Bicycle Mechanics - Downtubes to STI conversion

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View Full Version : Downtubes to STI conversion


jaymobutterball
01-30-12, 07:44 PM
I'm looking for a little help folks. I'm trying to convert my downtubes to stir. My big question is do I need to change my retailers as well? I know I need the stops where the downtubes are and new cables but what about the retailers?


AlphaDogg
01-30-12, 08:13 PM
typed on an iPhone?

How many speeds is your drivetrain? If 8 or below, you will not be able to do an STI conversion without a whole new drivetrain.

FastJake
01-30-12, 08:20 PM
Impossible to tell without knowing the details of your bike. A nice clean driveside photo would be sufficient. You might be able to toss them on plus the cable stops or you might need to replace every bit of your drivetrain plus a new rear wheel.



If 8 or below, you will not be able to do an STI conversion without a whole new drivetrain.

Plenty of (mostly low-end, these days) 8 speed STI shifters floating around out there. If this is an early 90s bike with Shimano indexed shifting like 7S downtube all the OP would need are the STI shifters plus a new rear wheel with an 8S cassette, or a 7S cassette using 8S spacing.


benlees
01-30-12, 08:47 PM
http://www.bikeforums.net/showthread.php/361558-retro-roadies-old-frames-with-STI-s-or-Ergos?highlight=sti+conversion

AlphaDogg
01-30-12, 09:01 PM
Impossible to tell without knowing the details of your bike. A nice clean driveside photo would be sufficient. You might be able to toss them on plus the cable stops or you might need to replace every bit of your drivetrain plus a new rear wheel.



Plenty of (mostly low-end, these days) 8 speed STI shifters floating around out there. If this is an early 90s bike with Shimano indexed shifting like 7S downtube all the OP would need are the STI shifters plus a new rear wheel with an 8S cassette, or a 7S cassette using 8S spacing.
Sorry, I meant anything below 8. I phrased it wrong.

Retro Grouch
01-31-12, 09:37 AM
I'm looking for a little help folks. I'm trying to convert my downtubes to stir. My big question is do I need to change my retailers as well? I know I need the stops where the downtubes are and new cables but what about the retailers?

If you buy a new in-the-box set of STI's they will come with a set of cable stops that fit in the place of your downtube shifters. Your LBS probably has a drawer full of the things. If they like you, that might even be a gimmy.

dave35
01-31-12, 03:04 PM
If you really want to incorporate your old downtube shifters into an implement for agitating liquids, you'll proably need to attach them to some sort of handle. My preferred way of doing this is to put a length of threaded rod through both shifters, one on top of the other, and arrange them in a sort of propeller shape (180 degrees opposed). This will be the most effective for stirring.

If the staff at your LBS finds out that you used perfectly good downtube shifters for mixing cocktails, beating eggs, or some other quiche-eating task like that, they will probably still do business with you, but they will make fun of you and say nasty things about you behind your back. For that reason, changing retailers might be worthwhile, depending on how thick-skinned you are.

dave35
01-31-12, 03:06 PM
Off-topic, but might be of interest to OP: Shimano derailleurs (except for old Dura Ace and new Dyna-Sys) all pull the same amount of cable. If it's old enough to be from before the indexing era, a derailleur optimized for indexing will improve your shifting, but anything from ~1986 (varies with model) on should work just fine.

Unrelated fact #2: Shimano 8s bar end shifters are still available, and work very nicely. These will work better than the low-end 8s STI shifters currently on the market, will last longer than you will, and will cost about half as much.

gyozadude
02-01-12, 04:04 PM
And to add, I still was able to find some 7spd STI ST3300 levers that work great with older Shimano. Bikewagon.com may have some of the right, 7spd levers still available (and cheap $29) but you'll be hard pressed to find cheap lefties for the front crank. And the newer St3400-series levers have a different head design on the flight deck. But if you don't mind colour coordinating and don't have issues with rim labels being on backwards, you may want to try sourcing some double St-2200 lefties which are black and not silver. Still available off eBay I think for around $33, free shipping. Beware the guy in Ontario, Canada selling just the lever blade on the STI. This is NOT the complete brifter but a repair part that goes into a disassembled brifter.

But I've gotten 7spd brifters working on old Shimano 600EX 6207 rear derailleurs running an old HG 7 spd 12-21 FW. And it works flawlessly with a new Sunrace 7spd 12-25 FW as well.

But you'll need to source the boss/adjusters yourself. Around $10 - $15 online that go onto the braze-on downtube mounts (not to be confused with the STI lefty quick tension lever version for $30+). But not too bad a deal for going STI if you don't mind the black/silver lever combo.