KenNC

I came into a decent wheelset with an 8 speed cassette, and am considering using it on a vintage frame. BUT, I don't want to get into indexed shifting. Will friction shifting work with an 8 speed cassette? Would replacing it with a 7 speed cassette help, and would any particular type of rear derailleur work better with a set up like this?

Am comfortable with spreading the frame, but just don't want to invest in the rest of an indexed drive train at this point. If it all works out I might upgrade it to a "retro roadie" in the future https://www.bikeforums.net/classic-v...ergos-311.html

Tandem Tom

I would think it would work fine. I run a 9 speed and use barcon friction. Love them!!

rccardr 

Works fine, almost any derailleur will do the job. Details on component mix would help, though.

Pompiere

As long as the derailleur has enough travel to span all the cogs, it's not hard to friction shift 8 speeds. I have seen an older derailleur that wouldn't shift to the largest cog because it did not have enough travel, even with the low limit screw backed all the way out. The derailleur was meant for a 5 speed freewheel, which is several mm narrower.

JohnDThompson 

In principle, friction shifting will work with any number of sprockets on the rear cluster; you just need more finesse the more sprockets you have.

In practice, some shift levers may not have enough lever travel to sweep a large number of sprockets. E.g. Simplex "retrofriction" levers have a smaller diameter barrel than most other friction levers and require more lever travel for a given movement of the derailleur. But I suspect 8 sprockets should be well within the range of any friction lever.

jackbombay

My tall bike has a 10 speed rear that I shift with friction thumb shifters, but thumb shifters are better for friction shifting than DT shifters as you have more accurate control over a shift lever that is mounted to the bars as your hand is braced against the bar while you are operating the shifter, this is not so with DT shifters. I think 8 speed would likely be alright though, but bar end shifters would be better than DT shifters IMO.

AJI125 

Been considering this myself. Second to please share what shifting combo you’re thinking of. Some later DT shifters came with bigger barrels that should move more cable. Could look into a JTEK shift mate to move the RD more for a given amount of cable pull, or look to a RD that moves more for a given cable pull (IIRC from Shimergo charts, old index Campy is 1.4, new 1.5, and Shimano 1.7, so Shimano RD moves more for the same amount of cable pull). Pre-index isn’t on those charts, you might have to measure (envision some tape flags measured against a set point on the frame, shifting a few cogs of known spacing, dividing the RD distance by the cable pulled). And as mentioned above the RD itself may not span the full width. Most 7s freewheels are around 32.5mm wide, while an 8s Shimano is 35.4 and 8s Campy 36.9. Good luck!

EDIT: Found an old spreadsheet where I was messing around with the JTEK Shiftmate ratios (using their charts for compatibility, and standard cassette pitch and Shimergo chart RD ratios, what the pull ratio change was - note you can install these in both directions). This would be applicable if the RD moves where you need it, but your shifter doesn't pull enough cable to move it there. All numbers fairly approximate, but should be good enough for friction. Never tried this myself, YMMV.

• Shiftmate 1: 1.05
• Shiftmate 2: 1.10
• Shiftmate 3: 1.19
• Shiftmate 4: 1.26
• Shiftmate 5: 1.36
• Shiftmate 6: 1.55

ofajen

As noted, the two possible issues are the derailleur lacks range of motion to span between the outer cogs of an 8 speed and/or the shifter can’t pull enough cable.

If you are trying to do 8 speed, make sure to trim all slack from the shift cable when shifted down to the stop. That way, all of the shifter range is actually moving the derailleur.

If you have trouble with 8 speed, 7 speed should be easier because you would be spacing the cluster closer to the derailleur hanger on the dropout. So it lowers the required travel for both derailleur and shifter.

Otto

dddd

This is only tangentially related to the OP's questions, but I have learned to make every effort to provide any friction-shifted setup with the smoothest cabling possible.

This means clean cable housing with silicone-Teflon based lubricant and NO metal-on-metal contact along the cable's path.

The difference in shifting ease and accuracy makes quite a difference, and in some cases can even allow a shift lever with marginal cable travel to move certain derailers fully to their limits.

I ride in ever-rolling terrain around here, so shifting speed and accuracy tends to be more important.

