Showing posts with label biopace. Show all posts
Showing posts with label biopace. Show all posts

Saturday, September 24, 2011

Softening up

Back to the Xtracycle rebuild!
I posted a while back that the Xtracycle had blown bearings in the center bracket, worn breaks, cracked saddle vynil a busted gear shifter and probably some other things... Well I fixed it all up a few weeks ago and managed to 'soften' up the ride a bit by changing some components. 

OK I better clarify one thing first. 'Rebuild' is a bit of a misnomer. I didn't turn my wreck of a bike into an all purpose all terrain, 'pimped' to the max (I hate that word, pimped, but you get where I'm headed with this right?), urban utility bike. No I didn't really fix her up nice or spend hours rebuilding the bike with expensive custom parts that shine and make lovely click sounds when shifted into position. But I did get her back on the road and and a bit more comfortably than she had been before.

Total cost.... ? Not sure I think it all cost me about $10 and about 2 hours work.
Here's what I did.


simple indexed gear shifter
(Shimano SIS 6 speed shifter $0 10 minutes work)

I ripped out the old twin leaver rear gear selector with the complicated mechanism and replaced with a basic 6 speed Shimano SIS gear selector. This item cost me nothing, Cheep mountain bikes are all fitted with this style of gear shifter, I just ripped it off a wreck that was laying around. It works perfectly and now I can change gears! I could have got another of those complicated ones from the tip shop designed for a 7 or 8 speed hub but I couldn't be bothered fiddling around changing the gear cassette, besides I'd rather ditch the complicated shifter!

biopace
(Second hand Biopace chain-ring & second hand replacement axle and bearings)
For $10 I bought an old mountain bike minus the wheels for two reasons.
1. It had a biopace chainring.
2. The frame was large and I thought it might become my new Xtracycle

It turned out that the seat post had become fuzed to the frame and I ended up ditching it. I did however keep the chain-ring. I really like Biopace. I'm not going to argue the pros and cons, I know some people think it's crap but my old Shogun road bike has biopace and I've always found it easier on my knees than other bikes. Biopace may not necessarily provide more power but it does seem to 'Soften' the experience of riding on my knees!
The Biopace chain-ring did not protrude as far as the original chain-ring so I needed to find an axel for the center bracket that would match it... (The original one was just as worn as the one I'd been using on my Xtracycle bike (Raleigh). I pulled apart one of my old Giant Road bikes and used the axle and bearings from that. I scavenged the best of the bearings from all three sets, crammed in a bunch of grease and fitted it all to the bike. With a few adjustments I managed to get the axle to turn quite freely without too much lumpiness... (Well there is a little bit of a notch but what do you want from a set of bearings that have come from three different worn out bikes?)
I threw the chain-ring on having no idea if it would fit, or work (I don't get the maths, geometry or physics of what I'm doing I just look at stuff, size it up roughly, throw it together and hope for the best). It worked! There's only a couple of milimeter's gap between the smallest chain-ring and the frame, which means the front derailleur can't reach the small ring but I'm happy being able to use the two larger ones.
Now I'm running a Biopace chain-ring on my Xtracycle! Mock me if you like. I'm happy with the result. 


brake pad - bicycle
(Replaced brake pads with a little more tread)
I pulled some flash looking brake pads off an old bike at the Tip Shop. I think I paid a couple of dollars for them. Too much really they aren't very good but at least there's some rubber and my bike will stop.


flat peddles
(Flat surface peddle belonging to a Giant Hibrid bike)
Second 'Softening' agent I applied to the bike were these standard Giant Hibrid peddles. I had been using some pretty decent metal peddles which had good bearings and great grip but they were chewing up my thongs! I usually ride in thongs or bare feet and rarely wear shoes, the grippy spikes in the old peddles had already worn holes right through three pairs of thongs, including a couple of emergency replacements I'd scored from the side of the road! I've been riding on these peddles for about two weeks now and the bottom my thongs are completely in tact!

