Search found 625 matches

by pliptrot
5 Oct 2021, 9:29am
Forum: Bikes & Bits – Technical section
Topic: why do Shimano do that with their BBs?
Replies: 2
Views: 265

why do Shimano do that with their BBs?

20+ years ago I bought a mountain bike with a 739XT group - including a 110mm UN72 BB and a triple chainset. The left crank was about 5mm further out than the right. Having been through 2 of the same chainsets, 2 frames and 3 BBs I can confirm that this is not a 1-off. I recently found a new UN72 on ebay, so that is now fitted, and had the same effect. I put ~4mm of spacers between the frame and the drive-side flange to get the cranks equally offset. But now the chain line is such that the big ring offers a perfect chain line with the 11 tooth (smallest) sprocket (8 speed). So why do they do that? For a while I used the bike with only the big ring and no front derailleur, and a 107mm BB from Tange offered a much better oreintation of the crank and chain line. But if I stick with what I have the largest 3 sprockets are not usable with the big chainring - the chain derails because the chainline is so canted. Even the middle ring to largest sprocket is no-go for the same reason. Weird.......
by pliptrot
4 Sep 2021, 11:36am
Forum: Bikes & Bits – Technical section
Topic: New Shimano 12 speed road (electronic only)
Replies: 53
Views: 1757

Re: New Shimano 12 speed road (electronic only)

The bicycle is a simple, low-tech machine, and all of the obsessions with more gears and guff about speed of changes and so-on is just that - guff. Indexed shifting and clipless pedals were undoubtedly big steps forward. The designs allowing hub bearings to be adjusted in situ was also of merit. But pretty much everything since then is just marketing - and makes the machine we love more fragile, faster wearing and less user serviceable. I am not yet that old, but I do yearn for the days when a bicycle was a tool - even high-end kit - deisgned to get you from A to B (sometimes at race speed, in a race) as efficently as possible. There is nothing - nothing- in the guff (that word again) about this new kit which talks about bearing design and efficiency, changes to offer more durability, or indeed anything which offers an improvement to those who must buy their equipment. The pure unadulterated pleasure of riding a fine bicycle has now been so sullied by this sophistry that I - like many- will be making our existing old kit last, somehow.
by pliptrot
24 Jul 2021, 7:44pm
Forum: The Tea Shop
Topic: DVLA...aaaargh!
Replies: 21
Views: 666

Re: DVLA...aaaargh!

Try doing similar things in Germany. You will never, ever criticise the UK civil service if you do.
by pliptrot
13 Jul 2021, 9:03am
Forum: The Tea Shop
Topic: Has your life changed?
Replies: 50
Views: 1299

Re: Has your life changed?

2019: 32 long-haul (>6 hrs) flights. 45 flights in total. Previous years more.
2020: 4 long flights, 10 in total.
2021: 0.

But I am now very good at understanding and directing people from the antipodes. Not sure I want to go back to the nomadic way of doing things, but my employer is old-school.

PJL
by pliptrot
6 Jul 2021, 1:18pm
Forum: Bikes & Bits – Technical section
Topic: Replacing XT v-brakes
Replies: 5
Views: 293

Re: Replacing XT v-brakes

Those are they. I have been informed that they can be disassembled, so I am going to do that and inspect all parts. They are on a Voodoo Bizango - my first Taiwanese built frame (bought off ebay as an interim measure while I pondered on a replacement for my Croydon-made jewel (crashed)) and it is my absolute favourite MTB. So I will persevere with 26" wheels and v-brakes. Sad really, but it was less than 20% of the cost of a UK built equivalent.
by pliptrot
6 Jul 2021, 9:40am
Forum: Bikes & Bits – Technical section
Topic: Replacing XT v-brakes
Replies: 5
Views: 293

Replacing XT v-brakes

I have XT v brakes - 1998 models with the parallelogram mechanism - and was wondering about their durability. They were always rattly but may be getting worse. Does anyone have any experience of failure on these? I may change them as a precaution but thought I'd canvass opinion first. The choice out there is getting much less.
by pliptrot
6 Jul 2021, 8:34am
Forum: Does anyone know … ?
Topic: How do tubeless tyres work?
Replies: 34
Views: 1327

Re: How do tubeless tyres work?

