Hi. I have 2 questions.

I run a 10s Deore drivetrain. My cogs are 11-42 and chainring is 30T round. My current chain length is 108 links which works fine. I am upgrading my chainring to a 32T oval. I want to know what will be the required chain length I must use? If it was 32T round, I would use 110 links based on a chain length calculator. But now, it's oval. I don't see any calculator including oval chainring which is a different design. So, I cannot determine what will be the required number of links. Will it be 110 links as I would use for a round chainring?

Second question on bike washing. I used Decathlon bike cleaner. But I see I'm wasting money. I used bathing soap in water before to wash my bike. It worked great. So, do you think any bathing soap or dish washing detergent are good to clean bike?

EDITED: I run x1 drivetrain.

Thank you.

Q1: See this. TL;DR, the chain ring shape (oval v. round) shouldn't affect the chain length, just the number of teeth.

Q2: a few drops of dish soap in a gallon of water will work fine. Just make sure to rinse the bike really well, as some dish-soaps are rumored to have salts in them to aid in grease removal.

You may not need any more links, since 2 more teeth means you "need" a half inch more chain, and if you have that much slack in the system then no more chain is needed. Remember, only half of the chain ring (or cassette cog) is engaged at any time.

In the US at least, Dawn dish soap is the go-to brand.

I use car wash soap when I want to clean my bike. It is formulated to not be harmful to paint

My method of knowing how many chain links to use depends on how the chain looks when I shift it to "small-small" gear combo. That's the 11t gear in the cassette and the smallest size chainring (unless you're on 1x drivetrain).

If the chain isn't slack, I add 1 link and so on and so forth until it's slacking just a little bit. That's how I do it to maximize the number of chain links possible so when I shift to the 42t cassette for example and the biggest chainring, the chain won't be too tight and the rear derailleur doesn't look like it's reaching for it's soulmate.

Thanks, I guess, I will add a link, thus, 109 links. And I am not from the US, but all dish washer soaps or gels will be OK I guess. What about body soap?

Post mechanical questions in the proper section...oddly enough it's called 'bicycle mechanics', not here in GD.

And I would never use soap of any kind on the drivetrain, you'll need a degreaser. Dawn works great on the rest of the bike.

Why not use two threads for two totally unrelated topics? Is the internet too limited for that?

I really doubt body soap will clean off the road gunk and grease off a bike.

But your bike will smell marvelous.

John

To increase the chain length, you need 110 links or 55 inches. No such thing as an odd number of links.

It might help to know how dirty your bike gets. As well as what type of grime it is. I haven't washed a bike in many years. Not since my kids grew up and quit riding their bikes in the mud.

I suppose I might deduce from Deore, that your bike is a mountain bike. But I know many that have mountain bikes and never ride them off pavement.

I just use some of the moist towelettes that come in a big tub or jar. After using one or two to wipe the frame and other parts, the towelettes then get the grime off my chain, chainrings and cogs. Albeit not super easily does the gunk come off, but well enough that I don't need more expensive, hazardous or just more trouble to mess with to me.

It is a lot easier to take a pair of links out of the chain if it is too long than to put a pair back in after you cut the chain too short. Start with the largest number of links you think is ideal and work backwards until the length is correct.

A “degreaser” serves basically the same function as “soap” in that both allow for a nonpolar substance…oil, grease, etc…to be dissolved in a polar substance to a limited degree. Bar soap would probably not be the best choice because if its solid nature but body wash, Dawn dish “soap”, and Simple Green (as well as other “degreasers”) are very similar in nature and composition. The surfactants used in all of the liquid detergents are of a similar molecular structure.

That said, none of the water based surfactants are as efficient as using a nonpolar solvent for degreasing. Even with a very high load of detergent in water, there is only so much grease that any of them can dissolve meaning that gallons of water and detergent is needed to do the same work as a cup or so of mineral spirits, for example.