high to me too.
I have used this place near Junction 6 of the M6 in Birmingham:

https://motorbikepowdercoat.co.uk/

There are no published prices for bicycle parts but you might get an idea of them from the motorcycle prices, or give them a call.
by robc02
9 Dec 2022, 8:02pm
Forum: Bikes & Bits – Technical section
Topic: Brompton SA FW retro-drive
Replies: 16
Views: 1471

Re: Brompton SA FW retro-drive

4 speed levers are scarcer and often apparently worn at the 'detent' for 1st gear
Here is my mod to help the shifter stay in first:
ImageSA 4 Speed Lever Mod by SturmeyRob, on Flickr

A metal spacer is epoxied in place to push the spring across so that it presses on the detent directly above the ratchet tooth rather than to the side.
I routinely use an FM on my drop bar commuter cum all round winter bike, and an FG on my Humber roadster. Both bikes' shifters have this mod.
by robc02
16 Nov 2022, 2:30pm
Forum: On the road
Topic: Hedge Flailing and Debris
Replies: 25
Views: 2078

Re: Hedge Flailing and Debris

I changed job just over a year ago, so my new commute is 12 very rural miles each way. During my first winter I had numerous punctures ALL due to hedge flailing debris. So far this winter I have had one, though it was a slow one that I discovered the next morning. (It turned out to be two thorns in the same tyre).

Most of the time I was on 32mm Continental GP 4 Seasons, so not the most robust tyres but not lightweights either.

I have been contemplating whether to:

1. Switch to something like Marathon Plus, knowing that they will puncture less often but will be a major hassle to get off the rim (in the dark, in the rain and covered in gritty mud) when they do puncture.

2. Use slime filled tubes or carry a can of slime inflator (seem to recall trying the latter a long time ago and finding it not very good - wouldn't work in very cold conditions).

3. Just continue with nice feeling tyres and put up with punctures!

Number three is winning at the moment.