Also, keeping the shift lever pivot and friction washers well lubricated can make another big difference in shifting performance.

caloso

No problem. I have 9-speed DA barcons set to friction on my TT bike. With a DA 7800 RD. I've run 9 and 10 speed Shimano wheels *and* 10 speed Campy wheels without any change.

As others mentioned, you have to be a little finer in your adjustments, but after a couple of shifts, it's second nature.

ofajen

Do you use a section of housing at the bottom bracket to avoid contact with a brazed on cable guide? I expect you could just run it under the guide and it would stay put pretty well due to cable tension.

Otto

Bogester 

Easy peasy. I’ve been doing it for a long time. You get pretty automatic and you shift right into gear just like an index shifter.

John E

My only index shift bike is my Schwinn, and I have always operated its thumb shift in friction mode. I currently run an 8-speed cassette on a 7-speed thumb shifter, and I have a 6-speed thumbie in reserve if the 7-speed wears out. (I found a 6-speed set at a very good price when the ratchet in my front shifter wore out.)

My equipment: 8-speed Shimano cassette, SunTour XC derailleurs and thumb shifters.

dddd

Cable housing can't easily fit within a typical bb cable guide, and wouldn't be easy to pre-curve so that it didn't add flex to the cabling.

But the plastic noodle material comes in all sizes and is easy to pre-curve, just a short section is needed so can be invisible.
Needs to be glued in place, I've used epoxy or silicone glue here on different builds.

79pmooney

I have bikes set up 7-speed with the SunTour auto-trimming DT shifter (never can remember its name) and my best bike has 9-speed and Superbe DT shifters. I'm pretty certain the auto-trimmer would run 8-speed. The rear derailleur plays a real part here. Some require considerably more cable pull than others. My 9-speed Campy Mirage has the DT lever folded nearly all the way back for low gear. My previous SunTours required a lot less pull.

fietsbob

Only issue . stroke width of RD to span a stack of 8+ cogs exceeds the amount of cable pull the lever drum winds up..

ofajen

Makes sense. Older Shimano derailleur ratio is typically 1.7, Campy is IIRC about 1.4 old and 1.5 new and my SunTour Cyclone ratio is more than Shimano so it takes less cable pull from the shifter.

Otto

stardognine

Good equipment there. 👍 I’m using XC derailleurs, and just switched from the regular Power thumbies to XT 7-speed thumbies. I’m still on a 6-speed freewheel, plan to move to a 7 as soon as reasonably possible. 😉 I never did find the better XC thumbies, and still want to try some, if I can find them. 😎

Chuckk

I remember close to two decades ago I got my first 9 speed cassette and was friction shifting with it.
I thought it SHIFTED LIKE BUTTER, thanks to the tooth shape working with the new chains, and said that we wouldn't ever have had click shifting if the old friction shifters worked like that.
And a bunch of really advanced bikers told me I was wrong, and I was just asking for missed shifts.
Glad to see that perception has changed.

However, I do think that clickity shifting will catch on, someday.

conspiratemus1

I have one bike whose Shimano derailer friction-shifts an 8-speed Shimano cassette with standard SunTour down-tube shifters (from the 6-7 sp freewheel era) without any modification at all. In the inner-most sprocket, the shifter lever is still comfortably short of parallel to the down tube. So this works flawlessly right out of the box. It is not at all difficult or finicky to shift and the modern ramped cogs make shifting really smooth, even under pedaling load. (Out of long habit, I still ease off a bit during shifting.) If you like friction-shifting an old six- or seven- speed freewheel, you will love friction-shifting an 8-speed cassette.

If your cassette is Campagnolo, you may run into more problems because Campag 8-speed spacing is wider than Shimano and so the cassettes are "fatter." One kludge I've used here is to replace the spacers with narrower spacers, salvaged from a worn-out 9-speed cassette, say. This is actually the easiest, cheapest solution that will work with all the parts you have, if you have (or can scrounge) the spacers, ...and you should use a 9-speed chain. It takes some ingenuity and trial-and-error to make sure your now-thinner cassette will still sit high enough on the freehub body to allow the lock ring to engage most of the threads in the freehub body without bottoming against it.