jdawginsc 

Anyone with experience shifting a 8 or 9 speed cassette friction with thumb shifters?

I have a few friction shifters but wondering if anyone had some luck with that long of a cable pull for 8 or even 9 speeds.

I can probably use spacers and just do 7 speeds but it is for a reimagined Gitane mixte gravel and town bike I am building up for my sister

pastorbobnlnh 

Not exactly the same, but I friction shifted an 8-speed cassette with the original Shimano barend shifters, which were designed for 5&6-speed freewheels with no issues. I would guess the older Deore thumb shifters could handle at least an 8-speed.

mrv 

I’m using old Suntour power ratchets with 8spd.
Shifting pull amount is fine. Like Grant at RivBike says friction takes a little finesse with your feet.

As always with friction, a little tweaking is needed to keep things smooth running.





ps
Russ at the Path Less Pedaled has been setting up 10 or 11 speed with friction. Not sure if RivBike shifters or microshift

thedriveside

Currently running Suntour Accushift 7s in friction mode on a 9 speed Shimano cassette, and the ratchet action matches the 9 speed spacing pretty wonderfully. It's been a blast, going on two years with this set up on a daily beater.

jdawginsc 

Perfect. Thanks all. I know that the cheapo SunRace ones I used for bike giveaways did not have the capacity for anything over 7 speed so I thought I’d see what might work.

Thulsadoom

I run a set of cheap Sunrace SL-M10 thumbies on a 9 speed with no problem.

jdawginsc 

Hmm. Interesting. Maybe I should revisit those since I have a set or two them on hand. Thank you! Do you run a triple as well without cable pullback?

bboy314

I’ve successfully used both Suntour and Shimano barcons for 9 speed friction setups.

jdawginsc 

Hmm... interesting option for straight bars.

Thulsadoom

(Hmm. Interesting. Maybe I should revisit those since I have a set or two them on hand. Thank you! Do you run a triple as well without cable pullback?)


Yes. Triple nine speed. Friction thumbies are pretty simple. As long as the spool is large enough and it turns far enough it'll move the cable enough for the derailleur to operate. With the Sunrace SL-M10s, you adjust the tension with the little screw on top.

jdawginsc 

They are definitely basic and simple. I actually had to adjust the last ones so tight they were difficult to shift. I’ve used them on 7 * 3 MTB giveaways so I know it works, unfortunately, though, the last set would not hold the front derailleur one the big ring without super tightening the tension screw. And I was barely able to get all 7 speeds with the full range of the barrel.

might have to try again...

Thanks for opening another option!

harrier6

I've been wondering about the mechanics of friction shifting 8, 9, 10, 11 speeds recently. Thumb shifters designed for 10-12 speeds are definitely larger to enable more cable pull, but there are many other factors affecting it. The cassette is wider, but the cogs and chain are narrower. 10+ has different cable pull ratio, and 8+ often have wide range cassettes. Difficult to imagine how that all affects total capacity or ease of shifting in my head without going out and trying it.

base2 

IME: The different pull of SRAM derailleurs means that the el cheapo SunRace friction shifters (& probably others) don't pull enough cable to reach all the speeds.

The solution to that is to cut a bit of material off of the SunRaces' mount to allow the thumb lever/barrel a greater range of motion. You might need to trim a bit off of both sides so that not only will the lever travel further, but also so that it starts with from a more helpful position as well.

The SunRace friction thumbie sets are only about $14 with cable & housing...So it's a pretty low stakes experiment.

How well this works with other makes/models/etc of friction thumbie...I can't begin to guess. Certainly something indexed is going to have lesser chance of success. The crux is the barrel diameter & the barrels range of motion combined with the derailleurs pull ratio.

EDIT: Most of the following is just me prattling on random musings of dubious value & is mostly not relevant to the original post. Feel free to ignore. I'm not sure the tangent that led me to type it anyway.

In another thread I mentioned using a TravelAgent at the derailleur...It's not the best solution. Mostly a "functional" one...& with a Shimano legacy pull derailleur, a definite PIA at that. But, if you were to turn the large diameter side of the pulley down smaller it would change the situation dramatically for the better.

Fortunately the Travel Agent halving the 2:1 pull of the SunRace shifter to 1:1 (or near so with 11speed or most any SRAM derailleur) at the derailleur should work ok with out issue. The derailleurs return spring power would double at the lever though. Experiments at Base2 Global Industries are on-going.

If the results are not satisfactory, the pulley wheel is made of a soft aluminum & I should think that with due care, the machining can easily done with the pulley chucked up in a drill sandwiched between 2 nuts on a piece of all-thread. The cable groove could be reinstalled with the edge of a flat file. A poor-man's TanPan, if you will. YMMV, & it would probably take a try or 2 to nail it right depending on luck/skill/what parts you are starting with. But the concept does work & a Travel Agent is a whole lot less expensive than a well engineered JTek or a TanPan.

John E

mountain bike: 3x8 with SunTour XCD rear and (8-speed) Shimano 12-13-15-17-20-23-26-30 cassette, shifted with SunTour 7-speed Accushift thumbie in friction mode. Works like a champ, plenty of cable takeup capacity. .

Barchettaman

Nothing to add re the technical aspects of the thread, but on that photo it looks like you’re having an absolute blast, and that makes me happy.

John E

Annual 4th of July parade in my elder son's neighborhood. That afternoon I attended another 4th of July parade in my own neighborhood, and someone yelled out, "A red, white and blue bike. Cool!"

One of the last made-in-America Schwinns, purchased in 1993 from a San Diego firefighter. Seemed appropriate ... .

ClydeClydeson

FOr the past few years my main ride has had 2x9 with Shimano 7 speed bar end shifters set to friction mode. Sometimes I miss precise click shifting, but usually it works just fine.

jdawginsc 

I thought about bar ends, but with a straight bar, it likely will result in misshifts by accidentally moving it .

canklecat

I wish SunRace made an 8-speed version of their SL-M10 bargain basement thumbies. As cheap as those things are they work really well. I used them on my then-7 speed cassette Univega for about a year after the original indexed shifters became unreliable. But I'm not sure the SL-M10 would cover my current 8-speed cassette.

I have a set of older Shimano SL-L422 downtube friction shifters, nominally 6-speed, that can cover up to an 8-speed cassette. I've considered getting an adaptor to use them as thumbies or bar-ends.

My 8-speed Ultegra indexed bar-ends could also be adapted to thumby use with adapter. Currently I'm using those as bar-ends on my Univega Via Carisma hybrid with 8-speed cassette and 7-speed rear derailleur. The derailleur has a nubbin inside the housing that interferes with swinging the cage far enough to cover a full 8 speeds, but can be persuaded to do so in friction mode. In index mode the RD will shift into the largest cog, but under pressure it'll downshift. No such problems in friction mode.

I also have a set of Dura Ace 10-speed bar-ends, cannibalized off an early 2000s time trial/triathlon bike, that could also be adapted to thumbies and friction mode if necessary. But friction shifting in 10 speed would probably be fussy with more hunting to find the sweet spot.