Search found 984 matches

by BigG
31 Jan 2018, 7:59pm
Forum: Bikes & Bits – Technical section
Topic: Custom 9 speed 12-32 cassette?
Replies: 32
Views: 2258

Re: Custom 9 speed 12-32 cassette?

its OK but (if it is the standard shimano 11-32 cassette) there are ~17% gaps in there between 12-14 and 18-21 that (pretty much) persist in the final gearing. There is no gear between 52" and 61". 26-34-42 and 12-32 cassette (say) gives the same range with much smaller gaps, easier doubl...
by BigG
20 Jan 2018, 1:20pm
Forum: Bikes & Bits – Technical section
Topic: Touring Gear Ratios for Wimps!
Replies: 108
Views: 6614

Re: Touring Gear Ratios for Wimps!

Like Tigerbitten, I have tried to maximise the number of discreet gears on my bikes but have a maximum of 21 with a 3 x 8 triple. My engineering training originally led me to believe that that evenly spaced gears throughout the range was the ideal to aim for - and a 13.5% gap seemed close to ideal. ...
by BigG
10 Jan 2018, 7:56pm
Forum: Bikes & Bits – Technical section
Topic: Touring Gear Ratios for Wimps!
Replies: 108
Views: 6614

Re: Touring Gear Ratios for Wimps!

The difference between the rolling diameters of 26" wheel/tyre combinations and their 27" equivalents is almost negligible. A 26' wheel with a 559-50 tyre is only 3% smaller than a 27" wheel with a 622-28 tyre. This is equal to about 1 sprocket tooth at the bottom end of the cassette.
by BigG
13 Dec 2017, 5:00pm
Forum: Does anyone know … ?
Topic: Best way to dry wet chain (post-ride)?
Replies: 48
Views: 2816

Re: Best way to dry wet chain (post-ride)?

Why bother? MickF's recommendation of waxoyl is sound; but if you keep your chain reasonaby well lubricated nothing more than a wipe with an old cloth is needed. Maybe some people's chains last longer than mine (I have only used cheap ones in recent years - mainly TAYA ) but I have never done more i...
by BigG
10 Dec 2017, 3:33pm
Forum: Bikes & Bits – Technical section
Topic: Changing to a suspension seat post
Replies: 14
Views: 1724

Re: Changing to a suspension seat post

The problem you may have, it that with a suspension seatpost you won't realize is a two-edges sword: on a rough road you don't feel the bumps but your wheels are likely to be under more stress. Think about it. The stress on the wheels is actually less with a suspension seatpost. The suspension tran...
by BigG
21 Nov 2017, 3:01pm
Forum: Bikes & Bits – Technical section
Topic: Touring Gear Ratios for Wimps!
Replies: 108
Views: 6614

Re: Touring Gear Ratios for Wimps!

Brucey's suggestion for a 6 x 3 gives good results but a little tweaking can improve it further. I use a 14-17-21-26-32-40 freewheel (a standard 5-speed with a TA Cyclotouriste 40 tooth inner bolted onto the back) with a 52/46/24 chainset (Suntour Superbe Pro 130/74 mm bcd) and find the ratios close...
by BigG
11 Nov 2017, 10:35pm
Forum: Bikes & Bits – Technical section
Topic: Why have a triple?
Replies: 63
Views: 2347

Re: Why have a triple?

Just a word of support for the now less common half-step system. Of my three bikes, the one with by far the largest gear range has an 8 x 3 gear set using 9-speed spacers on a 7-speed freehub. The 11-13-16-19-23-28-34-41 range with a 41 tooth middle ring gives me almost all of the gears I need in no...
by BigG
6 Nov 2017, 5:48pm
Forum: Bikes & Bits – Technical section
Topic: freewheels
Replies: 10
Views: 733

Re: freewheels

The best freewheel for your purposes would be the old Suntour 13-16-19-23-28-34. This gives reasonably uniform gear gaps (percentage, of course). They can still be found on ebay although this may take a few weeks of searching. Thy are extremely hard wearing with full sized teeth. Despite this, I fi...
by BigG
5 Nov 2017, 5:56pm
Forum: Bikes & Bits – Technical section
Topic: freewheels
Replies: 10
Views: 733

Re: freewheels

The best freewheel for your purposes would be the old Suntour 13-16-19-23-28-34. This gives reasonably uniform gear gaps (percentage, of course). They can still be found on ebay although this may take a few weeks of searching. Thy are extremely hard wearing with full sized teeth. Despite this, I fin...
by BigG
31 Oct 2017, 11:59am
Forum: Bikes & Bits – Technical section
Topic: Lost key Axa 'nurses lock'
Replies: 14
Views: 1144

Re: Lost key Axa 'nurses lock'

This thread is a good recommendation for the type of lock described. I use them on my touring and everyday bikes and have always believed that they were a good deterrent to would-be thieves. I use a lightweight chain anchored on the Dutch lock closing bar to attach to a convenient post. This deters ...
by BigG
15 Oct 2017, 8:29pm
Forum: Bikes & Bits – Technical section
Topic: Top Gear Size and its Influence on Average Touring Speeds
Replies: 50
Views: 2180

Re: Top Gear Size and its Influence on Average Touring Speeds

Having a triple up front make shifting slightly more tricky as it's not either/or like a double. Plus you need almost a vintage front derailleur to cope with the narrow range between the big chainrings. But someone will probably prove me wrong about that ...... :P A front triple half step and grann...
by BigG
15 Oct 2017, 8:18pm
Forum: Bikes & Bits – Technical section
Topic: Top Gear Size and its Influence on Average Touring Speeds
Replies: 50
Views: 2180

Re: Top Gear Size and its Influence on Average Touring Speeds

I do not think a big top gear adds anything to usual touring speeds because it is used quite seldom. I am still using the same top gear I used 50 years ago, about 90 inches - say 48x14. This is the same top gear I used when racing!!!!!!!!!!!!! Ok, I was never fast. My best 25 mile time back in 1975...
by BigG
14 Oct 2017, 8:07pm
Forum: Bikes & Bits – Technical section
Topic: 26" x 1¼" rims Airlite SF hubs - WHICH SPOKES and NIPPLES? Sorted :)
Replies: 11
Views: 561

Re: 26" x 1¼" rims Airlite SF hubs - WHICH SPOKES and NIPPLES?

I still have a pair of Harden large flange hubs dating back to 1952 (not the original bearings, of course). I had to replace the old 15/17G "rustless" spokes some years ago and used modern stainless steel 14/16G (Sapim IIRC). To fit these, I simply drilled out the spoke holes using (IIRC a...
by BigG
8 Oct 2017, 12:29pm
Forum: Bikes & Bits – Technical section
Topic: Gearing : resolving the 17t - 20t sprocket jump
Replies: 29
Views: 1618

Re: Gearing : resolving the 17t - 20t sprocket jump

Of course, half step gears can easily overcome the problem; but only old fogeys like me continue to use them.
by BigG
8 Oct 2017, 12:25pm
Forum: Bikes & Bits – Technical section
Topic: Dynamo wiring under stainless steel mudguard - what glue?
Replies: 22
Views: 1270

Re: Dynamo wiring under stainless steel mudguard - what glue?

If you use a continuous length of tape, be very careful not to stretch it when you apply it otherwise the residual tension will pull it off the guard where the adhesion is weakest. Most tape glues do not set solid but are merely very highly viscous and will creep eventually under tension. I have fou...