Need a 40 or 42 T set up, cheap
 

Working on a fast and light commuter. Good weather only, no fenders, no rack, might go with a frame bag. I have an older Japanese steel frame and most of the parts. Looking to do a 1x9/10 drivetrain. Drop bar and rim brakes too. What would be the cheapest /easiest way to get a 1x chainring? I have a bunch of square taper cranks. Some of the older 39/53 road chainring set ups and some mt 9 speed triples. Can you use just the inner on an older road double? Seems the outer of a 9 x mt triple will not yield a good chainline. Run the 42 in the middle position? I realize for $100.00 or so a nice track or mountain single can be had.

I have a sugino 5 bolt 130 bcd crankset with a 42t ring for my 1x(used to be fixed, then 1x7, now 1x10) setup. Universal cycles has just the crankarms so then you could buy the chainring separately and hopefully keep your total price down (depending on arm length) vs buying the whole crankset w/ 48t ring included. It's actually a 2 ring setup, just use the outer position to run it 1x

Yea,the Punch cut Sugino Chainrings are low cost.
the Alloy is softer to allow all the teeth to be cut in one stroke.

Middle of a triple should be fine for a single ring, if the Triple chain ring crank is set up properly..

Well, big to big can be a bit of a problem.

running the inside of a double, or middle of a triple should be OK. Ideally a 42t single speed fixed gear setup would work but those typically require a 8speed chain. The benefit of using a singles speed crank is that the chain ring is designed not to have the chain shift off of it. I have much less chain drop with a single speed chainring than with one designed for shifting.

Running a 1x9 or a 1x10 drive train. So yes, no shifting ramps would be ideal. Nw makes some. Just need to find the right bcd.

I think you could use either side of a double square taper. If you want to obsess about chainline you can get a BB 5mm longer than recommended for the double if you're using the inside or 5mm shorter if you're using the outside, but really I think it would be fine either way. You may need shorter chainring bolts.

Lot's of vintage cranks had 42T rings with no shift ramps. You ought to be able to find one for cheap.

Good thoughts, thanks all.

Contemplating a similar project. Best bet is to scour eBay for the right size.

Surly Stainless steel are going to wear longer, so though initial cost is higher

the wear/miles usability will be longer , and they're Flat, so can be flipped over
to further double the wear life.

@Leebo, what crank are you using? Specifically, are the chainrings removable, and if so, what is the bolt circle diameter? I may have a chainring I can send you for cheap.

Still working on sourcing parts. Will keep that in mind. ^^^^

We turned my wife's old Peugeot into a 1x 9. Used the small chainring which I believe is a 40 tooth. Matched it to an 11 -32 9 speed cassette and older Tiagra medium cage derailleur. I did it with the help of my LBS. works really well. The easiest gear is small enough to handle most of the hills we ride regulArly, most of which aren't too steep.

I recently completed a Bianchi 650B conversion and set it up as a 1x11. I'm using an old Shimano 600 crank (130 BCD) with a new inner Shimano 39t chainring. It works great. I'm using an IRD 103 mm BB with the ring mounted in the outside position for an almost perfect chainline. I may change to a 42t ring, but with the 11t small cog, 39X11 is plenty high for my aging legs.

I'm running the inner 42T Biopace chain ring that was stock on my bike. I currently have it set up as a 1x9 running Deore rear components and have not had any issues yet.

I am converting my CrossRip to a flatbar 1x commuter and I have Shimano 105 cranks and versus getting a new crank, I bought a $80 Wolf Tooth chain ring. Got the 42T and will run the 11x42 in the back.

USAmade 110/130 fits both 110 and 130 crankset, so you can re-use one you have already.

https://www.amazon.com/USAmade-Mount...made+110%2F130

https://www.amazon.com/USAmade-Mount...made+110%2F130

https://www.amazon.com/dp/B01BMZW914...=IUWWQKECM9M6E

I purchased a 44T for a 1x9 commuter with a 12-36 cassette; suits my riding style and commuting terrain. I have a 2x8 on another commuter with 52/39 and 14-32 cassette. The two have almost exactly the same top and bottom ratios.