Last ride 76 

Not a record I ever imagined I would, or ever wanted to, break.
I was ready to find a frozen seat post, since it was sunk so far down into the tube ... What the heck were they thinking? This is coming from a guy that swapped out chromed steel Campy brake nuts for aluminum, and drilled out everything he could find, including an alloy kickstand, but this, this is just goofy. The 1st one, on top of the stand, was part of a '75 Gios Torino- one owner, never raced, IIRC, and now this? Doesn't this say "My frame's way too big?" Anyone need a good deal on (2) too short seatposts?
Wait a minute, I just realized these both originally came from Texas, right about the same time... Mid-seventies. Was this a Texas "thing" BITD?


Wait for it...


Exactly 3 1/2 ( just under 9cm) inches of post. The cut is so shiny, it looks like it was done yesterday...

Bianchigirll 

Is that a Teledyne? Your going to post pics of a teledyne and not drop the name?

I don't think it is as much a "texas thing" as a weight weenie thing. Guys would cut the post to save weight. Some drilled them. I know one guy who broke a post or two by somehow machining down the tube from the inside!

T-Mar

Cutting a seat post was a "weight weenie" move. Once you established your proper seat height, you would mark it where it entered the frame using tape. Then you removed the post and cut it 2" below the tape, removing the unrequired portion of the post and its related weight. This is consistent with a person replacing steel nuts with aluminum.

Drillium Dude 

Yeah, it's definitely a thing. This guy took it a step further:



DD

ThermionicScott 

I've done it to a couple of my seat posts, although leaving a more conservative 3" to extend into the frame. I figure my legs aren't getting any longer, so why not?

Drillium Dude 

I guess that would be my question: how do you know how much is safe to cut off? Although I've drilled a few posts, I've never cut one.

DD

SurferRosa

I've also cut down a seatpost, but it was one of those modern ones that's like 3 ft long. A pipe cutter made simple work of it.

OldsCOOL

I’ve cut a few down but went the more conservative 3”. Weight weenie stuff.

ThermionicScott 

I did a lot of reading here on BF before doing the deed. Erstwhile member FBinNY suggested two rules of thumb for minimum seat post insertion: 1) two and a half diameters of the seat post inside the frame, or 2) one diameter's worth below the bottom of the top tube. I feel like the latter rule becomes more critical now that we're seeing frames with seat tubes that extend way above the top tube.

So in my case, with a 26.6mm post, that worked out to 66.5mm for the first rule, 52mm for the second rule. I stopped at about 75mm, figuring that my returns would diminish beyond that point anyway.

dddd

Being long of leg in proportion, I usually go ahead and cut off any non-valuable post about 3" below insertion point.

This way I can still alter the height for possible use of a shorter saddle later on and still with plenty of overlap.

I tend to run my saddle forward and weigh under 150#, so I could probably get away with a drillium post.

Even on the modern bikes I've built for others, I sometimes find there is easily an extra several inches of carbon post to be cut off for weight savings.

Drillium Dude 

Thanks for the detailed response. I might look into this, see where my stuff is at currently. Then perhaps I'll have a project for this winter

DD

Last ride 76 

My original road seatpost, traces of Masi Orange .


My original track post, deeper cuts were made because the post slipped in the vice, and to cover the oops.... Once I cut it too deep, no matter how many more times I cut it...
Folks, I GET the weight weenie thing... but riding a big frame and a short post, Umm, better check that scale again... I out weenied most folks, DIY in high school, taking jewelry smithing classes. I also rode a SC Medaille D'Or 32 h radial wheel, and built, but never raced a 32h high-e small flange folded sheet rim. 3 1/2" post - nope.

Drillium Dude 

French fit with a hidden variation

DD

T-Mar

Our rule of thumb for seat post insertion was a minimum of 2". Once manufacturers started marking the minimum insertion point, you could always measure that distance and use it as your guide.guide. There were some who adhered to the belief that where was sufficient insertion provided that the end of the post was not visible in the cinch slot.

Once dual suspension ATBs with Y-frames started appearing, I started running into seat post length issues on children's bicycles. Parents routinely insisted on buying too large a frame that the kids would "grow into". As much as I tried to dissuade this, most parents would not relent. This would require the saddles to be slammed to or near the top of the abbreviated seat tube and the long ATB posts would contact the top of the swingarms, locking out the rear suspension. Parents would then request we cut the bottom of the post. However, that compromised or eliminated the minimum insertion markings and could result in a liability lawsuit. Some parents understood but I lost quite a few sales for refusing to cut posts.

crank_addict

Before you suggest, no- I'm not totally into the vintage weight weenie thing, but admit now have a good start by going smaller frame size. Here's some examples that I'm enjoying. Zero issues running seatpost at their limit marks.

Campy two bolt maxed out on Reynolds 531 frame.
Dura Ace on vintage 100% pure titanium and J.P.R. on vintage Vitus 980 steel.

xiaoman1 

DD,
By the guy did you mean you?
Ben

crank_addict

Any close up or info on the pedals (Bob Reedy track)??

Kuromori

It still is. In fact, sometimes I have to cut long seatposts to clear seat tube bottle bosses.

Drillium Dude 

Nope, I've never done anything quite that extreme.

DD

seedsbelize 

My most recent purchase had a cut seatpost. First I'd seen it. I was picking it up and setting off on tour with it. Thankfully there was enough of it left.

Cyclist753

..

JohnDThompson 

Those sawed-off posts are good for salvaging the often-missing rail clamp pieces, at least.

3speedslow

Since I move parts around from project to project, I leave all post like I get them.

easyupbug 

I hate finding a cut posts, unless it a modern substitute that is as said above 3' long. After all butchering a nice Sugino fluted post to save a fraction of a watt on a C&V is just crazy to me.

ThermionicScott 

Cut posts should be disclosed to the buyer! I love cutting posts, but I want to make that clear.