ianstock

I am trying to change the stem on my 2000 Pinarello Prince, and can't get the tubular insert and top-cap assembly back together.

Inside the steerer tube there is a plug, into which I have to thread the upper plug and top cap assembly. The lower plug flips around and getting the threaded bolt to hit the lower plug seems impossible.

Is there a secret to doing this or does it just require the patience of Jobe?

Ian

Bianchigirll 

I am not familiar with this setup, and maybe some others are not as well. can you post a few pics?

it sounds to me like the part in the steerer that is 'flipping over' perhaps should have come out with the stem cap. this does not ahave a starnut in the steerer but uses a comperssion type plug right?

HillRider

I assume this is an expander plug and what is "flipping over" is the lower part. There should be a 5 mm hex recess in the top of the loose part. Put a suitable allen key in it and tighten it up snugly. Be sure it is set the correct distance below the top of the steerer so the topcap can reach it. That should lock it in place and allow the topcap to thread on.

fietsbob

If its a steel steerer, then a star-fangled nut was probably used. aluminum maybe , carbon there will be a expander to tighten first, in the tube, then the center bolt applies the bearing pre-load, thru the whole stack , loosened stem to steerer bolts and spacers..

Integrated headsets are a whole new challenge ... I added a 'Locking spacer' ,QBP, immediately above the top race.
essentially a 9/8" seat binder clamp that's squared off, on top and bottom , and not very thick ,
{ got room, a thicker one made to go on the top of seat tubes will do}

holds the stack of loose parts in place while you fuss with the rest of the collection above it.

ianstock

Here is a photo of the upper pieces. It seems as though the this assembly is not long enough to hit the lower expansion plug, even though it is teh same hardware that came out.

ianstock

One more thing. The lower plug falls into the steerer so if I don't try to thread into it with the frame upside down, I'll never get the bolt to even reach it.

Seems like madness to me.

fietsbob

If the steerer tube is long enough , I like BBB's BHP 21 its a quill going inside the steerer, (probably not for CF steerers, mine is steel )
and the quill expander bolt is internally threaded, so after tightening the quill, the cap bolt threads into the top end of the expander bolt.

includes a number of keyed shim spacers to add height to a too short steerer, or you can put its whole length inside the steerer, except for really short frames..

ianstock

Steerer is carbon.

HillRider

You've got pieces missing and they maybe inside the steerer. The silver part to the left of the photo should have a pair or three parts that wrap around the cylindrical body and act as wedges to tighten the assembly in place by using the bolt. Once that assembly is tightened in the steerer, the topcap has female threads that thread down over the mail threads on the left-side part.

DaveSSS 

The picture shows improper assembly. The part inside the steering tube should be threaded. Get a bolt long enough to reach it, screw it in a couple of turns and pull it out. You could also take a length of coat hanger wire with a small hook bent at the end, to insert into the hole, catch the lower edge and pull it out.

Normally, the conical part in your picture goes under the part that's in the steerer. Tightening the center bolt expands the plug, so it stay where it's placed and allows the top cap to apply pressure to the top of the steerer.

ianstock

Thank you. That makes it a lot easier.

Those Italians aren't as crazy as I thought.

Ian

coppikat

darn right about those Italian's, they make good bikes and components. I'm one

grumpus

A bike or a component? Oh, it doesn't matter, everyone else left 13 years ago.