Classic & Vintage - Downtube Shifter Question
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09-27-09, 02:18 PM
I have a 87 Cannondale that I almost finished getting back onto the road, and have hit a snag.
I got the bike with an 8 speed cog on the rear which I want to upgrade to a 9 speed in the near future. The snag that I am currently dealing with is that the Suntour downtube shifters that are currently on the bike, is a 7 speed index shifter. I am currently running a 7 speed rear cog so that I can at least putt around on it, but the spacing is off and it doesnt ride "well".
I have looked around and the only person that I have been able to find (so far) that sells 9 speed capable downtube shifters are the Dura Ace ones by Shimano. Those exact ones are a little steep for my budget and was wondering if anyone else knew of others that made them/and maybe could hook me up with a model number so that I can futher my search.
Thanks for your time.
09-27-09, 02:30 PM
Why not put a simple friction lever or a non-indexed ratcheting Suntour Powershift lever on the right hand side? This will handle any number of gears, you just adjust the travel stop screws on the RD to allow or limit the RD's travel. This would permit you to use 5,6,7,8 or 9 sprockets and to change between rear wheels with a different number of sprockets as often as you like. It's what I've done on a few of my bikes and I actually prefer friction shifting, it seems more satisfying somehow!
09-27-09, 04:27 PM
You'll probably have to go friction but you will need to find some levers that move enough cable for your derailleur probably. I went with a new campy centaur rear and a 7 speed on my 85 cannondale but with older campagnolo downtube friction levers. I have just enough throw to cover the 7 speed. I would have to come up with something different if I tried to go 8 spd or more. My question is what are you running for hub spacing? weren't 87's spaced at 126mm? I wouldn't recommend spreading the frame on those...
09-27-09, 07:01 PM
My question is what are you running for hub spacing? weren't 87's spaced at 126mm? I wouldn't recommend spreading the frame on those...
I too am curious as to the rear spacing on your 'Dale. If it came with an 8 speed (freewheel?) then it must have been spread somewhat. But I would also be a little hesitant to spread that 126 all the way to 9 speed territory.
The original Suntour 6 speed DT shifter will work fine with the spacing on a Shimano/Sachs 7 speed FW- the limit screws will act as the bottom 'index' and the index/cog spacing weirdness between Suntour and Shimano is all resolved with the difference between 6 speed ST and 7 speed SH. You can always go to a triple front if you need more gear. But curious as to which model this is...
09-27-09, 11:49 PM
I have no idea what model the Cannondale is, when I got it, it was a parts bike thrown together. The frame had been stripped and spray painted white, so I went to strip it down to the alum. and polish it out.
I didnt do the spacing myself. My LBS did the work, but he just put spacers on the rear hub of the rim (I am a newb so sorry if my lingo isnt correct) to make the 7 speed cog fit. It came with an 8 speed when I got it, and the rear derailer seemed to work fine, but he insisted that it didnt work correctly and that I needed to upgrade to a 9speed downtube shifter. But if I can use it as friction like the front derailer then I dont know what the hold up is.
09-28-09, 07:34 AM
Or if you really like indexed, there are 8s DT shifters around for less than the DAs. 8s almost as many as 9.
09-28-09, 09:40 AM
I am pretty sure the DA shifters are all you will find in 9spd. I am sorry you can only 'putt around' on that old 7spd bike. 7 seemed good enough when we upgraded from 6 LOL. why does the bike not shift well with the 7spd? are you using the Suntour DT shifter with a shimano cassette or freewheel? if most of your rear wheels are shimano 7 spd just find some shimano 7spd shifters and stick with it.
09-28-09, 09:47 AM
But I would also be a little hesitant to spread that 126 all the way to 9 speed territory.
No biggie. As a matter of fact, I wouldn't even worry about actually spreading the frame. Just shoehorn the hub in there... it's only 4mm. 9 speed is only 130mm... just like all of the other ones.
09-28-09, 09:51 AM
Do your existing shifters have a friction mode ? Some do. That will get you going for free.
Many of us put 130 mm wheels into old Cannondales without a problem. You just have to put a little muscle into opening the frame 4 mm when inserting the wheel. Not a big deal. Don't try to "cold set" aluminum though (permanently bending it to 130mm)
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