HerrKaLeun

20 mph on a road bike and you are spinning out? TdF riders have similar high gear and are able to race downhill on a blocked street.... I doubt you actually spin out.

My fatbike has a single 26T chainring and I can ride 20 mph.

You just need to pedal faster. 80 to 100 rpm is normal cadence.

Archinutt

I'm not spinning out at 20 mph, not even close, not sure where that came from. Originally I was talking about very steep downhills, 32- 36mph and that it would be nice to have a bit higher gear. As nicety, wondering if it was possible, but we have been through all of that.

I am proud to report that with my LBS being so backed up I figured out how to replace my rear cassette and chain and got all of that up and running this weekend. That was a cool first for me.

Thanks everyone for the education.

SethAZ 

Awesome news! Congrats on learning and doing this stuff. It's funny how this stuff can seem so mysterious to some folks, but if you dig in and learn it things like swapping cassettes, cutting down chains and using master links, etc. isn't that complex nor difficult. A couple special tools like a chain whip and that special splined driver (whatever it's called for loosening/tightening the cassette lock ring) and you're all set. It's liberating not to be bound to paying the LBS to do simple stuff you can easily do yourself.

As an aside, in some of my rides recently I've ridden over to this one route that takes me through some low hills maybe 7 or 8 miles from my house specifically because I like having these short climbs included in my longer rides. The descents down these fairly shallow climbs have given me a good opportunity to examine the tradeoffs I made when I chose to "downgrade" my 50t large chainring in front to a 46t gravel bike chainring. Combined with my 12t highest cog in the rear by the time I hit the upper 20s I'm already in my highest gear on these descents, and how fast I can actually get is limited then to my spin-out cadence. I wouldn't necessarily always want to have to be spinning 100+ rpm just to be able to contribute a little power to the effects of gravity on my descents, so this is unfortunate. Viewed in context, however, where 99% of my riding is in flat territories where I'm usually limited to below 20mph on a cruise or maybe into the mid-20s on a short and above-threshold effort or even a sprint, the benefits of this tradeoff are totally worth it. But yeah, when I'm in hill country there are certainly consequences to my gearing, and not everyone would agree with that tradeoff.

Archinutt

SethAZ - It is cool to do this stuff. And I really should for as long as I have been riding. It's only because of having a bit more time (when I would be driving or going to volunteer type stuff) I had time to block out to learn how to do it. The cassette and chain took me a very long time given the research and going slow and careful. Like so many things, If I was to do it again it wouldn't take me any time at all. Both of my bikes needed a shifting adjustment too. I was fine on the rear derailers, but I just couldn't get the front derailers to act right. I had cry uncle and call my neighbor for help before I did too much damage. He isn't as familiar with the new shifters but got them both working and we had a great visit. (I paid him in recently smoked pulled pork)

I took a 20 mile ride tonight on a favorite trail and all worked out well. Based on this post I am trying to spin a little faster, or at least be conscience of it in the long run in a way I wasn't before and see how that improves things. 95% percent of my rides are solo so there isn't much to compare to. I work full time and then have an art studio and do watercolor commission and teaching in the evenings so my schedule is sporadic and hard to schedule regular rides with folks.