Threaded Headset Help

[PWong87]

I'm thinking of replacing the headset on my Merckx and trying to figure out the stack height I'll need on the new headset.

I believe I have a Stronglight A9 (see attached pic) based on faded "Stronglight France" written on the locknut. Only problem is I'm measuring about 40mm of stack height but I think the A9 has a stack height of 38mm.

Anyone know why this might be? Did the previous owner swap out the washer for a spacer? I was hoping to get a CK Gripnut or Cane Creek 110 that only have stack heights of 38mm.

Btw I calculated my stack height by taking the locknut off I measured from the bottom of the crown race seat to the top of the steerer tube then subtracted the headtube length. I guess I could remove the whole headset but that's more involved.

[peanutgallery]

Metric length of the headtube plus 41mm, this is that campy standard and was usually the tallest. 40mm is close and that is what the previous owner was going for. Use 1"headset spacers as needed. Sounds like your all good

Get this guy a Sutherlands Manual

[PWong87]

It seems my initial googlefu was inadequate. Further searching suggests the A9 has a stack height of 40.2mm so everything makes sense now.

Guess I'll have to go with a 2nut rather than GripNut.

[oliver1850]

My 1994 catalog lists the A9 and Delta as having a 42 mm stack height. I measure the Delta on my '87 Cannondale (pretty sure it's original) at not much over 36 mm. Looks to have a normal 2-3 mm washer under the top nut.

The Stronglight X14 is listed with a 39 mm stack height. The X15 at 40.3 but only shown in 1 1/8".

Best way to sort your issue out is to pull the fork and measure the steerer tube and head tube of the frame.

[Peter P.]

Originally Posted by peanutgallery

Get this guy a Sutherlands Manual

Stronglight A9: 39.8mm. From the 6th Edition of the Sutherland's Manual.

[oldpotatoe]

Originally Posted by PWong87

I'm thinking of replacing the headset on my Merckx and trying to figure out the stack height I'll need on the new headset.

I believe I have a Stronglight A9 (see attached pic) based on faded "Stronglight France" written on the locknut. Only problem is I'm measuring about 40mm of stack height but I think the A9 has a stack height of 38mm.

Anyone know why this might be? Did the previous owner swap out the washer for a spacer? I was hoping to get a CK Gripnut or Cane Creek 110 that only have stack heights of 38mm.

Btw I calculated my stack height by taking the locknut off I measured from the bottom of the crown race seat to the top of the steerer tube then subtracted the headtube length. I guess I could remove the whole headset but that's more involved.

That's it...Measure the headtube and then the length of the fork steerer...fork crown race seat to end of steerer and that's the minimum stack height headset you can use.

[PWong87]

Originally Posted by oliver1850

My 1994 catalog lists the A9 and Delta as having a 42 mm stack height. I measure the Delta on my '87 Cannondale (pretty sure it's original) at not much over 36 mm. Looks to have a normal 2-3 mm washer under the top nut.

The Stronglight X14 is listed with a 39 mm stack height. The X15 at 40.3 but only shown in 1 1/8".

Best way to sort your issue out is to pull the fork and measure the steerer tube and head tube of the frame.

Ya looks like this is what I'll have to do.