Search found 715 matches

by NetworkMan
20 Nov 2019, 5:58pm
Forum: Bikes & Bits – Technical section
Topic: A collation of dynamo/generator drag/efficiency data
Replies: 32
Views: 1326

Re: A collation of dynamo/generator drag/efficiency data

the standard StVZO test is to drive a purely resistive 12 ohm load. This means that if you see a test output (with a 12 ohm load) expressed in Volts, then the power (in Watts) is related simply by Power x 2 = Voltage cheers Power = V*V/12 for a 12 ohm load P = I * V I = V / R Therefore P = V square...
by NetworkMan
11 Nov 2019, 9:14pm
Forum: Does anyone know … ?
Topic: Trek Domane Al 3 vs Pinnacle Laterite 3 - which to buy tomorrow?
Replies: 7
Views: 483

Re: Trek Domane Al 3 vs Pinnacle Laterite 3 - which to buy tomorrow?

Are you sure the gears go low enough? Many people on here buy bikes with compact double 50/34 chainsets only to find the gears are too high for hills. This may be a significant issue if you have knee problems.
by NetworkMan
6 Nov 2019, 11:16am
Forum: Bikes & Bits – Technical section
Topic: The elasticity of mismatched Shimano drivetraims
Replies: 11
Views: 627

Re: The elasticity of mismatched Shimano drivetraims

Sooooo,in a fit of 'nowt to do on a wet afternoon' I wondered if the MTB Acera 22/32/42 triple on the Vaya would work with the Ultegra mech and if the Deore MTB shifter could operate across the three rings. You know what? I works like a dream. One snag though,that's if it is a snag,there's and 8mm ...
by NetworkMan
3 Nov 2019, 4:15pm
Forum: Bikes & Bits – Technical section
Topic: Are chain calculators always right?
Replies: 14
Views: 664

Re: Are chain calculators always right?

Like Brucey says, though if you really want to use the big-big combination, rather than just protect from an error in shifting, it may be kinder to the transmission to add four links rather than two. I guess it partly depends on whether or not you already had to round up to get the two links. You ca...
by NetworkMan
3 Nov 2019, 9:46am
Forum: Bikes & Bits – Technical section
Topic: Recumbent trike, 20” tyre suggestions please
Replies: 6
Views: 279

Re: Recumbent trike, 20” tyre suggestions please

If you want good punct*re protection and a good width at a reasonable price then 40mm Marathon greenguard is hard to beat. Perhaps, but if the design of the 20" (406?) tyre is like the 622 then the best compromise for on-road use is probably the 37mm See:- https://www.bicyclerollingresistance....
by NetworkMan
2 Nov 2019, 9:50pm
Forum: Bikes & Bits – Technical section
Topic: Are wider tyres typically taller?
Replies: 10
Views: 537

Re: Are wider tyres typically taller?

Why is it that a 37-622 is always 700x35 but for most other tyres both dimensions are the same? For example 32-622 and 700x32. I wondered if one dimension was height and the other width but I suspect that's not the case. There are pretty large variations between makes and types. I have Vittoria Hype...
by NetworkMan
2 Nov 2019, 8:01pm
Forum: Bikes & Bits – Technical section
Topic: Gravel Bike Gearing
Replies: 4
Views: 455

Re: Gravel Bike Gearing

It seems a little strange this transmission you are proposing. It is not one of Shimano's standard offerings but if you are designing a special I'm sure several people on here could suggest a design that would offer some or all of: Lower cost Lower weight Smaller gap between gears More durability A ...
by NetworkMan
26 Oct 2019, 3:04pm
Forum: Bikes & Bits – Technical section
Topic: Winter commute tyres
Replies: 9
Views: 466

Re: Winter commute tyres

Thanks, for your input, no one recommend Schwable ? On https://www.bicyclerollingresistance.com/road-bike-reviews Schwalbe don't have anything with such good puncture resistance as the Gatorskin. One I've never heard of is the the Prelli Cintutrato Velo which has better puncture resistance and roll...
by NetworkMan
24 Oct 2019, 11:40am
Forum: Bikes & Bits – Technical section
Topic: New member, new hybrid bike build
Replies: 8
Views: 327

Re: New member, new hybrid bike build

The main priority is light weight, I have a budget of around £400 maybe a bit more if I get exactly what I want. It's often thought that light weight is important but especially in your case it shouldn't be a high priority. When riding on level ground at a steady speed the weight of a bicycle plays...
by NetworkMan
23 Oct 2019, 11:23am
Forum: Bikes & Bits – Technical section
Topic: Hand built wheels.
Replies: 19
Views: 1178

Re: Hand built wheels.

For box-section wheels, you won't have to do much to go below 1500 grams, surely? Virtually any rim, hub and spokes would do the trick. Assuming that you mean 1500g for the pair, that's not true. For example medium priced ones ready built from Shimano are around 1800 g without skewers. With medium ...
by NetworkMan
23 Oct 2019, 11:13am
Forum: Bikes & Bits – Technical section
Topic: Chainline considerations when using triple chainset as double
Replies: 6
Views: 302

Re: Chainline considerations when using triple chainset as double

Thanks everyone. The reason for my question is I removed inner ring from a Stronglight triple and swapped bb to the only one I had. The result is the rings are still well clear of the frame, however when I fitted a double changer the only way I could get the cage to clear the chain on the inner is ...
by NetworkMan
22 Oct 2019, 7:25pm
Forum: Bikes & Bits – Technical section
Topic: Chainline considerations when using triple chainset as double
Replies: 6
Views: 302

Re: Chainline

Your question surely makes no sense without us knowing the length of the original BB axle. Assuming a chainring spacing of 5mm (pretty common) you would need an axle 5mm shorter so as to move the chainrings in by 2.5mm. That would align the midpoint of the outer rings with the original location of t...
by NetworkMan
21 Oct 2019, 4:05pm
Forum: Bikes & Bits – Technical section
Topic: Shimano upgrade gears only - which bits?
Replies: 12
Views: 461

Re: Shimano upgrade gears only - which bits?

The cassette on your Shoreditch I think was 11, 13, 15, 18, 21, 24, 28, 32, 37, 42, which has particularly big gaps between 13 and 11 (18%), 18 and 15 (20%), but 21 to 18 is not great either (17%) Your current effort has 11-13-15-17-19-21-24-28-32T, which with a 50/34 and ignoring the 50/11 as over...
by NetworkMan
21 Oct 2019, 2:54pm
Forum: Bikes & Bits – Technical section
Topic: Mudguards - a minefield
Replies: 18
Views: 816

Re: Mudguards - a minefield

Reading OP's earlier posts it looks like it's a Rockhopper Sport with suspension fork and no mudguard eyes so I can't help really.
by NetworkMan
21 Oct 2019, 2:18pm
Forum: Bikes & Bits – Technical section
Topic: Mudguards - a minefield
Replies: 18
Views: 816

Re: Mudguards - a minefield

I can help if your bike is like mine. At the front: 1. A hole in the fork crown - probably? 2. Screw holes in the fork blades close to the axle. At the back. 1. A chainstay bridge, just in front of the wheel. 2. A hole in the seatstay bridge. 3. Screw holes close to the axle rather like 2. at the fr...