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by Geoff.D
17 Feb 2024, 2:41pm
Forum: For Sale - Complete bikes ONLY - state FRAME SIZE in title
Topic: Pashley Pronto - bargain price for quick sale
Replies: 2
Views: 543

Pashley Pronto - bargain price for quick sale

Pashley Pronto/Mailstar/Elephant bike. 18”. As original, apart from dynamo lighting. New cables and chain. Clean and tidy, but used condition.
I need the space, so anything over £100 will take it. Warwickshire/Oxfordshire border.
IMG_1632.jpg
by Geoff.D
20 Jan 2023, 9:10pm
Forum: Does anyone know … ?
Topic: Touring E-Bike required, London
Replies: 15
Views: 1315

Re: Touring E-Bike required, London

Many years ago I did very much the same, but by buying a motorbike for extended touring in other countries. I agree with the reply above - it's difficult to get rid of it ,within a convenient time scale, unless you're giving it away.

On the first occasion I went into a motorcycle shop and negotiated with the bike mechanic. On the second occasion I sat all day at the exit gates of a country fair with a big sign. Towards the end I negotiated with an interested young man. But, on both occasions, the buyer had the (obvious) upper hand.

There is another way of doing it. My sister and family were visiting from Canada. I bought an old VW camper. They used it. I sold it at my leisure after they left. They paid me the difference in price. It was a very cheap way of "hiring" a camper. Of course this method relies on you having a trusted buddy on this side before you come.
by Geoff.D
29 Sep 2022, 10:14pm
Forum: Campaigning & Public Policy
Topic: Trikes blocked by barriers on permitted routes
Replies: 66
Views: 7731

Re: Recumbent trikes, and possible difficulty with barriers

I ride an ICE trike, too. Those barriers are a right PITA, aren't they? Usually I do get through, but it usually calls for a dismount, some wriggling of the trike and fingers crossed that there's enough space. It usually works. Sometimes, as an addition to the barrier, the well-intentioned planners insert a "step" in the middle. This can be as troublesome as the barrier, requiring lifting, dragging and catching the underside on the top of the step.

HOWEVER ........ the good news is that I've never actually been halted in my journey. The one time I thought I would be (crossing a footbridge across the river Aire south of Leeds, on a NCN route) two young, strong cyclist (they all look young to me through my 73 year old eyes !!) simply lifted it up above their heads, camping gear and all, and walked down the steps.

I go, cross my fingers and trust that I can get round problems as they arise. It helps that I'm not precious about the looks of the trike (scrapes and scratches, etc). But, I guess, one day this approach may not work.
by Geoff.D
23 Aug 2022, 11:16pm
Forum: Non-standard, Human Powered Vehicles
Topic: IGHs on recumbents
Replies: 23
Views: 2042

Re: IGHs on recumbents

I have some real life experience of this. Some years ago (on XAP Bob's recommendation) I put a CS-RF3 hub on my ICE trike. I have an inner ring of 24 and a large cog of 32. On my 20" wheel that gives me a low gear (in direct drive) of 15".

Earlier this year I came down from Edinburgh to Warwickshire, taking as near a straight line down Borders and the spine of England (The Cheviots; The Northern Fells; The Yorkshire Dales). There were some stinkers on that route. 25%+ at times. I was loaded with camping gear, food and water. My hub worked fine, although I must admit I didn't quite need to drop out of direct drive, so perhaps I was protecting the internals somewhat.

Also, I have a Bafang 250w motor fitted to my "errand" bike (Pashley Sovereign with an SA X-RD5) on which I do the week's shopping pulling a trailer. I live in the Cotswolds and there are 2 quite steep climbs (18%+) of half a mile into town, and the same back. Even with the motor plus my own input the hub hasn't protested.

This isn't a quantitative analysis and I can't calculate what input torque I'm producing. However, I'm not Chris Hoy, and I ride quite gently. So, I have no worries about my current IGH on the trike, and would risk other Sturmeys at 15 gear inches.
by Geoff.D
14 Aug 2022, 2:36pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey X-RD5 pinion timing marks. - why?
Replies: 18
Views: 1006

Re: Sturmey X-RD5 pinion timing marks. - why?

Stradageek wrote: 11 Aug 2022, 7:44am
........... I only have so many (and a diminishing number of) brain cells :D

If you want some real brain teasers try working out why Dark Matter/Energy is deemed to exist, why Mercury is a regular naked eye morning star only when viewed from the Southern hemisphere or how the 'slingshot' effect is used to accelerate satellites traveling to the outer solar system.

