Bicycle Mechanics - Questions about upgrades

Hope the group can help. Looking to upgrade 1990 era Specialized Allez Epic carbon lugged frame. Shimano 105 components with downtube shifters, 7 cog rear cassette, double in front. Questions are:
If I upgrade wheels, can I go to 8 cogs without upgrading derailleur(s)? Can I get a spacer to adapt the 7 cassette to a 8-9-10 compatible rear hub? If I can't adapt and need to upgrade shifters & dérailleur, will I need to cruise EBay to find components that will fit, or can more current / modern Shimano gear work.
I apologize for all the questions, but this is my first effort at such an extensive retro- fit / upgrade. I love this frame, have put many miles on it, and want to breath some new life into it. Thanks in advance!!!

Hope the group can help. Looking to upgrade 1990 era Specialized Allez Epic carbon lugged frame. Shimano 105 components with downtube shifters, 7 cog rear cassette, double in front. Questions are:
If I upgrade wheels, can I go to 8 cogs without upgrading derailleur(s)? Can I get a spacer to adapt the 7 cassette to a 8-9-10 compatible rear hub? If I can't adapt and need to upgrade shifters & dérailleur, will I need to cruise EBay to find components that will fit, or can more current / modern Shimano gear work.
I apologize for all the questions, but this is my first effort at such an extensive retro- fit / upgrade. I love this frame, have put many miles on it, and want to breath some new life into it. Thanks in advance!!!


The FIRST question on this build is: what is the rear spacing, 126mm or 130mm? Because it has a carbon frame with aluminum lugs, you can't spread the stays. If you have 126mm spacing just leave it as a 7 speed. You could put on a compact crank, Sora 7 sp brifters and current dual pivot brakes. They would give you a noticeable improvement in performance.

If the spacing is 130mm any 8, 9 or 10 speed group will work. Good luck with the project, I always like the look of the Allez carbon frames.

Tim

Wow, I ride this same bike and always love seeing them at events.

My 105 derailleur shifted an 8 speed cassette no problem. I did have difficulty adjusting it for a 9 speed, so I installed a new Ultegra derailleur, works fine. If you go 9 speed you will also have to add 9 speed chainrings, chain and shifters. Scout the catalogs, I used closeout Dura Ace 9 speed downtube shifters from Nashbar $18.00 ! You may also find a deal on Brake/Shifters. Also, mine had a spacer behind the cassette that I removed so I was able to run the original wheel w/ 8/9 spd but you would have to disassemble to check it out

I was concerned about fatigue in the original aluminum fork so I replaced it with an affordable carbon fork that matches the frame nicely. The only other changes were a carbon seat post and aero bar, the brakes work just fine.

There was an issue with the bonding of lugs to the carbon tubes at one point. This frame was recalled and re glued by Specialized. Listen for a small 'clank' when you accelerate hard. Chain forces pull the cassette forward, compressing the drive side chainstay and putting allot of tension on the non drive chainstay, i/e trying to pull the lug from its tube. Pay close attention to any gaps between end of tubes and the stop on the lugs. I would not recommend using this frame very long or hard on a trainer for similar reasons.

I figured most of this stuff out, and have done all of the work myself. There are plenty of reasons why not to hang ~ $500 in parts on this frame, but ... I love cranking it out, on one of the first sub 20 lb bikes. It has also produced looks of confusion from more than one Style Conscious rider down here, so that's cool too.

Good Luck

Jmatt
OC California