Super tight headset bearings?

Hi everyone I need some help.

I recently bought a used frame that has an integrated headset. I’ve bought new bearings for the top and bottom but the bottom is so tight I’m struggling to get it in. I can just about wedge it in with a lot of force but then it’s impossible to get out. Is this normal for some frames?

The top bearing drops in no problem and is easy to remove.

Thank you

How’s the old one, and how do they compare in size side by side?

For reference, on my old YT, they used to more or less fall out when untensioned. It was only the compression of the headset and the taper of the bearings that used to keep them in place.

It came without a headset.

Is the bearing seat clean i.e no corrosion

What frame

What size bearings do you have 

Yes it all appears to be clean and normal.

It’s a Santa Cruz Chameleon v7 with IS IS 52/40 lower bearing. I’ve tried Hope and Cane Creek and they are super tight. I can’t get it in with a rubber mallet but it’s a pig to get out again. I’m guessing that’s not normal?

Any pics?

Tapered – Integrated Headset. 1-1/8″ Upper bearing and 1.5″ Lower bearing. S.H.I.S. IS 41/28.6 IS 52/40

It’s a bit of a stab in the dark but I don’t suppose someone’s forced in an internal cup for a semi-integrated headset?

Failing that it might be a tolerance issue. The Park website has tools and instructions for reaming headtubes for integrated headsets so perhaps this needs doing.

Thank you everyone, much appreciated.

Would a quick sanding out the inside face  be inappropriate and wrong?

Not all headset bearings are made equal. The lower headtube should be circular and 52.1mm internal to take a 52mm bearing

FSA make a 51.8mm/40mm bearing

I’ve had it with a semi integrated (zero stack) headset, it took quite some force to seat the top bearing. It is still running fine around 8 years later so didn’t cause issues.

When you got it in how did the bearings feel? I would have thought they wouldn’t move easily if you had really needed to force it.

Try freezing it before fitting too.

I’ve had this with ZS lower cups being too tight after pressing in, I went with 51.9mm bearing from kinetic bearings instead of the supplied 52mm. Forcing a bearing in is a bad idea, no point if comes out in pieces leaving the outer race jammed inside, that’s what happened in my case, I had to prise it out bending it in the process, the 51.9 slotted in perfectly, just make sure you get the correct degrees and height of the bearing.

Sounds like your hole needs reaming, go to a bike shop.

Thank you everyone.

The bearing does rotate once in but it’s a pig to get it in and out. I thought they were meant to drop in like the top does.

Maybe I’ll try a local bike shop to see if they can help.

I was worried I’d been sold a damaged frame. The seller assured me it was never a problem for him.

Put the bearing in the freezer and keep the frame in a warm room overnight – it’ll probably drop in

If you’ve got some verniers, I’d try measuring the ID at a few points, just to double check it hasn’t ovalised.

Great idea

dovebiker beat me to it.

Bearing in the freezer (in a plastic bag). Even an hour in there will make a huge difference 

You really don’t want to be forcing anything into an ally headtube (if that’s what it is) by freezing, hammering or anything else

That area is possibly one of the most stressed in a bike