Hi All,

by replacing the BB, I damaged the crankset on my BD Atroz 1x9. Now I have to replace it too. The problem is I am not sure what will fit.

The BB was square taper, no-name, 73x113. Replaced it with SHIMANO BB-UN55 Square taper Bottom Bracket 73x113.

The original crankset appears to be Lasco, FM682R G-1 175 (that's all written on them)

Bought SHIMANO M361 Hybrid Crankset (Black, 175mm X 42/32/22T)

Also decided to replace the chainring with CYSKY Narrow Wide Chainring 104BCD 32T 4 Bolts Bike Single Chainring for 9 10 11 (original was 32T, no name)


After removing the rings from Shimano M361, and replacing it with Narrow-Wide, trying to install and it does not fit properly. First of all, it goes way too much inside the BB, to the point that it touches the frame (with the 4 parts where the small chainring was attached). Even if I shave out the 4 pins into which the small chainring was attached to, still i have the filling that there is too much play between BB axel and the crankset and it goes too deep into axel. I measured the square diameter on the new crackset and old one and the new one is slightly larger; which does not make sense to me.


Please help with what crankset would fit properly for this 1x setup.

Pics:

1st: on the left the new Shimano crankset, right the old one

2nd: original crankset on the bike.


Thanks!

Is putting a BB 73x118 and using the the Shimano Cranks that I bought a possible solution? Any other options?
I am lost.
thanks!

Buy a different Bottom Bracket. MEASURE how many mm you want the ring to come out, double that and buy new BB.

thanks. I am not sure what should I double. I just measured 10.5mm = the distance from the frame to where the chain ring should be (same distance from frame to the chain guide roller).
The frame width measures 73mm.
Do I need to measure something else? thanks!

update: I found now this info on the cranks:

Shimano Acera 7/8 Speed Crankset features many of Shimano's features that can also be seen on higher end components. The patented Hyperdrive system will provide quiet, easy and trouble free shifting. Available in two arm lengths and two gearing options. Choose the 22/32/42 option for standard mountain bike use and the 28/38/48 for taller road like/touring gears. Also available with a chain guard.

SPECIFICATIONS

• Rings: 22/32/42 or 28/38/48
• Spindle Interface Type: Square Taper JIS
• Spindle Length: 122.5 mm
• Crank Arm Length: 170mm or 175mm
• Chainring BCD: 104/64
• Bolt Pattern: 4-Bolt
• Chain Compatibility: 7/8-Speed
• Pedal Spindle: 9/16"
• Color: Black
• Crank Intended Use: Mountain

Does it mean I need 73x123 BB?
thanks again.

You bought a new crank. Bottom bracket goes with the crank, not the bike.
MEASURE
Do you know how to measure chainline? Look it up.

Next time buy the correct tool to remove your crankset.

thanks trailangel for the info.Yes, I measured, although not sure if correctly. I ordered 122mm one. Hopefully it will fit.
I have the correct tool. Unfortunately, the thread from the crankset got ripped off while trying to remove it. Yes, that was unfortunate, and the only choice for me was to use a puller with three legs. Having 4-bolt crankset, mounting the puller properly was not an option, and the crackset got demaged. All, that is the past, now I am figuring out how to get out of it.

OK, the chainline is 47.5, which could be easily determined from the two numbers I provided = 73/2+11= 47.5.
I am still not sure if the BB UN55 73x122 and the SHIMANO M361 Hybrid Crankset will give me this chainline.
Yes, I looked at https://www.sheldonbrown.com/bbsize.html adn tried to find the tech specs for this BB and Crankset, but still not sure.
Could please anyone confirm if this combo will work?

final update, maybe someone would find it useful in the future: BB UN55 73x122 and the SHIMANO M361 Hybrid Crankset
thanks for those who helped, although a direct answer would be more appreciated rather than playing smart and sending to read how to measure things.