sdmc530

So short of sort of purpose made chain keeper would a non functioning front mech do the same thing?

Building my 11 year old sons first road bike and using 1x system. I have a 2x crank set on the bike just using the smaller chainring. So the large chain ring acting as a guide on the outside but nothing on the inside concerns me.

I know what your all thinking, make it a proper 2x system and don't worry about it. The problem is my son doesn't want a 2x and the small to large front chain ring jump would be big for the front mech anyways. AND the parts I have on hand without buying more stuff is always a bonus. I am not even sure what gearing he will have yet so a narrow wide chainring is in the future as soon as we can figure out the proper front chain ring size but for now I am looking for some cheaper temp options.

Go ahead and beat me up too, I can take it

Seriously any thoughts would be appreciated.

FYI the road bike is running a sora set up.

CliffordK

It might not hurt to trim all the teeth off of the outer ring to use it as a bash-guard. That will also help prevent things like pants from getting caught on the ring.

The front derailleur may help some. Or, it is quite possible that he won't drop the chain on the inside when not shifting. So, leave it off and see if it actually is a problem.

If the inner ring does become a problem, then look for a 1x chainring.

Darth Lefty 

You can put the FD back on and adjust it so it won't rub. Maybe.

Kid bikes commonly come with inexpensive 3-piece cranksets with a permanently mounted 36 tooth ring. You could find one of those - maybe ask in a forum like the one on MTBR because the "serious" dads are throwing out oem components all the time. They sometimes have some kind of simpler chain retention like a bash guard.

The Specialized version has a top chain guide and a bottom idler. It's stout. I took it off my kid's 20 inch bike because he's a pretty timid rider and it all weighs about a pound. He hasn't dropped the chain riding but it's come off a few times slinging the bike around.
https://www.specialized.com/us/en/hotrock-24/p/184500

The problem I see with a "full" 1x setup is that you've started as far from that as possible. All the road/gravel 1x controls are for hydraulic discs and the newer longer cable pull. There's no gravel equivalent of Sora yet, for example, and if there ever is it might not have a 1x or clutch option.

sdmc530

I didn't think of cutting off the teeth of the non used ring, I am going to do that! Nice tip.

I am going to not try the FD, seems like not so great after I think about it and the couple comments on it.


I will probably go with nothing and see if it even is an issue as you suggest.

sdmc530

My son has that hot rock but the guide won't fit because I have a 2x front ring set up, I did try that already. The 1x not for a road bike is something that seems like a whole miss in the market IMO. Being in a very flat state I would use one too on my road bikes but not going through all the work when all my 105 systems are already golden.




to be clear, the end goal is to get a narrow ride when he decides what size he likes best. this is all temporary issues that hopefully won't be issues in the end.

thanks

CliffordK

What crank length are you using?

165mm?

zandoval 

He's eleven years old... He can take it, learn it, and out grow it...

Don't do anything special. It won't be long before he is on his bike and you on yours and he is squashing Ya like a Bug!I

sdmc530

He is up to 152mm

He tried 160 but there a bit of a stretch yet so 152 is where his most comfortable at right now. Will use this until we get to 160's range. The only reasonable set of 152 was on a triple set up. Its good but not perfect yet short of of a narrow wide ring.

sdmc530

I look forward to this and fear this

I will leave it be I think and see how it goes now.

I built this the way I did so when he out grows the frame size and cranks I can strip this frame of most everything and upscale it to the next size frame. There is a good use to have a box full of old parts and crap sometimes. Was pretty handy for this project.


progress so far...... well as of last night, wheels got put on today so we are at least using the mech



Paintjob inspired by star wars, cyan and pink what he wanted.

Digger Goreman

In the interim of switching my old Trek mtb from 3x to 1x, I rode the bike with the FD limit screws dialed to the middle and left the FD on as a chain keeper. No issues, though noting that I RARELY leave the roads and MUPS.