Joe Remi

It's on a fairly new and not super low end Dahon folding bike, but what a lousy design. It's cup-and-cone, I got the left side adjustable cup off fine but this fixed side is stuuuuuuck. The closest tool I could figure out for it is Park HCW-11 but I got nowhere with it even with washers clamped down tight over both sides (I'm turning clockwise to loosen). Anybody got a better idea?

Andrew R Stewart 

Assuming you can't locate the proper tool a Kingsbridge type fixed cup vise should work.



Older shops that had a service focused business might have one, or the less able but still worth trying UBI version. Tool Tips--Bottom Bracket Cups (sheldonbrown.com) is a home made version. Andy

oldbobcat

You might be able to fashion a fixed cup vise with hex nut that fits snugly into the notches in the cup socket fitting. Fasten to bolt inserted from inside to prevent slipping.

maddog34

have you tried contacting the source of the Problem? they may have a dealer in your area that will have that ridiculous tool... https://usa.dahon.com/pages/contact-us

there may also be a two prong Freewheel Remover that will fit that badly thought through choice of bottom bracket design. BMX shops usually have a plethora of odd Freewheel tools around.....

AND have you tried turning it the OPPOSITE direction? This will, sometimes, break loose a stuck BB cup.... And there's a chance that BB is a French or Italian thread... Dahon makes Odd Design choices... this we already know!

might i ask.. WHY are you wanting to Remove that cup? is it damaged? rusty? if not, just stuff a shop towel in there and clean it on the bike.. regrease with a grease gun or dabs on a big screwdriver, reassemble and ride.... it LOOKS ok from the outside... just sayin'

my advice is: In the future, avoid Dahon.

Joe Remi

Thanks for the bike advice but I've worked on a dozen Dahons, most have a normal BB I can easily remove. This is the first weird one.

Joe Remi

It's BSA, the lockring that was on it unscrewed clockwise. I'm removing to put an ISIS-spline bottom bracket in that mates to the 155mm cranks I want to use.

I guess I'll try the bike shop tomorrow, they may figure it out. I'm just not used to failing at these jobs, I usually find a solution. So far not so much!

Kontact 

Have you contacted Dahon? There might be a cheap cast tool they can send you.

Andrew R Stewart 

I wondered about the cup's retention to the shell as I didn't notice any lip or flange that would bottom out against the shell's face. With the lock ring removed one would hope that the cup would easily be able (tool independent) to be unthreaded. However this not being the case makes me wonder about the condition of the shell's threading. Heat distortion, poorly cut (or unchased) threads or too much paint inside the shell are common reasons why an otherwise "unlocked" cup might not freely turn in the shell. So, if you are able to remove the cup, I suggest that you have the shell chased (and faced) with proper tools. One more reason to have a good relationship with a good shop. Were you close to me I would help out and this would be a fairly quick job, excluding other unknown issues.

Another poster suggested seeking a DaHon dealer. I was one briefly back in the 1990s (or was it late 1980s?). But the slow sales, the long build out of the box time required to make the bikes be of shop grade function (or as close as we could get them to be) and the lowering of quality we say over the couple of years we dealt with the company led to our discontinuing selling them. In the 2ish years we might have sold 5 or 6 bikes. But my shop was known for service and repairs more than bike sales. With that reputation and previous dealer status we say a few come through our service shop every year after (until 2000 when i close up the shop for good) and sad to say but the quality thing didn't seem to get better. DaHon began to sell direct to consumers and to offer their bikes as promo items for other industries' spiffs to their employes. needless to say the lack of feedback to the company didn't do any good WRT improving quality. Andy

Joe Remi

Andy, I think it's likely the cup was cross-threaded in there by a big machine and I may be looking at more drama if I ever get it out. New plan! The bike is near-new and most of it is higher quality stuff than this ridiculous bottom bracket (and the crappy crank I removed) so I stuffed more grease in there and put it back together. I have a square taper crank I can use, I'm going that way with it.

Dan Burkhart 

Just spitballing here, but looks like a hex head of the appropriate size bolt would mate to the depression in the cup if the spindle were removed. Thread on a nut and you have a removal tool.

Andrew R Stewart 

Often a cross threaded in cup will show by its lock ring (or flange) not seating flat against the BB face. Also a good eye can see the cup's thread entering the shell with two threads and not one per circumference. Another also is that a cocked cup will often result in a tight but loose bearing adjustment, Any of these possibilities happening? I do agree that there's the place for a "stop now and just tolerate the situation" choice. Andy

Joe Remi

Nope, all those check out fine. I guess it's just in there really tight and I haven't found or created a proper tool yet. Despite its cheap heaviness the thing works like a proper cup-and-cone BB so I might as well use it for a while.

I bought the bike as an around town grocery getter that will be easy to store, all it needs to do is meet those needs while not being a huge heartbreak if it gets stolen locked up in front of the market. I've been using a MUCH nicer bike for this and I needed a different plan.

Joe Remi

Square taper cranks on the stock bottom bracket. Solved!

Andrew R Stewart 

so, did the cup come out? If so how did you do it? Andy

Joe Remi

Nope. I put more grease in there (new Dahons don't come with much), put a square taper crank on and everything is good. It wasn't the original plan but it worked out well enough for what I need from this little folder.