Is this a “fiddle with it with my bike friends” issue or a “take it to the shop” issue? I was already planning on bringing it in for a full tune and bath for the end of the season, I’m inclined to just let them take care of it but my friends with a few more years of biking under them are eager to do it themselves….bike is a Poseidon Ambition X, still under warranty if that’s relevant (I have a feeling it’s purely a maintenance/service issue but if I’m wrong that could be useful!)
Thanks all.
First year cycling. 1500mi on the year and just completed my century. Now my bottom bracket(?) is loose(?)
byu/thesneakernet inbikewrench
by thesneakernet
11 Comments
😱😱😮💨
So it seems the threads in the bottom bracket shell of the frame are toast.
You’ll need a repair bottom bracket that screws into itself.
Shop for sure
It’s fucked. Most likely threads on a frame are stripped, it should not be this loose even if not tight.
You might try to examine it by yourself and remove the bottom bracket. If frame is somehow fine – then just install a new bottom bracket. If not – probably a repair shop can help. Or they will tell you that you need a new frame/bike.
“take it to the shop” for sure.
The threads on the bike might be bad so definitely take it to a bike shop so they can chase the threads with the proper tool if needed.
I broke the rear triangle on my Kona entourage and 5 years after the warranty ended they still replaced it, most bike companies are filled with fellow bike people, so I can’t imagine them not helping out!
Time to replace! I’d also have your frame checked because the shell seems loose, not just the axle. Might be an LBS job instead of a home repair.
That’s a cartridge bearing that is screwed into the bottom-bracket. The whole cartridge is shifting inside the frame, despite the fact it is screwed all the way in – so the threads of the frame must be damaged, which means a new bearing cartridge won’t be able to screw in properly either. If the frame is special/expensive there are ways to fix this, but they’re going to involve at least one of:
– shimming and using a pressfit bearing
– oversize bearing cartridge
– brazing and re-cutting threads
– using a screw together bottom bracket bearing that doesn’t rely on the frame’s threads at all (and probably a new crank to fit it)
Oof, if it was bought new you might be looking at a warranty claim, bottom brackets like this shouldnt do this after normal wear, worth reaching out to the shop you bought it from and the manufacturer. Assuming thats the original bb you should get a new frame
Warranty? Make a claim?
Finding good, quality Square Tapered Bottom Brackets these days is: daunting. During the pandemic. Parts were scarce. Shimano, in their infinite wisdom. Decided to put out the UN300 BB. Which in my opinion is complete and utter GARBAGE! There I said it. Anything Tourney is fucking garbage!!!
Won’t last a winter. The plastic seals will allow salt, water and road grime get into the ball bearings. Try and find a UN26 or UN55. Good luck on ebay and get fleeced!
I’ve got a UN55 on my Marin Fairfax 1. Put on in 2014. Still works. UN300? Craps out in 4 months of use.
JB weld that shit and ride on