Hi Guys,

I really hope you can help advise me on a BB problem I have.

I purchased a bike frame (bankrupt stock) recently which was advertised to have an English threaded bottom bracket.
I purchased a Shimano BB-R60 Ultegra 6800/105 5800 Hollowtech ii English Threaded unit for this but when I got to fitting it, it just fells into the BB shell – too small !
I then got the same BB, but this time Italian threaded – this time it screwed in about a turn and a half and then stops – I haven’t forced it further for fear of damaging the threads of the either the shell or the cups.

So, I’m at a loss really and was hoping with your wide experience you might be able to point me in the right direction…


Thanks in advance,

Jim

Here's a helpful page for you, scroll down about 1/3:Sheldon Brown's Bicycle Glossary Bo--Bz
Maybe a Raleigh?
Assuming it's old enough I suppose.

Would help if you could give the name/model of the frame / photos

Of course, it's one of these:

SAB Mod: "MASTER"7000 Series Road Race Frame 50cm Silver Damaged Headtube | eBay




Alu frame with a carbon rear triangle.


Thanks

In the first place, would be asking PX either through the ebay contact seller, or just giving them a call. You may need to take it to a LBS to have the threads chased, but would be looking for a specialist one, as Italian thread cutting tool is very specialist, rather than a BSA/English which most shops should have.

Going by this https://www.planetx.co.uk/i/q/FRSABC...luminium-frame which looks to be a very similar frame, the BB is Italian thread

It happens all the time that brand new frames have threading that needs to be chased before a bottom bracket can be installed, even on high quality frames. It doesn't take long to do, but you have to have the correct tool to do it

A 24tpi internal thread restorer will save on the cost of a chasing die or trip to the lbs if the problem is merely slightly damaged threading.

Take care when chasing threads, or deciding whether to do so. It's real hard to put the material back on the shell after Seriously, an experienced person should be consulted before any cutting tool is applied to a frame. Andy.

I already contated PX who told me that basically they inherited a load of these frames when SAB went bust.

He went on to say that the warehouse staff basically take a quick look, and stick up on the web what they think the BB, headset etc are - but they are often wrong.... not the greatest customer support TBH, but hey it was dead cheap so I can forgive them that.


The measurements of the BB certainly looks like an Italian thread (from memory 70mm across and 36mm diameter), but I just don't understand why on both sides I get about 1 and bit turns before it become so stiff that a wrench would be required to continue screwing it in, I've done a couple of BB's in the past and these have screwed in almost all the way under finger power.


Going the local bike shop would be my next course of action, but I didn't want to waste their time if it was something I could fix myself.

That's half the fun of buying from PX, had some great customer service from them and some pretty terrible as well.

The first step before any cutting or chasing should be to confirm that it is indeed Italian - 36x24 - threaded. One solid clue is whether both sides are RH thread. You can do that by eyeball, or by tracing a thread with a pointed stylus and seeing which way it advances. If both are RH, and an Italian cup seeps to fit, the next step would be to properly clean or retap the thread.

Very true. However, it is very unlikely that anyone except a very experienced bike mechanic or a well equipped repair shop would have the right cutters, so you would be putting the frame into experienced hands

Sadly, this isn't a given. Many shops have the tools left over from when they were more commonly used. But the skill set disappeared with staff turnover in the intervening years, so there's an excellent chance that the mechanics there only think they know what they're doing. (which wouldn't be excellent a all).