On 2017-09-08 09:20, sms wrote:
On 9/7/2017 7:59 AM, Joerg wrote:
On 2017-09-06 17:25, Doug Landau wrote:
On Wednesday, September 6, 2017 at 1:29:59 PM UTC-7, Joerg wrote:
On 2017-08-28 15:59, AMuzi wrote:
On 8/28/2017 4:28 PM, wrote:
On Monday, August 28, 2017 at 1:59:20 PM UTC-7, Joerg wrote:
On 2017-08-28 13:43, sms wrote:
I replaced the chain that I broke on Saturday with one I
had in my garage that I must have purchased five to ten
years ago.

It has a connecting link and it says "Taya" on it. It's for
6,7,8 gearing. It seems okay, but I think that this is the
first time I've used a chain with a connecting link since
childhood. I looked up Taya and it's a big Taiwanese chain
manufacturer.


I still have a Sachs-Sedis 7-speed chain on my road bike
which I bought from a friend as NOS, for $6 which was the old
sticker price (the sticker had already turned brownish). No
link, mounted with hammer and anvil as usual. To my utter
amazement it doesn't show any measurable stretch after over
2000mi and sometimes I really put the coals on because of our
hills. Even the old Wippermann chains could not rival that. I
am very religious about chain cleaning and lube though.

The old 5-6-7 speed Sachs chains wore out three days after the
bike was junked.


The Sedis (later Sachs-Sedis) material and Delta hardening
process was not only exceptional but unsurpassed down to today
except for possibly Record chains. That ended with SRAM.


Why is that? In the automotive world such an advance in technology
is kept and further developed, not rescinded and chucked back into
the dust bin. Well, usually.

Simple - the motor runs quieter, and consumers buy it more readily.
Hence we saw plastic teeth on timing gears.


And they make that last 100,000mi before a PM swap. That's what it
says in my SUV's manual and when the old belts came out they still
looked like new.

The recommended timing belt change interval is very conservative. I've
had it done on my SUV at 100K and while the belt did not look new when
it came out, it was clear that it would have gone far longer without
breaking. There are several advantages to timing belts versus timing
chains, especially on engines where a long chain or belt is needed. A
timing chain needs to have a system to keep it oiled. Chains stretch
more than a kevlar reinforced neoprene belt. Chains are noisier. Chains
are expensive to replace and contrary to what some people believe, they
do NOT last "forever" just because there is no scheduled replacement
interval.


The best was my Citroen 2CV, the 16-horse version. Two meshed metal
gears (no belt, no chain). It also had no distributor and no external
belts to drive anything. The generator sat directly on the shaft and the
propeller to cool the air-cooled engine sat in front of that on the same
shaft.

https://www.schaalbouw.nl/citroen/2cveng32.jpg

--
Regards, Joerg

http://www.analogconsultants.com/