jh_

Got a road bike 2nd hand w 8 speed shimano 105 groupset and had it serviced to find out the rear shifter is messed up and needs replacing. My mechanic hasn't been able to get their hands on a new replacement for a while so i'm looking 2nd hand. I have 2 options in my area:

1. shimano tiagra 4600 10-speed shifters, like-new (person is upgrading to 4700)
   
2. shimano sora ST-3300 8-speed shifter, older & seems pretty battered
   

I called my bike mechanic and they suggested I stick w 8 speed shifters to give smoother shifting... But, don't most/all of the older shimano 8-10 speed shifters have the same cable pull? Which of these would be more compatible? TIA

Iride01 

If you are going to put all Shimano Tiagra 4600 or better yet, find you some Tiagra 4700 DR's and shifters, then I don't see why not put them on your 2d hand bike. Though a lot depends on the bike. You'll also need to upgrade the hub to a 10 speed freehub. But if you have to pay to have it done then maybe not much bang for the buck spent. And a half assed job by a newb DIYer won't be a good deal either.

Don't try to run 10 speed stuff with a 8 speed or even 9 speed cassette. Tiagra 4600 is probably okay for a 10 speed group, but the cable coming out the top just dates it as old stuff. But if it's free or close to it, then why worry about what I might think.

But if that 8 speed is a 3x front, then maybe you really do have the better option already installed on the bike. Even a 2x front with just 8 speeds might be decent if you don't have a lot of hills or have needs for specific gear ratios.

seypat

An 8 speed Microshift shifter will work.

hubcyclist

I'd concur with above, microshift r8 are actually pretty darn good shifters, from my experience, and I've used them with shimano derailleurs. But older tiagra 10 speed (pre 4700) would work too, just upgrade the cassette to 10 speed (the hub should be the same for 8/9/10 speed).

canklecat

Ditto, MicroShift, if you can find 'em -- even those are in short supply now. I've been swapping a set of MicroShift R7 7-speed brake/shifters between a couple of road bike for the past two years, no problems. They sound a bit clacky compared with my Dura Ace 8-speed brifters, but work well.

Currently it's part of a temporary setup on a Diamondback Podium frame I'm trying to decide on for a final setup. I think I'm going to convert the Diamondback to use with aero bars and older Dura Ace 10-speed stuff, including DA 10-sp bar-end shifters. Meanwhile it's a mish-mash of old Ultegra 8-speed derailleurs, 7-speed cassette (it's the only spare wheel I had around while I'm waiting to have the aero wheelset rebuilt), Ultegra 6700 crankset, 9-speed chain, and the MicroShift R7 shifters. Odd bunch of Frankenbike spares, bits and pieces but it all works. If the MicroShift 10-sp integrated brake/shifter units are compatible with my Dura Ace 7800 RD I might get those rather than the Shimano stuff.

Be cautious about the MicroNew stuff that often appears when searching for MicroShift. They appear to be very similar but user reports indicate the MicroNew stuff might not be the same quality. I've seen several reports of MicroNew shifters breaking soon after installation, while most MicroShift users seem to be satisfied.

And check the China Cycling YouTube channel for reviews of less familiar component brands that might be suitable. His reviews aren't just noncritical hype and he'll often criticize stuff that doesn't perform well or is built to unacceptable standards.

ARider2

Your local bike shop should be able to get the Shimano Claris 8 speed brake/shifter (presently available from QBP), or you may be able to get it yourself from online sellers.

Maelochs

No reason the Tiagra shifter wouldn't work but you might find yourself clicking for shifts which aren't there. If you aren't interested in upgrading to 10-speed, I wouldn't go that route. If you can buy the guy's whole 10-speed setup ..... but the 10-speed chain is narrower than the 6-7-8 chain. If you want to go with a 10-speed cassette you might find the 8-speed chain doesn't work, so you'd need to buy the derailleur, chainrings, and chain as well as the cassettte.

Honestly, I wouldn't trust used .... I have bought a bunch and only a few bad ones, but the prices are so high now, go Microshift or even Claris.

I have a Micronew 7 on one bike and it is fine, but I don't ride that bike enough to say the shifter would really hold up over time.

terrymorse 

Yes, according to bikegremlin.com, Tiagra 4600 10-speed shifters work fine with an 8-speed Shimano derailleur. Just swap out the existing 8-speed cassette for a 10-speed, and you should be good to go.

seypat

Where are you located at? I converted one of my wife's bikes from DT shifters to 3X Claris 8 speed. She doesn't ride that bike anymore. Shy prefers goofing around on her vintage mixte with friction shifting. I need to break it down and sell it. The shifters have low mileage on them. PM me if you're interested.

BradH

Unlike Shimano's newer shifters, those eight speed 105 STIs were designed to be serviced. These was a guy rebuilding them at one time, might still be. Ask over on the C&V forum and someone there will probably know. There was a set of Ultegra eight speed shifters for sale in the C&V for sale forum.