Like your/my 'timing' conundrum I believe there comes a point where you need a mathematical equation to 'prove' it but a) I much prefer to visualise the answer and b) my maths is not up to it. :?
Aaah. .... that old conundrum. The inverse ratio between age and number of brain cells remaining!!! :D

Some more brain teasers - why does matter require the Higgs Boson in order to have mass? what's going to happen when a real life example of a "worm hole" is identified? why does the scientific method produce far more questions than answers and, yet, is considered "rational progress to understanding"?

I could go on "ad infinitum". But, there again, where on earth (or not on earth) is infinity, except in our minds?

I'm satisfied with Brucey's explanation, even though it only explains one specific static situation in the diagram. I take his word for it that the same reasoning applies if (for example) the planet pinion in the diagram were rotated by 90 degrees. I'm pleased that my thoughts were the same as his (the advance of the teeth on the planet compared to the sun) even though I overcomplicated the reason for this.

As for delving into the reasons as to why it works with prime numbers ....... I'll get back to you when I've worked out why the hare never did catch the tortoise!! :D

Nice to talk to you.
Geoff
by Geoff.D
14 Aug 2022, 2:16pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey X-RD5 pinion timing marks. - why?
Replies: 18
Views: 1006

Re: Sturmey X-RD5 pinion timing marks. - why?

jb wrote: 10 Aug 2022, 12:30pm Timing marks are needed on all compound planet gears. As the gear teeth need to all be in the same position to mate with the compound gears 'sun' gear. If they are not aligned more likely than not you wont be able to assemble it or if you do it will feel very stiff to turn.
Thanks, jb. I take your point and I'm beginning to understand why.
My initial thought as to why there might be misalignment between planet and sun (that it was related to the alignment of the two ball locking mechanisms relative to the axle) is wrong. The link to Brucey's explanation gives me more clarification. It's still about alignment of planet teeth to sun teeth, as you say, but more to do with relative diameters of the two pinions.
by Geoff.D
10 Aug 2022, 6:16pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey X-RD5 pinion timing marks. - why?
Replies: 18
Views: 1006

Re: Sturmey X-RD5 pinion timing marks. - why?

Stradageek wrote: 9 Aug 2022, 10:16pm
I asked the same question of the much missed guru (Brucey) and got this excellent answer viewtopic.php?t=125712&hilit=timing.

And as I observed in the link, if you rebuild a hub ignoring these marks it definitely runs rough.
Thanks for the link, Stradageek.

I had to read it a couple of times for it to sink in, and I'm not sure it quite answers my question. It explains why, given the layout of the planets and suns, the planets must be in that particular orientation to ensure that the larger planet tooth fits comfortably in the smaller sun pinion. He goes on to say that if one planet were adrift (say just one tooth out of sync) the the sun couldn't sit quite concentrically. I can see that. I can see (as you affirm) that being out of sync would make it run rough, or not at all.

But, I'm still struggling.

Does this mean that the need for timing stems purely from the ratio between the diameters of the smaller and larger planets? If so, then my previous idea (above) is a load of bunkum.
by Geoff.D
10 Aug 2022, 4:59pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey X-RD5 pinion timing marks. - why?
Replies: 18
Views: 1006

Re: Sturmey X-RD5 pinion timing marks. - why?

squeaker wrote: 10 Aug 2022, 9:49am
Geoff.D wrote: 9 Aug 2022, 8:31pmI'm not sure about this idea, Colin. I can't see Sunrace spending time "wearing it in" on a manufactured gearbox. And then dismantling it to carefully punch the timing marks.
The marks would be made on initial assembly... :roll:
Yes, my point exactly, Squeaker. But my question is why? Why does the orientation (timing) matter when each compound pinion is manufactured exactly the same as the next?

I believe I'm on the right track to link the orientation of the cogs on the smaller planet compared to the larger with the orientation of the ball lock of the smaller sun gear compared to the ball lock of the larger. If we were to say that the sun gears were "x" degrees advanced (one to the other) then the cogs of the planets must also be "x" degrees advanced when they mesh with the suns.. There must be only one orientation when they line up exactly with this "x" advance (signified by the timing mark). So, for all three planets to line up with "x" degrees advance they must all show the timing mark at the same time.

I haven't quite worked out the maths of it. It's all because there are fewer cogs on the smaller planet. So there may be only one position in which they offer the right "advance" to match the ball locking advance (sun gear advance). Were I better at maths (and knew the ball locking advance) II might be able to demonstrate it. But the idea seems OK.
by Geoff.D
9 Aug 2022, 9:14pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey X-RD5 pinion timing marks. - why?
Replies: 18
Views: 1006

Re: Sturmey X-RD5 pinion timing marks. - why?

Carlton green wrote: 9 Aug 2022, 8:51pm ............ IIRC the timing marks on the gears weren’t brilliant either.

