Applied mineral exploration methods, hydrothermal fluids, baro-acoustic decrepitation, CO2 rich fluids
Newest Topics:

Gold at Okote, Ethiopia

Viewpoints:

Do IOCG deposits form from CO2 fluids?

How CO2 inclusions form from aqueous fluids (UPDATED)

Understanding heterogeneous fluids : why gold is not transported in CO2-only fluids

Gold-quartz deposits form from aqueous - CO2 fluids: NOT from CO2-only fluids


Discussions why H2 analysis by mass spectrometry is wrong



News:

Kalgoorlie Au data

Sangan skarn Fe deposits, Iran

New model 205 decreptiometer

Studies of 6 Pegmatite deposits

A study of the Gejiu tin mine, China


Exploration using palaeo-hydrothermal fluids

Using opaque minerals to understand ore fluids


Understanding baro-acoustic decrepitation.

An introduction to fluid inclusions and mineral exploration applications.



 Interesting Conferences:

-----2020-----

Geoconvention 2020, POSTPONED Calgary Canada, No date

PACROFI 2020, DEFERRED to mid 2022 Calgary Canada

AOGS2020, Hongcheon Sth Korea, CANCELLED Jun 2020

6th Archean, Perth, W.Aust. RESCHEDULED July 21-23 2021

SEG2020, Whistler, BC, Canada, POSTPONED to Sept. 2021

IAGS, Vina del mar, Chile, RESCHEDULED to Oct 24-29 2021

36th IGC, Delhi India. RESCHEDULED Aug 16-21 2021

ACROFI 8,Townsville, Qld, Aust. CANCELLED

-----2021-----
6th Archean, Perth, W.Aust. RESCHEDULED July 21-23 2021

ECROFI 2021, Reykjavik, Iceland

SGA, Rotorua NZ, Nov. 15-18 2021


Comprehensive Geology Conference Calendar


My touring bike saga

October 2014


My first solo unsupported touring trip was in SE Queensland in 2003, using my GT ZRX cyclocross bike. This was an aluminium frame bike, with no suspension.
GT ZRX cyclocross bike

This was replaced with a Cannondale R800 sport in 2005 which is an aluminium frame normal road bike but with "hedshok" front suspension and a seat-post suspension. this was much more comfortable for touring. I still ride this bike most days in Darwin after more than 120,000 Km.
cannondale R800

But these standard size 700c road bikes are hard to pack/unpack for airline transport, so i purchased a folding bike specifically for touring and ease of airline transport.

In 2008 I  purchased a "REACH road" folding bike from Pacific cycles, Taiwan, because it folded and had 20" wheels. Tyres for this size are more widely available than those used on other folding bikes such as Birdy and Brompton. The gearing was also properly designed to compensate for the smaller wheel diameter by using the shimano Capreo groupset with a 9 tooth smallest cog. Other folding bikes such as Dahon, use a standard mountain bike gear cluster with only a 12 tooth smallest cog, which results in a very low top speed on 20" wheels.

This bike came without a rack, so I made one myself with short legs to keep the rack low. It also had to be far back to allow space for pedaling with a pannier attached.

first reachbike and rack
2008

This rack was not strong and required frequent repairs. It was eventually replaced with a purchased "mountain" rack, which had adjustable leg length and was more robust.

reach on tour
2011

Both these racks kept the pannier as low as possible to give a stable ride even when carrying 20 Kg of luggage. But the rack had to be removed when the bike was folded, making packing the bike for travel complicated. After much practice, it took about 45 minutes to pack or unpack the bike for airline travel.

I used this bike for some 41,000 Km of touring including Europe, Turkey, Taiwan, China, NZ and Australia.
But In August 2014 the frame broke!

broken frame
2014

I returned to the factory near Taipei to repair the bike. This turned into a major issue, ending up with a new bike rather than a repair.

My bike used the old style frame which is no longer made. But the new style frame has some small but critical dimension changes that made replacing the frame impossible.
The brake mounting bridges on the new frame are some 5 mm closer to the tyre. This makes it impossible to use a 37mm wide tyre and only 25mm wide tyres will clear the caliper brakes. But 25 mm rear tyres are not strong enough to carry the touring load. I actually use a 37-451 tyre on the rear and a 25-451 tyre on the front.

