Fifty Plus (50+) - Why, yes, I *am* a mechanical genius....

As I grow ever-more fond of my vintage Univega touring/commuting bike, I decided it was time to jettison the oh-so-funky oblong Biopace chainrings and do some other maintenance upgrades as well.

I bought a new crankarm puller, and Friday night/Saturday morning I:


- took off the crankarm, installed the 3 new chainrings, re-installed the crank arm
- replaced the chain
- tuned up the derailleurs
- fixed a couple of loose screws on a fender
- checked the tire pressure and aired up the tires.

I then took off for a test ride, only to quickly discover that it didn't feel "quite right."

Once I took a look at the bike, and discovered my bone-headed mistake, I decided to grab a camera to document my achievement:


http://i36.tinypic.com/ftiloy.jpg

I like the look! Harley-Davidson has been using it for years with great success.

Don

Sheer genius!

http://www.ppchero.com/wp-content/uploads/2008/06/homer_simpson_doh_02.gif

Great for a lower center of gravity. Your friends will think you slightly eccentric however.

I like It!

Gets rid of the dead spot on the top of the pedal stroke. Now, if you could just figure out something for getting rid of the dead spot at the bottom of the stroke you'd be all set.

:lol:

Make sure you store those biopace away nicely. Or sell them on ebay. They're tre-desirable.

Gonna have to limit the beer intake the next time you wrench on your bike! :D

I've seen that done before. Not by me of course, but some of the other guys.

Wow, that's even more radical than the Biopace chainrings.

Now if you were clipless- You could pedal in 3/4 circles.

Another happy graduate of the Three Stooges Cycling Academy. Woop! Woop! Nyuk Nyuk:D

BRILLiant!

I sure wish I could see the images from work... I'll assume you did something like I would do until I see the pic. :)

I like the look! Harley-Davidson has been using it for years with great success.

Don

That was my first thought as well :)

I like the look! Harley-Davidson has been using it for years with great success.

Don
Yes, both cylinders hitting on the same stroke. Marvelous engineering.

This reminds me of the debate on tandems -- should captain and stoker be in phase, per convention, or 90 degrees out of phase, to operate like a 4-cylinder engine?

In the immortal words of my former Drill Instructor. "Lovely. Simply ****ing lovely."

Been there.;)

This reminds me of the debate on tandems -- should captain and stoker be in phase, per convention, or 90 degrees out of phase, to operate like a 4-cylinder engine?

And the debate goes on.We tried it and it did not work for us but if we wanted "Extra" speed- Pilot and stoker worked with one pushing down on the pedals and one pulling up. Had to switch over about every minute or so but for the Extra turn of speed for 5 minutes or so, it did work.

Cool idea but you need a different bicycle to pull it off.

See if you can find one of those vintage Roy Rogers bikes and set the cranks up that way. It'll give you the feeling of a galloping horse the way that we used to do when we were kids.

Sure makes it easier to stand up on while coasting!

If I posted a picture here of every fix-it job that I screwed up, it would make for a large photo album. I get so tired of it. I can almost always get it right eventually, but I'm just not attentive enough. I can see myself doing exactly what you did.

I wish I could say that looking at your pic makes me feel better ... but it doesn't. But it did make me laugh.

I think for that set up to work, both pedals have to be on the same side of the bike.

Race Cranking,
Put a set just like that on each side then heel-and-toeing.
You should be in the side ten.

I like 90 degree angles.

Quick! Call a patent attorney! Somebody's sure to pay big bucks for that innovation! :rolleyes:

SP

I bet that really screwed your cadence up.:D

Wanna get rid of those old rings that you didn't like?

Wanna get rid of those old rings that you didn't like?

They're headed to eBay soon unless someone PM's me...

I was going to wear them out but I realized that some people really want them so I figured I'd take them off the bike before they had much wear. I think they have about 1,000 miles on them (bike is from '83 but was in nearly new condition when I bought it...).

Been there.;)

+1 Yeah, me too, but only once. The embarrassment was so great, I been very attentive since then.

What he isn't telling us is that he rode for 37 miles on them before he figured out what was wrong.

What he isn't telling us is that he rode for 37 miles on them before he figured out what was wrong.

Well, I am not quite *that* stupid, but two related confessions:

1. I *did* actually adjust the derailleurs with the cranks in that position. I had the bike on the rack, and was pedaling with one hand while tuning with the other...just never noticed my mistake until I put the bike down and hopped on it.

2. One of the reasons that I tackled this job last weekend is that I was getting some mysterious clicking around my bottom bracket. I wanted to change the chainrings anyway, and the chain was worn, and my LBS told me that combination of Biopace chainrings / old chains sometimes produce an odd clicking, so I decided to change everything out at once and stop the noise. However, when I rode the bike yesterday the clicking was still there. :notamused: I hate noisy bikes!

Finally, on the way home from work, I started listening more carefully and adjusting my weight around and finally realized it was the seat post clicking, and nothing in the drivetrain. Last night I checked Sheldon Brown and of course he notes in his section on "noises" that people frequently are misled by seatpost noises and they think it's coming from the bottom bracket.

I greased the seat post, and the seatpost binder bolt, as several books/sites recommend, so hopefully that will fix it (didn't ride today).

I greased the seat post, and the seatpost binder bolt, as several books/sites recommend, so hopefully that will fix it (didn't ride today).

Remember now, the narrow part of the saddle faces the front of the Bike!!! :D

Thanks for the chuckle.

I get it......it is a triple instead of a compact.

Sorry-just couldn't resist fanning the flames!!

Hey-it would be fine for a one-legged rider.

With square taper spindles, you don't just want the crank arms to oppose each other; you want to put them back on the spindle in exactly the same mated orientation. This is expecially important on older/high mileage bikes. Mark one of the crank arms and the spindle with a Sharpie before disassembly.


Yes, both cylinders hitting on the same stroke.

Harley-Davidson 45deg single-pin V-twins fire on alternate strokes with a 315-405deg pulse. They would discover some 60 years after HD started doing this that it gives better rear wheel traction during acceleration and cornering. Not a big deal touring on a bagger; very valuble when flat-tracking.

tcs

1. I *did* actually adjust the derailleurs with the cranks in that position. I had the bike on the rack, and was pedaling with one hand while tuning with the other...just never noticed my mistake until I put the bike down and hopped on it.


After you discovered this, did you remove and reposition the spyder side? Please tell us "no..."

After you discovered this, did you remove and reposition the spyder side? Please tell us "no..."

Of *course* I repositioned the spyder side. Being the genius that I am, it is the only thought that occurred to me!

I finally found a website that is devoted to geniuses like me. If you enjoy feats of sheer brilliance, this website is worth a peek:

http://thereifixedit.com/

I don't see anything wrong with any of those fixes. What's the catch?