Thread: How f'd is this bike?

Friend has a Giant Anthem, bought replacement XT bottom bracket at local shop, and they installed it. A month goes by, he notices that part of a plastic dust shield on the BB is missing, so brought it back to shop. They didn't have any Shimano BBs in stock, so they put in a Race Face BB with his XT crankset. Resistance when turning the cranks was *very* high -- shop told him it would wear in as he rode, but IMHO it was much higher than it should have been, simply from new seal drag. He rode it, and after a couple rides it did improve.

He brought it by my house yesterday, since he noticed this uneven gap at the BB spacers when he had his bike flipped upside down to fix a broken chain on the trail. Here's what we saw:



Looks to me like the BB was cross-threaded and forced into the frame at an angle, which would explain the incredibly high resistance when turning the cranks when that BB was first installed. I suggested that he go back to the shop and be present when they remove that BB, and see what the threads look like when the mechanic removes it.

I think the BB shell is cross-threaded and that frame is permanently trashed. Your thoughts?

(also, that BB shell should have a screw in it to plug the cable guide hole, and it's missing...)

It can probably be re-threaded, if the shop is good and has a tap for that... That hole is not plugged on mine, or others bikes.

the shell can probably be rethreaded but I wouldn't take it to the bike shop that fucked it up. That being said, I think they should refund him at least the labor costs and the costs of the parts. I think they should also give him a new bb of his choice for free for his troubles.

this is why you should NEVER flip yer bike upside down when doing trailside repairs

i'd have that shop by the ballz for this. i'm a shop guy. this is inexcusable. so much shoddy bike work gets done by shops out there.

i'd get a new frame outta of it. if i fucked up that bad, you surely would be getting what you want, and if that means a frame, so be it.

rog

Originally Posted by Yukonrider

It can probably be re-threaded, if the shop is good and has a tap for that...

Originally Posted by Gman

the shell can probably be rethreaded but I wouldn't take it to the bike shop that fucked it up.

If re-threaded (run a tap through and hope the original threads are still OK), isn't it going to be more prone to stripping out in the future? There's only so much metal there, and it's aluminum, so not really the strongest material to play with.

Originally Posted by El Chupacabra

If re-threaded (run a tap through and hope the original threads are still OK), isn't it going to be more prone to stripping out in the future? There's only so much metal there, and it's aluminum, so not really the strongest material to play with.

dood, they fucked up. you understand that right? just get a new frame.

rog

Originally Posted by icelanticskier

dood, they fucked up. you understand that right? just get a new frame.

Understood. It's not my bike though, so who knows what they'll tell my friend when he goes back to the shop with it. It's a Giant frame, and the shop that messed up is a Giant dealer, so that might work out OK for him.

And this is why my own bikes never see a shop for any service work.

gotcha^^^^^^

rog

Does the shop carry Giant? Either way you need to take it apart to see if/what was damaged.
You might also consider taking it to the shop and having them note it, ride it the rest of the season and dealing with it in the winter if everything else is holding together vs. not having a bike to ride for a month or two...

I wouldn't take it apart. I would take it to the shop and watch them take it apart.

There are so many of these threads where we get the pitchforks out. I think the best practice is take the mistake back to who did it and get their opinion. Some of these mistakes are pretty embarrassing (this one) and shops a lot of times will take care of the customer because of that alone. I'm sure the resistance was bad and the shop telling you it's normal only makes them look worse. You can always go for the throat later but see what they'll do to fix it before asking for anything.

It might be able to be tapped but that's a pretty big f up to ever send something like that out, especially when the customer inquires as to why it feels weird.

Cross-threading a bottom bracket like that would take a shitload of force - I removed a couple like this when I was at a shop. Whoever put it in either knew what they had done, or didn't know and should be working on customers bikes. Either way the shop should know about this.

I'm with Cman up here ^ take it back, let them offer to make it right. If they don't, then freak out on them

Sounds like the first install was botched, the weird load broke the bearing cover. The second install could have felt normal if the threads were already screwed. Its probably fixable. I would have threads cleaned up and torqued to spec. If they pull out your bud should get a new frame. Bummer its 68mm shell, less threads engaging with those spacers.

How the fuck do you even do that?

Another option is to permanently connect the BB cup to the frame, in it's correct orientation. This could be done using JB weld, or even better, finding someone with the ability to weld aluminum. The advantage of external-cup BB's is that the bearings are replaceable without needing to replace the cup. I've done this on a single speed cross/gravel bike of my own, and it's held for two years with no issues.

I might only pursue that option if the shop won't stand behind what they did, and doesn't replace the frame. Tapping the threads could very well leave very material for the cup to be held in place, particularly if the tap were to jump from the original threads to the newly-created crossed threads.

Originally Posted by willmtbike4food

Another option is to permanently connect the BB cup to the frame, in it's correct orientation. This could be done using JB weld, or even better, finding someone with the ability to weld aluminum. The advantage of external-cup BB's is that the bearings are replaceable without needing to replace the cup. I've done this on a single speed cross/gravel bike of my own, and it's held for two years with no issues.

I might only pursue that option if the shop won't stand behind what they did, and doesn't replace the frame. Tapping the threads could very well leave very material for the cup to be held in place, particularly if the tap were to jump from the original threads to the newly-created crossed threads.

this. or re-thread and stick in a DH cup on that side - longer threaded area. quick fix until he can either get a new frame, or whatever. hell, that might work just fine for the rest of the life of the frame.

I get pissed off when I read threads like this. Yes shops make mistakes, but when they noticed the drag they should have spend the extra 30 seconds to take a look & realize the screw up.

Originally Posted by Conundrum

I wouldn't take it apart. I would take it to the shop and watch them take it apart.

There are so many of these threads where we get the pitchforks out. I think the best practice is take the mistake back to who did it and get their opinion. Some of these mistakes are pretty embarrassing (this one) and shops a lot of times will take care of the customer because of that alone. I'm sure the resistance was bad and the shop telling you it's normal only makes them look worse. You can always go for the throat later but see what they'll do to fix it before asking for anything.

That's what I suggested to my friend (again, this is not my bike). He is going to take it back to the shop during the week, when it's not as busy as on weekends, and watch while the mechanic disassembles it.

Originally Posted by El Chupacabra

That's what I suggested to my friend (again, this is not my bike). He is going to take it back to the shop during the week, when it's not as busy as on weekends, and watch while the mechanic disassembles it.

Until then, this is just one mechanic who did something stupid and didn't want to own up to it. I bet he ends up with a new frame out of this. I'd want a new bottom bracket as well, as there is no way that thing is going to seat right after being torqued like that!

Originally Posted by Mickey O'Neil

Proper fucked?

Originally Posted by El Chupacabra

And this is why my own bikes never see a shop for any service work.

X eleventy million

Originally Posted by willmtbike4food

... or even better, finding someone with the ability to weld aluminum.

This is a horrible idea, FYI.

Don't weld aluminum. It looses its heat treatment, which is bad. It is not economical to weld and then re-heat treat.

Originally Posted by El Chupacabra

That's what I suggested to my friend (again, this is not my bike). He is going to take it back to the shop during the week, when it's not as busy as on weekends, and watch while the mechanic disassembles it.

I'd make a point to get the shop manager/owner in the loop on this ASAP. A good one will want to get involved, they don't want their shop name getting thrashed by a mechanic(using that term very loosely) that is incompetant and lazy enough to force a cup on that crooked and making no effort to at least back it out, clean things up, and put it on right.