TLDR; whatever you might think still make sure that you get the timing completely right.

For what it’s worth I’m a big fan of SA AW gears.

I agree. The timing marks aren't brilliant. They're small (but there's little space, I admit) and invisible if there's any residue of grease about.
by Geoff.D
9 Aug 2022, 8:31pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey X-RD5 pinion timing marks. - why?
Replies: 18
Views: 1006

Re: Sturmey X-RD5 pinion timing marks. - why?

531colin wrote: 9 Aug 2022, 6:24pm "worn in" to a particular orientation?
....as in no other orientation will be EXACTLY the same?
I'm not sure about this idea, Colin. I can't see Sunrace spending time "wearing it in" on a manufactured gearbox. And then dismantling it to carefully punch the timing marks.

I think I'm onto the right track in my reply to Roger (above). It's all about the orientation of the ball locks (ie the orientation of the small sun gear to the large sun, and the variation of orientation of the smaller cogs of the compound planet to the larger. Each planet pinion must "present" the exactly same variation to mesh with the variation between the large and small suns, which (in turn) is determined by the ball locking mechanism.
by Geoff.D
9 Aug 2022, 8:19pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey X-RD5 pinion timing marks. - why?
Replies: 18
Views: 1006

Re: Sturmey X-RD5 pinion timing marks. - why?

rogerzilla wrote: 9 Aug 2022, 6:07pm They have to mesh exactly with two other parts, that's why. I'm assuming these are stepped (compound) planets as in an old AM hub.
I agree they have to mesh with other parts, Roger. But, assuming each pinion is machined to the same pattern, why don't they mesh whatever the orientation? That's what puzzles me.
Could it be that, because the two sun pinions are at a set orientation to one another (determined by the angle of the ball locking orientation) the planets must also be at a particular orientation to mesh.

Ah....even as I write I'm having a eureka moment. If it were one sun and one planet it wouldn't matter. They'd just mesh. And if it were two sun and a compound planet, but both of same diameter, it also wouldn't matter. But, because the compound planet is of different diameters, the teeth don't line up opposite each other. The angular difference between the teeth must match the difference in the orientation determined by the ball locking mechanism.

I don't think words can explain it well enough. But I think I'm on the right track. Thanks for the prompt.
by Geoff.D
9 Aug 2022, 5:45pm
Forum: Bikes & Bits – Technical section
Topic: Sturmey X-RD5 pinion timing marks. - why?
Replies: 18
Views: 1006

Sturmey X-RD5 pinion timing marks. - why?

I'm not asking a question about a problem. It's really information for my own satisfaction that I'm after.

I've recently stripped and rebuilt two of these hubs. There's plenty of help on the internet and in the SA literature. It clearly says that lining up the timing marks on the planet pinions is essential.

One of the pleasures (not to say frustrations!) of delving into the mysteries of an IGH for the first time has been tracing the drive train through the gears and getting an understanding of the function of each cage, set of pawls, clutch, etc. But, for the life of me, I can't understand why these pinions need to be "timed",

Can anyone explain?
by Geoff.D
27 Jul 2022, 9:30pm
Forum: Cycle Camping sub-forum
Topic: Campsite near Belfast, heading south
Replies: 16
Views: 1282

Re: Campsite near Belfast, heading south

Traction_man wrote: 26 Jul 2022, 10:37pm
Geoff.D wrote: 26 Jul 2022, 9:15pm Earlier this year I camped at the Dundonald campsite, in the western suburbs of Belfast.....
A handy location, just off the Comber Greenway (NCN 99), so traffic-free cycling out from central Belfast (and also via NCN 93 from Belfast port), note though Dundonald is in the city's eastern suburbs, not west--https://goo.gl/maps/p4HbsjKkZmbf1iq98

all the best,

Keith
I'm embarrassed.
Of course it's in the eastern suburbs, Keith. Thanks for the correction.
I don't know why I made such a mistake ........ unless I'm further along the road to dotage than I'd care to admit !!
by Geoff.D
26 Jul 2022, 9:15pm
Forum: Cycle Camping sub-forum
Topic: Campsite near Belfast, heading south
Replies: 16
Views: 1282

Re: Campsite near Belfast, heading south

Earlier this year I camped at the Dundonald campsite, in the western suburbs of Belfast but in a leafy situation. Cycling from the ferry terminal wasn't too difficult. Into the city centre had cycle lanes and paths. Then out from the city centre was mainly on mixed use roads.
It's council owned and run. Good facilities and value. I booked on line and was given a code for the gate and the amenities. There's a separate patch for tents. Onward access to southerly routes is straightforward. I'd use it again.

https://www.dundonaldcaravanpark.com