70sSanO

I think I can guess the answer, but I thought I would ask.

My mountian bikes are setup with 13-34 (K) 7 speed cassette to a 24/34 double. The cassettes are spaced to 8 speed and I can easily run all 14 gears without issue.

As the years have gone on I've ridden trails less and less and would like to lower the gear ratio even more. I realize in the lowest gear I will be slower than a jogger pushing a double stroller.

I was thinking of going to an 8 speed 11-40, run it as 13-40 7 speed, to my 24/34. I would like to be able to run all 14 gears; well maybe 13 and not the big-big. I realize that there will be gaps. And no I am not planning on upgrading to a 10 or 11 speed and throw my stash of backup drivetrain components away.

I am running XT-760 SGS and XTR-960 SGS rear derailleurs so there is hopefully no capacity issue. I also realize that there are only 11 people in the world that use a Rapid Rise derailleur and only 7 of them live in developed countries.

Is there any reason to believe that I can't run a Wolf Tooth Roadlink with this setup?

Thanks!

John

FastJake

Funny, my MTB is 26/36 and 11-34 and I just bought an 11-40 8-speed cassette to try the same thing. I assume it will work with the Roadlink but I haven't actually set it up yet.

cpach

A RD-M960 has a capacity of 43t and your proposed setup is 39t, so the Roadlink should probably work. RapidRise sorta sucks, so as you push past the design intentions of the drivetrain the more a conventional derailleur will outperform its shift performance, but I'd certainly give your proposed setup a shot, it'll likely work. I'd also compare and contrast--you may be able to simply set the b tension really high and clear the 40t and get acceptable/possibly better shift performance.

70sSanO

When you get your 11-40 8 speed cassette, can you let me know how it is spidered/clustered together. All casettes are pinned together, and the pin can be easily removed. The better/lighter cassettes, and the cassettes with the larger cogs are generally not all full cogs that reach to the freehub body. Cheaper cassettes tend to spider fewer cogs. If the 28-34-40 cogs are spidered together and the rest are full cogs I'll take the individual 13-15-17-20-24 from one of my 13-34 "k" cassettes and slap the 28-34-40 behind it to get decent gapping.

John

70sSanO

Thanks! Yeah, I'll have to see. It had crossed my mind that the spring may not be able to get there. I started riding trails late in life. I got a Rapid Rise to make is easier for my wife to shift the right direction. I tried one and liked how I could dump a cassette if there was a sudden change in terrain. If was like old school single finger paintball and seemed faster than a couple of 3 cog thumb pushes.

John

FastJake

As far as I know, Shimano doesn't make an 8-speed cassette with more than a 34T. So I bought a Sunrace. Individual cogs, definitely not on a spider.

70sSanO

Thanks for the info. That will work.

My old setup is with a Shimano CS-HG50 "K" 13-34 7 speed, which is no longer made. I broke it open and re-spaced it to 8 speed, even though I'm only running 7. I messed around with a 12t, but found it not worth the trouble, so I'm not going to run an 11t.

With the Sunrace 11-40, I 'll run 13-15-17-20-24 from a 7 speed Shimano cassette and space them at 8 speed and then tack on the 28-34-40 from the Sunrace giving me a better spaced 8 speed 13-40 cassette.

I run a double and my left shifter is a big Suntour 4050 thumb shifter that pretty much fits in my palm. But it lets me trim it however I need to.

John

70sSanO

As I age my brain is much slower. Since I am currently riding a 13-15-17-20-24-29-34 cassette, all I really need is a 40t cog. I've decided to go that way rather than buy a cassette and throw 2/3 away. I have a lot of cassette spacers, so I just need to modify one that will get me to 3.0mm total.

John

FastJake

Did you find a place to buy just a 40T cog? I'd be interested to know.

70sSanO

I found them on eBay. I’m not sure of the quality, it is Fouriers, but the one I got was aluminum and cro moly.

It came with a 16t, which I won’t use, and a longer B screw. It was $30, but was the last one the seller had.

There are others of the same type for $38.

I also ordered a Roadlink.

John

FastJake

FYI, for future reference you can get the whole cassette for $24 shipped. And use the other cogs for whatever. https://www.ebay.com/itm/Sunrace-CSM...EAAOSwgLFehjVf

70sSanO

I saw that. Sadly, part of my change was based on the weight penalty in doing the swap. The Sunrace 11-40 is 450 grams (1lb). If I use enough heavier cogs from my HG-50 K cassette, I might be pushing 500+ grams, especially if I just slap the steel Sunrace 40t cog behind what I have now.

Not that I’m a weight weenie, but I like my current gapping, with the 29t, and this seemed like an easy way to get to 40t and see if I like it.

John

70sSanO

I installed the Fourier 40t (supposedly Alum/CroMo) 10spd cog. I used a Wolf Roadlink and a .5mm spacer between the 34t, to get it close to the 8 speed cassette spacing. I also added a 1mm behind it so the lockring wouldn't bottom out. A longer B-screw didn't cut it, I had to physically moved the derailleur forward to get it to shift into the 40t. Not wanting to install a Cambio Corsa type of device, I went with the Roadlink instead.

I'm running an 8 speed KMC chain and added 2 links to the length I had for the 34t (13-15-17-20-24-29-34-40). The rear derailleur is an XTR-960. The chainrings are 24/34 and I can use all 16 combinations, if need be.

I don't foresee the 40t getting a lot of use, but as the years go on, it gives me even more bailout. It actually shifts really good. Imagine, a 40t with a Shimano Rapid Rise derailleur... has to be a first.

John