Bicycle Mechanics - friction to index question

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geezerwheels
01-14-13, 05:05 AM
always willing to taunt the mischievous and vengeful gods of gearing...would there be any improvement to substitute the "friction with indexing" shifter, for the current friction shifter on my '79 Moto Grand Touring. it's otherwise equipped with a Suntour winner 6sp 14/34 FW controlled by a Suntour Vx GT long cage RD--or am I, as usual, doomed to failure, frustration, and even more needless expense?
see
http://www.ebay.com/itm/Suntour-Cyclone-Down-Tube-Friction-Shifters-with-Indexing-for-6-Speed-/350688963055?pt=LH_DefaultDomain_0&hash=item51a6b0e9ef
Doohickie
01-14-13, 05:09 AM
A better upgrade would be to put a freewheel made for indexed shifting (http://www.amazon.com/s/ref=nb_sb_ss_i_0_12?url=search-alias%3Daps&field-keywords=6+speed+freewheel&sprefix=6+speed+free%2Caps%2C235) on the bike. It has ramps that aid shifting, improving shifting performance even with a friction shifter. It gives performance almost as good as indexed without having to worry about whether the throws of the indexed shifter match your derailleur.
Airburst
01-14-13, 05:29 AM
A better upgrade would be to put a freewheel made for indexed shifting (http://www.amazon.com/s/ref=nb_sb_ss_i_0_12?url=search-alias%3Daps&field-keywords=6+speed+freewheel&sprefix=6+speed+free%2Caps%2C235) on the bike. It has ramps that aid shifting, improving shifting performance even with a friction shifter. It gives performance almost as good as indexed without having to worry about whether the throws of the indexed shifter match your derailleur.
Not all index freewheels have those ramps, but Shimano ones do, and it definitely helps with friction shifting.
I'm sure there's something about indexing and Suntour systems on Sheldon Brown's website. It may be of use to you here, but I don't have time to find it right now.
Edit: I found this, which might be of use http://www.sheldonbrown.com/upgrade-gears.html
cny-bikeman
01-14-13, 05:55 AM
It is the lever that provides the indexing, but it depends on a matched index-compatible deraillleur and freewheel, and is also helped by index-compatible housing. So going to indexing would involve considerable expense. The freewheel with ramps would be the best alternative to improve shifting. Depending on amount of wear on your current freewheel you may need to replace the chain as well. That may offer a side benefit, as chains develop some side play after a while which can lead to less crisp shifting.
Doohickie
01-14-13, 07:00 AM
Not all index freewheels have those ramps, but Shimano ones do, and it definitely helps with friction shifting.
I'm sure there's something about indexing and Suntour systems on Sheldon Brown's website. It may be of use to you here, but I don't have time to find it right now.
Edit: I found this, which might be of use http://www.sheldonbrown.com/upgrade-gears.html
Pretty much all modern indexed systems have ramps. If you buy a new part on Amazon, etc., it will probably be indexed. If the OP isn't sure, he can post what he is considering in the thread and we can confirm.
...would there be any improvement to substitute the "friction with indexing" shifter...equipped with a Suntour winner 6sp 14/34 FW controlled by a Suntour Vx GT long cage RD--or am I, as usual, doomed to failure, frustration, and even more needless expense?...
I have index shifting on my 7 speed SunTour Winner Pro. I think it can be considered an improvement as there are fewer reaches to the right lever; the majority of the time one click is all it takes for an adjustment free shift. Precise cable tension and B screw position is important with the SunTour index lever, and it produces a loud click, which can shatter the serene experience one becomes accustomed to in friction mode.
You could contact these folks http://www.yellowjersey.org/ to see if your rear derailleur will be ok; I don't think it will be incompatible. If not, I know a couple sources for the SunTour X-1 long cage derailleur that will be appropriate for sure.
cny-bikeman
01-14-13, 09:08 AM
The derailleur is not index compatible and the freewheel may or may not work - if it is original it probably won't.
fietsbob
01-14-13, 09:34 AM
You may now be coveting, the new, gear, and so, ready for a new bicycle ,
or just learn how to effectively shift , a friction shifted drivetrain.
Phil_gretz
01-14-13, 10:11 AM
You may now be coveting, the new, gear, and so, ready for a new bicycle ,
or just learn how to effectively shift , a friction shifted drivetrain.
I'm with Fietsbob on this. You don't need indexed shifting for a 6 or 7-speed freewheel. There is so little to be gained.
However, a better shaped freewheel will make shifting quicker and quieter. Something like a Shimano 600 EX 6-speed, but you're unlikely to get the wide range that you had. Any Shimano-compatible freewheel will shift a bit better with your Vx-GT. A new chain might be in order, too.
