[MikesChevelle]

Picked up a mint Centurion Sport DLX, It has biopace chainrings and Exage Motion Groups. Anyone tell me about Either of them.

I can have pics up too if needed, thanks.

 

[aengbretson]

What do you want to know? Exage is a portmanteau of "excellence" and "new age". The "motion" level means it isn't crap, but isn't top of the line either. If it's like the stuff I have on my old Giant, then it gives you the option of switching between friction and indexed shifting for the rear.

Biopace rings were Shimano's attempt at ovalized cranks. Their theory is that if you put the smaller effective diameter at the point where the rider has the greatest mechanical advantage (arms at the 3 and 9 o'clock positions), it will generate more than enough momentum to carry it through the "dead spot" (12 and 6 o'clock). However in practice, this generally works best for lower cadences and mashing the gears. It can feel kind of like "limping" if you try to spin quickly.

I like biopace for my commuter because I don't want to be pedaling like a maniac around town. I save that for hammerfests on my race bike. A lot of people don't like them though.

 

[MikesChevelle]

Well I think thats good enough info for me, just wanted to see if they were low end or not.

Picked up the bike for $80, should serve me well, came with a Cat Eye too.

<a href="https://tinypic.com?ref=30tnnmr" target="_blank"><img src="https://i28.tinypic.com/30tnnmr.jpg" border="0" alt="Image and video hosting by TinyPic"></a>

 

[Fantino]

I have the mirage group on a '94 Trek I bought new - now my commuter/rain bike. It's a very serviceable mid-lower shimano group. Has been smooth, precise, never any problems.

Nice bike for 80 bucks! :thumbsup:

 

[davcruz]

Excellent deal at $80! Where I live that would be a $250-300 bike easily. Can you say college town....no deals like that very often here.

 

[aengbretson]

Wow! That's in great shape! Very nice, especially for $80!

I don't know if your downtube shifters have the option of switching between friction and indexed (do they?) but I have bar-mounted exage motion shift levers that allow me to do so.

Again, that looks like a great bike!

 

[Amfoto1]

That is a very nice looking classic bike and a great deal for $80. Looks like it was never ridden... Still has the reflectors in the spokes and the spoke protector behind the rear cogs. I've got essentially the same frameset in storage with some Shimano 600 parts on it, but it's nowhere near as nice looking, needs paint, etc.... It might become a fixie some day.

I had biopace rings on a mtn bike years ago. I don't know if it's possible to swap those rings out for standard round ones (if standard round rings will fit the crank). Something to consider if you don't like them.

I'd be adjusting those handlebars to a way more sensible angle before I'd ride it very much.

And the front wheel quick release is normally on the LH side, and safer if it's positioned upward parallel with the fork leg. It's too easy to accidentally open a QR that's pointed downward like that!

 

[MikesChevelle]

That is a very nice looking classic bike and a great deal for $80. Looks like it was never ridden... Still has the reflectors in the spokes and the spoke protector behind the rear cogs. I've got essentially the same frameset in storage with some Shimano 600 parts on it, but it's nowhere near as nice looking, needs paint, etc.... It might become a fixie some day.

I had biopace rings on a mtn bike years ago. I don't know if it's possible to swap those rings out for standard round ones (if standard round rings will fit the crank). Something to consider if you don't like them.

I'd be adjusting those handlebars to a way more sensible angle before I'd ride it very much.

And the front wheel quick release is normally on the LH side, and safer if it's positioned upward parallel with the fork leg. It's too easy to accidentally open a QR that's pointed downward like that!

What do you mean about the handlebars?

LOL on the front wheel, didnt even notice that until I couldnt figured out why the Cat Eye was working, darn sensor was on the wrong side, then I noticed the wheel was backwards.

The bike has brand new vittoras on it too

 

[MikesChevelle]

Im thinkin yellow tape, seat and pedals, maybe even yellow striped tires, capture that late 80's feel