Having replaced these few items with stuff that cost me next to nothing my bike is back on the road full time! The net result of my efforts is that I now have a softer ride.

Long bike

Major points of softness I have added:

1. Gear shifter - I can change gears... ergo it's easier to peddle than when I'm stuck in top gear.
2. Biopace Chain-ring - Biopace eccentricity reduces the pressure needed on down stroke while maintaining constant drive to the rear wheel. Resulting in less pressure on the knees of rider.
3. Peddles - I don't do hard core BMX or mountain-biking. Flat peddles are fine for urban cycling on a heavy bike. These are softer on my footwear and softer on my feet.

Saturday, March 27, 2010

Riding in the rain

Tonight I rode home from a meeting in the rain! It was a beautiful experience.
Somehow everything seemed to be timed to perfection. We were sitting outside and at about 9:00pm a cool breeze came through... Then came the gust. Everyone who's lived in Darwin (or any other tropical place I imagine) knows exactly what to expect soon after that blast of cool air arrives! About 5 minutes later it hit! A beautiful tropical shower complete with the most amazing display of sheet lightening.

It came down pretty hard but by the time I was ready to leave the rain had petered out to a light drizzle and the sky was bright with a constant display of sheet lightening behind the clouds. It really is a wonderful experience to be in this kind of weather.

digression - a rant about my bike (and Biopace Chain rings)
I was riding a fairly old Giant Perigee road bike. It was a bike I got cheep from the tip and ended up giving to my mate Martin. Martin fixed the bike up and a friend of his was riding it a couple of years ago but it has since been returned to me and has been sitting in the yard for most of the past year . It was a pretty slick little bike to ride and I was glad that I'd lent/given it to someone who could be bothered to get it into reasonable shape. I hadn't really ridden it much since Martin gave it back so tonight I had an unexpected treat. The bike is quite smooth and fast too. Although it's a much smaller frame size than would normally suit me I felt very comfortable on it... with a good set of tires I didn't feel at all unsafe riding in the rain... Actually I felt like I was just gliding along. The biopace chainrings probably added to this feeling. Biopace is a kind of elliptical cog system that was introduced back in the 80s and lasted only until the early 90s. There are forums full of arguments about their merit, a lot of people don't like them, but as my knees seem to be getting worse, I am finding the biopace more and more appealing, based on comfort. It's funny because I've read the exact opposite in forums but generally the people who discredit biopace rarely seem to have ridden with it and then I keep coming across people who say that they've ridden 1,000s of miles on them and find them to be very good. I can only judge by my own experience and I'm quite happy. Even to the point where I'm contemplating fitting biopace to my Xtracycle.

Biopace
(The Giant Perigee with Biopace... I know it looks rough and needs oil)

I have several bikes and only ride with biopace occasionally, however I often feel much more comfortable on the biopace bikes, my knees are much happier too. Everything I've read suggests that they had little effect on efficiency or in overcoming any particular problems... People say biopace offered nothing special to the world of cycling and they eventually disappeared from the stores. It seems that the cycling world is quite fashion oriented and often quite fickle so it seems that by 1993 biopace went out of production.

Well I don't care what other people think of them! I like biopace I have two bikes with biopace chain rings and both are far more comfortable to peddle than any of my other bikes. That's good enough for me!


It's evenings like this that make me feel really grateful that I live in Darwin. It's the warm moist air, a mist of light rain as the storm passes, the smell of wet frogs (maybe Cane Toads) , wet vegetation and the amazing light displays! To ride in the rain wearing just a Tshirt and shorts is a very pleasant experience. My ride home brought me past what are usually pretty dark streets. However on this night I could see perfectly well just from the amount of lightening around. With each flash I saw the drops of rain glistening on my skin and glancing down the frame of my bike was beaded with rain drops. A fine rooster tail of water arched from the wheel in front of me as it picked up water from the black shining road. I wish I could describe the euphoric feelings that can be produced on a night like this. It's electric!