I had to change frames from the "Reach-road"   to the  "Reach-trail" so i could use a 37mm wide tyre. But this frame does not have bridges for caliper brakes and is built only for V-brakes. These brakes are incompatible with road type shift-brake levers, so I also had to change to flat handlebars with mountain brakes and shifters. However the "trail" frame does have a built-in folding rack which is much more convenient than putting a separate rack on the "road" frame.

After much re-construction at the factory, where they were extremely helpful, I completed my Japan and China tour on this new bike.

new reach bike, flat bars
August 2014

But I find flat bars less comfortable than drop bars. On the very bad roads in China i had to keep my hands on the brake levers and could not relax and use the bar-ends. Drop bars allow a comfortable wrist position while still giving access to the brakes and gearshift. In addition, the V-brakes are a pain to maintain proper adjustment and extremely annoying during packing and unpacking the bike for airline transport.

I decided to banish the flat bars somehow.  I experimented with bullhorn bars and road levers, but still found these uncomfortable, so I have now used standard drop bars.

The main issue is the brakes. Road brake levers pull only half as much cable as mountain levers. One solution is to use "travel-agents" which double the cable pull. But it is impossible to mount these securely on a bike which folds. The other solution is to use "mini-V-brakes". It happens that the bike actually does have "mini-V-brakes" (Tektro RX5) and these do work (just) with road levers. (Genetic also make suitable mini-V-brakes.) You have to keep the wheel true and the brake pad clearance low and then road levers can work. A major problem with V-brakes is balancing the travel of the two pads. I found that the problem is poor lubrication and/or dirt in the mounting stems of the brake arms. Once I cleaned and carefully lubricated the brakes I could balance the travel properly. To prevent road grime from entering the bushings I cut a 3 cm. length from an old 700-25 tube and used it as a protective sleeve over the brake mount bushings. There is no adjusting screw on these brakes, so I added in-line barrel adjusters in each brake cable. Another issue is trying to release the brakes for wheel removal. The pad-rim clearance is so little that you cannot release the noodle from the toggle to open the brakes. I made a 3mm thick washer and placed this on the noodle tip so that you now only need about 1mm of compression to release the noodle from the toggle. Now you can open the brakes to allow wheel removal.


The CB90 cable adjuster/release

There is a better way to allow for brake adjustments. I have now installed a pair of  Shimano CB90 "brake cable adjusters". These are an in-line adjusters with an inbuilt release lever. The release lever mechanism gives 5mm of cable release to allow opening the brakes for wheel removal. The screw adjustment provides 10mm of tension adjustment. With these, there is no need to put a washer on the noodle. But you do need a slightly thinner than usual ferrule on the cable so it does not jam when you open the release lever.
shimano cb90 adjuster/release

I was also unhappy with the stiffness of the rear suspension. I opened up the shock absorber (which is easy to do) and filed down the elastomer 1 or 2mm in a wide shallow groove. This gave a noticeably more compliant ride without being too "loose". Be careful if you do this, you do not need to remove very much material to change the ride significantly and the amount will depend on your weight and touring load.

After all this fiddling I now have my preferred road brake-shifters and drop bar on the bike.

new reach with drop bars
October 2014

It has been a complex process to sort this out, but I like this much better.

The gears work just fine.  My concern is the brakes and the need to maintain a very small clearance between the brake pads and the rim and the need to keep the rim very true. Will this become an issue when touring rough roads with a touring load?

UPDATE - Jan 2015  

After riding 1500 Km in the Adelaide region in January 2015, the clearance between the brakes and rims was not an issue, and the wheels did not need to be trued. The CB90 cable adjusters were very useful and helped deal with the 5 punctures I had to repair on the rear wheel. It is now easy to remove and replace the wheels in correct alignment, although the tyres must be deflated. With the CB90 cable adjusters it is not necessary to remove the V-brake noodle, an annoyingly fiddly task.  


In 2018 I added another bike. The Cannondale Slate has fat 42mm tyres and is great for riding gravel roads without compromising paved road speed much, if at all. But this bike is not intended for touring as it does not fold for easy transport on aircraft. It has an aluminium frame, front suspension and hydraulic disk brakes.

cannondale slate bicycle