Marcus Aurelius wrote: 5 Jul 2021, 4:51pm I’ve yet to get any puncture in the tubeless tyres I use now, that haven’t been sorted by using a worm.
So you're an early bird then. Is this on your cost-as-much-as-a-car green bike?
by pliptrot
26 May 2021, 4:54pm
Forum: Bikes & Bits – Technical section
Topic: Bike designs which should be binned
Replies: 357
Views: 16155

Re: Bike designs which should be binned

There was thread on here some time ago about someone who ended up with serious facial injuries after their front wheel came adrift. It was stated that this had happened because those "lawyers lips" had been removed with rather too much gusto and there was insufficient grip between the (relieved) drop outs and the QR. All I can say is that my custom made frames from UK builders don't have them. The big company frames do, and they are an irritant.
by pliptrot
26 May 2021, 2:16pm
Forum: Bikes & Bits – Technical section
Topic: Bike designs which should be binned
Replies: 357
Views: 16155

Re: Bike designs which should be binned

I spent a lot of time as a youth YHA'ing with my father. I look back at his perseverance with SA 5speed hubs with wonder - they were unreliable and constantly slipped. He spent good money after bad on new internals trying to get them to work. No wonder the company failed. Sadly - as has often been the case - it took the Japanese to show the way with hub gears.

Also looking at the past it's amazing how Campagnolo survived. The C-record rear derailleur inherited all the terrible performance of the preceding Campag mechs but added weight. Yet it was still used to win multiple Tours de France, a decade or so since the Japanese -err- showed with way with derailleur gears. There's a common theme here.......
by pliptrot
25 May 2021, 7:53pm
Forum: Bikes & Bits – Technical section
Topic: Bike designs which should be binned
Replies: 357
Views: 16155

Re: Bike designs which should be binned

jb wrote: 25 May 2021, 7:24pm Cantilever and vee brakes should never have been invented. The time wasted setting them up on various bikes could have been spent inventing a self propelled cycle with built in toaster.
Gosh, methinks you have only been using cheap versions of these. The good ones (Shimano XT & XTR) are (were) simple to set up and reliable.
by pliptrot
2 May 2021, 10:32pm
Forum: The Tea Shop
Topic: I don't like living in England....
Replies: 2010
Views: 50040

Re: I don't like living in England....

.................
by pliptrot
25 Apr 2021, 9:14pm
Forum: Does anyone know … ?
Topic: Halfords In-Store Bike build problems
Replies: 52
Views: 2488

Re: Halfords In-Store Bike build problems

As a (real) professional engineer it pains me to see how casually the term "engineer" is used, and not just in The UK. But why worry? You might have spent 6 years at university and have the right to put the term "doctor" before your name but you will be paid the same as a bus driver. Anyhow- back to Halfords: it is - as everywhere and everything- a lottery who you get. I bought a bike from them (I have mentioned this before on here) and found a crack in the frame at the shop. 24 hours later they had rebuilt it on a new (much better) frame and it was A+ from the get go. I asked what the price adder was and was told 0. The bottom bracket threads had been greased, the gear adjustment was perfect and the cables were perfectly cut. I'd go back there before many of the LBSs I have dealt with. But the pleasant young man who did this has no doubt moved on. Possibly to university, and I imagine he was smart enough to read something other than engineering.
by pliptrot
21 Apr 2021, 4:04pm
Forum: Bikes & Bits – Technical section
Topic: Why your wheels resemble a pterosaur's neck
Replies: 2
Views: 592

Re: Why your wheels resemble a pterosaur's neck

Think of any other structure which can support 300x it's own weight........
by pliptrot
21 Apr 2021, 3:58pm
Forum: Bikes & Bits – Technical section
Topic: I've cured the rattle!
Replies: 38
Views: 1511

Re: I've cured the rattle!

We have a Nihola cargo bike. You don't know about rattles until you have ridden one of these. If you can imagine a round box designed to make a noise.........
by pliptrot
19 Mar 2021, 8:49am
Forum: On the road
Topic: Another aluminium VS carbon thread
Replies: 10
Views: 953

Re: Another aluminium VS carbon thread

chris_suffolk wrote:If I had a carbon bike, with a cheap group-set, then that's the one I would ride year round. But, decent carbon frames don't normally come with a cheap group-set, hence the second, cheaper, wet weather / winter bike - for me at least

Bikes are low technology, and with a modicum of skill and basic tools changing equipment - complete groupsets included- is simple. Surely it is better to find a fine frame, and change the bits to cheap or disposable stuff for the bad weather. After all, you can buy excellent Italian and Japanese components which are made to a very high standard and from excellent materials: the state of the art, so worth preserving. Carbon frames, on the other hand, present more of a minefield. Those who speak with authority suggest most are not up to much: products of large far-eastern factories built to a price. Having seen more than a few prestigious and expensive Italian frames cut in half after failure, one might properly conclude that the emperor does indeed have no clothes, and that anyone parting with thousands for a frame alone is being taken for a ride.