coffeecherrypie

So I'm helping a friend modernize an old bike on the cheap. 126mm spacing, freewheel, downtube shifters. He rides in the city and does not want to reach down to shift any more. But he does want to keep the drop bars. New wheels are not in the picture. It looks like one might be able to get indexed shifting from the brake levers with only two rather economical purchases:

• 7-speed freewheel to replace 6-speed freewheel.
• 7 speed brifters, either ST-A070 (Tourney) or Microshift R7

I imagine figuring out if the existing derailleurs would work is a matter of trial and error. But my question is, has anyone done this and ended up happy with the result? Or is the experience bound to be sub-optimal?

HillRider

A Shimano 7-speed freewheel and those 7-speed brifters should work well with any Shimano 10-speed or earlier road rear derailleur or 9-speed or earlier MTB rear derailleur. You should be able to find a lot of 7,8 or 9-speed older group rear derailleurs at low prices from an LBS's NOS or used inventory or from a bike co-op.

coffeecherrypie

Thanks. What about the 6-speed derailleurs currently on the bike? Is the cable pull different? They are Suntour somethings.

Ferrouscious 

Most likely they will not work. Cable pull is different.

mitchmellow62

Sunrace makes 7 speed freewheels that are Shimano compatible. I have one installed and it has performed well with shimano shifters. I haven't checked current prices but they were cheaper than Shimano when I purchased it.

mitchmellow62

I'd try the suntour derailleur before tossing it. Sometimes they work with alternate cable attachment. I'm using a Suntour alpha 3000 with the Sunrace freewheel and Shimano shifters.

HillRider

+1. Particularly since they are Suntour, not Shimano and not likely to be compatible.

canklecat

It can work with the right rear derailleur.

I have those MicroShift R7 shifters. No problems. They're plasticity inside but has been reliable. Metal shift and brake levers. Everything is smooth and crisp.

However they extended the reach too much for comfort so I had to switch to a shorter stem or compact drop bars. The FSA Omega compact drops are great values. At the moment I'm using a 110mm stem with the FSA bar, but anything down to 90mm was comfortable without being too upright or twitchy.

I've mostly used a Shimano 600 Tricolor (Ultegra) 8-speed rear derailleur with the MicroShift brifters on a couple of bikes. No problems with 7-speed freewheels or cassette wheels.

Highly recommend SunRace chromed 7-speed freewheels and cassettes. The teeth and spacing are compatible with both my Suntour Acushift and Shimano STI setups. Better than the low priced Shimano 7 speed freewheels and cassettes that are still available.

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Amt0571

I rode a bike with Microshift R8 brifters and RD for 5 years. They felt a bit "harsh" when shifting and were not as precise as higher quality shifters, but they worked perfectly and didn't give me any issues. I didn't use them for light riding, as it was my only road bike for that period and I rode that hard.

Given how cheap they were, I think you could buy an RD if the one he has is not compatible.

coffeecherrypie

Thanks for the helpful replies folks. I think I must have an 8-speed RD somewhere in the parts bin, I will dig it up when we proceed.

coffeecherrypie

OK now I'm confused again. I was just looking at new Tourney derailleurs just in case a purchase turns out to be necessary. There is a 6/7 speed model, the RD-TY300-SGS, and also a 7/8 speed model, the RD-TX800.

You can see my question...if the cable pull between 6 and 8 speed shifting is different, then why can 7-speed go with 6 *or* with 8? And if the cable pull isn't different, why isn't there a 6/7/8 speed rear derailleur?

Thomas15

I did the same with the same opinion of the results, including the longer reach. Works really good though. I swapped out the original SunTour FD and RD for new Shimano Claris front and rear. I had to install inline cable adjusters for additional adjustment and the Claris FD was a pain to dial in but I got it. Put a Shimano 7 speed freewheel to replace the SunTour 6 speed FW.

In my application I have 27x1 3/8 tires and the original bike had suicide brake levers which incorporated the brake quick release. I wanted to get rid of the suicide levers and did but this was another problem with an associated cost.

So, my opinion? The conversion can be done. Cost? Figure $60 for the new shifters and $30 for the 7 speed freewheel. That's $100 Unknowns include but not a conclusive list bar tape, cable adjusters, SIS derailleur(s) as needed, chain replacement(?), brake hardware, cables. The cost can get out of control very easy. You never really know what's behind the living room wall until you open it up.

coffeecherrypie

Thx for the relay of experience. I should have parts boxes with all the odds and ends needed, so additional costs won't be too bad.

philbob57

I used a Suntour V-GT Luxe for a year with indexed DT levers. Maybe 90% of my shifts were fine. I finally got annoyed by the 10% that failed (either multiple cogs or no cogs) and got a 10 speed Microshift rder (sometimes called R10, other times, R47). I much prefer all shifts going where i want them to go.

andrewclaus

I did a budget brifter job a few years ago. I volunteer at a bike co-op and we often get seized up brifters donated on old bikes. One set couldn't be fixed with the usual ultrasonic bath and lubrication, so I asked if I could take it home and take it apart. I found a very stuck pawl and was able to free it and get it back together. Then I found an old Shimano RD in the scrap bin. I had to buy a down tube cable stop clamp and shifter cables and housing. Total cost was under $20, but it took a couple of months to salvage the parts. If there's a co-op in your area, that's a great source for used parts. Good luck with your project.

veganbikes

Before I would waste time and money on Tourney I would look at Gevenalle I have a set of the Audax levers and used older Dura Ace 9 speed DT shifters and they are great. You can get them with shifters as well in index or friction.

Amt0571

I'd go with Microshift instead of Tourney. They may be chinese, but the R7 is of way higher quality than Tourney.

Darth Lefty 

Campagnolo 10 speed ergos also make the right pull or close enough for a 7 speed or 8 speed Shimano SIS system. They were a little north of $100/pair with cables from England. Though I heard somewhere else here on BF that they were getting discontinued

fishboat

Did a drop bar conversion recently and found a new 3x7 Tourney set for a heavily discounted price. The Tourney shifters run Deore XT mtn front and rear derailleurs..they work great. The shifting mechanisms are set up a little different, but the shifting itself is just as clean as the Tiagra, Ultegra, and Dura-ace shifters I have on road bikes.

canklecat

Good description, pretty much my impression of the MicroShift R7. They can be a bit clangy, depending on the handlebar and frame. Shifting sounds were a bit more abrupt with some drop bars and on a carbon fiber frame, due to audible resonance.

I worried it would wear out quickly or break, but it's been fine in regular use for a year and a half. The brake levers have a good feel, plenty of leverage, smooth without excessive resistance compared with my older aero hood brake levers from Shimano (600 Tricolor), Suntour and others. The hoods feel comfortable, good shape, no problems after many miles and hours on long rides over rough pavement.

It doesn't feel as solid or clockwork-ish like my older Dura Ace 8-speed brifters, but those DA shifters have their own odd quirks. More metal-on-metal lockwork that requires good lubrication, and they aren't easy or intuitive to maintain, let alone repair. The old grease got gummy after many years. The MicroShift seems to be essentially self-lubricating through a clever use of materials that have minimal friction without needing much if any lube. Same as my old Suntour GPX Accushift downtube shifters, which uses some plastic/nylon washers to eliminate the need for lubes. And those things are still clicking along since 1989.

I have some 10-speed components for a budget build, including Dura Ace rear derailleur, cassette, chain, etc., and a 10-speed DA bar-end shifter from a time trial/tri-bike aero bars. But I probably won't buy Dura Ace brifters for the budget build. Can't justify it when the entire TT bike and pretty good components cost less than $200. MicroShift 10-speed brifters should be good enough.