Rear cassette upgrade
 

Hi,
I want to attend my first century which has a lot of hills. I have realized that my bike needs a upgrade to tackle the hills. I was wondering if I could upgrade my rear cassette to something like 13-27 or 13-31. (and what should I buy that fits this) Here are the info about my bike and the gear set:

bike: Specialized Epic 1994
All parts are campagnolo.

Rear cassette: 13-23
Front: 39-52

Thank you in advance

Just start googling. It's probably an 8 speed. There will be several offerings. I had no problem finding a 13-29 10 Campy cassette for my bike after a particularly steep day.

Miche makes Campy compatible stuff.

I use a Miche cassette with 30 teeth for touring. Keep in mind though that your derailleur has to have a long enough cage to wrap the extra chain needed as you add teeth to the large cog. In my experience, the normal long cage Campagnolo derailleurs work fine up to 29 teeth, but 30 teeth won't go. The solution is to find a Comp Triple rear derailleur.

How many cogs on your current cassette? Do you in fact have a cassette-based system, and not a freewheel? Finally, what is the brand of the rear hub and the cogs - which might not be Campagnolo.

Without this critical information, you're going to get pages of misleading and irrelevant discussion.

Such as for example, suggestion to slap on the common 13-29 10-speed cassette. Of course, this would require a complete drivetrain changeover, involving shifters, derailleurs and a new rear wheel. So at least $500 of new parts and $150+ of shop time.

If you have a 8-speed rear Campy hub, then no, it won't fit a 9,10 or 11 speed cassette.

OTOH, you may be able to fix your problem for less than $5. More info required from you...

I think it's all campy and it's a freewheel.
I'm not much familiar with all the terms in biking since I am new to biking. I have the pictures of my bike and the rear but couldn't post it since I'm new here.

Rough situation. On your bike, you need to get a Campagnolo rear cassette in 8 speed, which they no longer produce. Are you sure what the difference is between a freewheel and a cassette? I'm not a vintage campy expert, but I don't think they were producing 8 speed freewheels in 1994 (or ever?) Unlike with Shimano, they don't produce low end parts, so they don't really make 8 speed drivetrain parts any more. Also, if you buy new old stock products from that era, they're going to have a relatively tight spread of gears. Also, your rear derailleur isn't probably designed for bigger than a 26t cog--you may be able to get it to adjust to a very slightly larger cog, maybe 28t. Miche Primato M Drive 8 speed cassette Campagnolo compatible | eBay would be your best bet, but you will likely have difficulty setting up your rear derailleur to clear the largest cog.

Switching to a compact crankset may be more fruitful/easier.

Campagnolo never made a 8-speed freewheel. Hopefully you have a cassette system.

If you have a standard Campagnolo short-cage rear derailleur, it will accept a 28 tooth rear cog, if you size your chain carefully.

Adding a 28 tooth cog to your existing cassette should cost less than $20 and take 15 minutes.

Realizing the same gearing with a compact crankset will cost around $250 and take an hour of shop time.

A totally unnecessary 'upgrade' to 10 or 11 speeds or whatever will consume at least $500 in new parts and 2 hours of shop time. If they are good...

Your choice...

Before going any farther with this it is very important to know exactly what you are dealing with. You have not even stated how many cogs there are on your freewheel/cassette. These details are important in order to determine what upgrades are going to be possible

I'd install a triple crank, with 30x23 like 39x30 and 26x23 like 39x35. Left ergo levers will run triples, you'll have the same gears for flatter parts of your rides. and period-correct Racing-T parts won't be very expensive.

I would not run a compact crank, which only gives you one more on the low end and radically increases front shifting with a tight cassette. Running 50-34x13-23 9 cog I was constantly shifting from 50x21 to 34x15 and 34x14 to 50x19.

13-26 is the largest available Campagnolo brand 8 speed cassette. Miche makes a 13-28.

While theoretically you could get a pre-exadrive 13-30 or 32 from Campagnolo's mountain gruppo effort it'd be a collectible and priced accordingly.

Although you can swap freehub bodies so it will, and swap the 8 speed cam + front ratchet for 9 speed parts.

I did that when Campagolo discontinued my favorite 8 speed cassette (the 13-14-15-16-17-18-19-21) in 2000-2001.

Possible in theory...

I have done the Ergopower ratchet upgrade. Easy.

In contrast, I have a rear 8-speed Record-level wheel that I want to do the freehub upgrade on. I have been looking for 3 years for a suitable donor freehub.

And I volunteer at a bike Co-op, where I get to screen hundreds of pounds of donated bikes and parts per shift...

The freehub "stub" side of the rear axle is 12mm, with people reporting success transplanting cartridge bearing freehubs although I can't verify confirm that personally - I swapped mine around 2001 before the supply of NOS cup-and-cone 10mm axle 9 speed freehubs dried up.

@gfk_velo should be able to authoritatively confirm or deny compatibility.

Sorry for the late answer - only just seen this one ...
The 3 pawl-3 spring bodies used in the old 8s hubs are not interchangeable with the 3 pawl-1 spring bodies used in later sealed bearing hubs, even though the spindle bore is the same - the depth of the "tail" that carries the pawls is incorrect ...