Gearing Question

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So my current quest is a Nel Lusso based ....... Beach Bum Klunker named Nuthin's Easy. I still need to disassemble and grease the rear hub but the gearing seems a bit tall. Hills are not really a factor. However, 1. I'm an old man and. 2. I typically use my klunkers for serious long rides. 3. It may at some point use Maxxis Hookworms. The easiest fix of course is a smaller ring up front. I have a couple 20" BMX bikes as donors. Will one of these bolt up to my current cranks? The end result will be something like 36/19. I do most of my riding on pavement. I have little interest in hauling ... but don't want to spin uncontrollably either. Looking for something I could jump on and ride 20-50 miles an not feel like I'm pulling a trailer. How small could I go in the front using the stock cranks?
 

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I run 34/18 or 36/18 on my hard tails and can spin all day long comfortably. Flat as a board around my parts so hills are not in the game plan. Crank length, tire pressure are things to consider as well

36/18 on my bike from the last big build off

IMG_20210906_082542643_2.jpg
 
Perfect, that formula is the bee's knees. My donor rig is a 32t chainring and crank off one of my junk BMX bikes. When I do the rear hub just slap a 15t cog in the back, new chain and presto! This combination puts me just a tad below 55.5 so it should be good to go! Thanks brother
 
The Holy Rollers you have on there roll better than the Hookworms, The hookworms have a softer compound and are made to be more sticky for skate park applications.
I do really like the Holy Rollers. They don't have a lot of miles on them and the plan was generally to ride these into the ground before shopping for Hookworms. You wouldn't recommend Hookworms?
 
I do really like the Holy Rollers. They don't have a lot of miles on them and the plan was generally to ride these into the ground before shopping for Hookworms. You wouldn't recommend Hookworms?
From what you described the intended use to be and the importance of less rolling resistance, I would not recommend Hookworms. If you were to be riding smooth concrete skateparks and going vertical or beyond, the Hookworms would be a far better choice.
 
Your 32/15 on 26 x 2.125 tires puts you at 55.93 GI. That should be a big improvement over what's on there now, looks like a 44/18, which is 64.07 GI.
 
The BMX cruiser bike guys have a starting ratio for the 26 inch wheels: 2x+2. That means that the big cog has twice as many teeth plus two, as the little. 32/15 fits the equation, should be a good medium gear, not that hard, not too spinney.

*I've got an entire file on my phone for gear ratios, have mapped and charted all the gears on a couple of my bikes, but I still don't understand gear inches. Wildcat's math is a much higher grade than mine.
 
Math? :rofl:

I found this calculating site that gives all the answers on gearing. Right down to the exact tire size and you can see your cadence at certain speeds. The lower ratio is pretty good for me, on road and off. I don't need to go fast and I'm officially a senior citizen now. I used this when I was trying to figure how to get a normal gear and a low gear from my Sram Auto. It has a direct gear and 138% step up. I just needed a smaller chain wheel and a 42/19 works fine.

https://www.bikecalc.com/gear_inches
 
Your bicycle uses a one piece crank. Check the BMX bikes to make sure they use the one piece design. One piece crank sprockets in all sizes are easy and usually cheap to find. There are huge amounts of bicycles with one piece cranks and they may be the most used crank on American bicycles. I'm an old man and love medium length rides, 20 to 30 miles.
 
3 speed Nexus coaster, if you can find one. Easy to adjust, good coaster. Front brake incase a chain snaps. Gravel king smoothie, or similar that come in 26. This type of tire is flat resistant and roll well. I don’t think Panaracer gravel kings come in 26, but others make a similar tire in 26.
851A045B-DF15-4187-81E7-C9F2B929561F.jpeg
 
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How small could I go in the front using the stock cranks?

Smallest sprocket I've seen is a 22t.

Installing a smaller sprocket usually means taking a link or two out of the chain. Putting on a bigger cog on the hubk usually means a new chain. Adding links to existing chains is a pita. The pins and holes in the links for each brand and model of chain are microscopically different and most aren't interchangeable.

Another option is longer crank arms. Those work better for taller riders or going up hills. Gives you more leverage when you need it most. There are some nice bmx cromo 1 piece cranks in various lengths.
 

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