Good luck.
ThermionicScott
01-14-13, 11:16 AM
If your Suntour Vx GT expects the same cable pull as the later indexing RDs, it might work just fine. That's provided you stick with 6-speed SunTour freewheels. :thumb:
Retro Grouch
01-14-13, 11:24 AM
If it ain't broke, don't fix it.
You have a Suntour bike. If you're happy with the way that it shifts and rides now, my advice is not to mess with it. Once you start changing parts you may find yourself changing the shifters, freewheel, derailleur, chain, maybe even chainrings just to get it back to working as well as it does today.
Doohickie
01-14-13, 12:21 PM
If you leave the friction shifters on there and just put on a ramped freewheel you'll get a much better shifting experience (yes, even with a different brand). The derailleur and shifter really don't matter if you stay in friction mode and just change out the freewheel. It's a $20 investment to see if you like it and you can go back to flat teeth if you don't like it.
i had an old friction shifting 5 speed bike that I put a newer 7 speed wheel on, and found the friction got much harder to set just right with the HG style cassette than it did with the old straight tooth suntour 5-speed. while trying to dial in the sweet spot for a given gear, it always wanted to jump to the next one rather than just make a bit of noise letting you know it was off center.
Doohickie
01-14-13, 01:06 PM
I've been using SunTour Barcons; maybe the ratcheting action of those helps set the trim more effectively. To be sure, I end up in between gears once in a while and get a phantom shift, but to me, I think I'd rather have that than the old way where the gear just makes a bunch of noise.
after using friction shifting for 30 years, I'm a total convert to trigger SiS. I'm not riding drop bar road bikes anymores, so I've not tried 'brifter' style shifting, but I got my son's old road bike setup with indexed rear bar-ends (and 2x7 gearing, it was originally a 2x5). friction is fine in front.
fietsbob
01-14-13, 02:58 PM
hard to find replacement freewheels that are not index, now ... early, shifting, these days..
I jumped past, latest indexed derailleurs, to an IGH, myself .
IMHO friction is better in the front .. read all the people who have the chain noises they cannot resolve because the SIS FD just goes to a fixed center..
'
Doohickie
01-14-13, 03:03 PM
IGHs are "indexed" too, you know ;)
Airburst
01-14-13, 06:06 PM
IGHs are "indexed" too, you know ;)
As I recall, Fietsbob ran a Sturmey-Archer 3-speed hub with a friction shifter for a while. I know Sheldon Brown did. Just don't try it with an Alfine :p
zacster
01-14-13, 07:55 PM
I put a 10 speed, yes 10 speed, wheel on my old style Campy friction shifter bike, including a Nuovo Record derailleur. This is a Velomax Tempest wheel with an Ultegra cassette, so out of the freewheel era and into the modern era as well, with 130 spacing. I have to spread the 126 dropouts to get it in, but nothing severe, it just feels like a tight fit.
So how does it shift? It is absolutely flawless in its shifting. A touch of the downtube shifter makes it go into the next gear silently. It almost never goes between gears as the tight spacing means there are no in-between gears. I can run up and down the cassette with a sweep of the shifter and it just goes. Not only is the shifting flawless, the entire drivetrain is dead silent. The only problem I have is that it won't go into the largest cog without the derailleur hitting the spokes. This is an old style steel bike without a separate derailleur hanger, so I can't replace it. But being steel, I should be able to cold set the hanger back into alignment. It isn't enough of an issue to make me want to do this.
As everybody says above, the ramps are what make it all work so well. I don't feel like I need indexing on this bike, although I'll admit that brifters are more convenient than downtube shifters. And obviously, this is a mix of Campy and Shimano, usually a no-no, but this works so well.
Road Fan
01-14-13, 08:37 PM
On my Terraferma I have an Ultegra 11-28 10-speed rear with an older 9-speed Deore mech, and friction-shifting it is just as simple as Zac's! In friction mode, mixing brands does not matter one little bit.
Get the dropouts aligned, and even get the rear triangle cold-set. Then see if you can remove a link of two of chain. Rotating the cage will move it away from the spokes when in the big cog. It might cure your spoke rubbing.
Road Fan
01-14-13, 08:39 PM
i had an old friction shifting 5 speed bike that I put a newer 7 speed wheel on, and found the friction got much harder to set just right with the HG style cassette than it did with the old straight tooth suntour 5-speed. while trying to dial in the sweet spot for a given gear, it always wanted to jump to the next one rather than just make a bit of noise letting you know it was off center.
try a narrower chain?
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