Permanent seat lock?
 

I've been trying to find a way to secure my seat to the frame in a semi-permanent manner. Have any of you done this and how?

By the way, a cable with padlock won't do. I don't want anything bulky.

I'm thinking maybe a renovation center cable with some tightening hardware might do.

Weld it?

Why semi-permanent? Theft protection? Perhaps a Pitlock?

Here's mine: get a carbon frame and an aluminum seat post. Let a little moisture get in there. Wait a year or so. Bingo: it's permanent.

Use an bolt with a tamperproof/security specialty head or allen key.
It weighs the same as your current set-up and is very theft resistant.
Sure, it is possible to steal your seat, but chances are they would move to the next bike instead.
If you need to adjust the seat hieght, replace the seat, etc... No problem!
Just don't lose the adapter bit ;)

Well there's permanently attaching the seatpost to the frame and then there's permanently attaching the seat to the seatpost. Best I can think of is replacing QR seatpost clamp w/ bolt, and then somehow mung all attachment points. Krazy-glue a bb into allen head on seatpost clamp and saddle mount, that kind of thing.

Plosive, thanks for the link. I'm planning on customizing my old hybrid and was wondering out to secure the seat (not just the seat post, like the Pitlock does). :beer:

Where do I get these bolts? When i looked at the website, the minimum order qty was 2500 ea. for $1500.
That's maybe 10 times the price of OP's 'old hybrid'.
Duppie

You could just use allen head bolts (from any hardware store) and fill the head with epoxy or something. You can dig it out if you have to but it'd take a while. Watch out that the sides aren't flat of they will be able to defeat it with vice-grips.

If you don't mind taking a torch to it, solder would be a good filler. That's if you don't mind scorching a little paint.

Keep in mind that nothing is secure to a guy with a battery powered grinder. That's not unheard of on the streets.

2 options (sorry for no pictures)

buy a seat security cable (the thin short ones). Loop it around the seat tube, pass it through the saddle rails, pass the seat post through the free end, fix the saddle to the seat post, insert the seat post into the seat tube, coil it around the seat post by rotating the whole seat post until all slack is taken up, set seat post to desired height, tighten all bolts, using silicone bathroom sealant fill all bolt heads.

adjust the seat post and saddle to the desired height, loop a short length of bicycle chain through the saddle rails and under the top tube (cross bar), using a chain tool join the bicycle chain

Here's a thought; there may be some small car lug nuts that are of a suitable size to use in this situation. If so, you can buy locking nuts for these with a keyed top. You need to find something like a carriage bolt (round top, nothing to grab with vice grips) for the bolt.

Pit Lock makes a proprietary nut and sleeve system for securing your seatpost.
Peter White carries them.

My bike has a seatpost clamp with a hex nut (Surly Constrictor). This is probably enough, but I'm not 100% sure it's enough. Of course I didn't want something 100% permanent. But I want something that cannot be removed without a few tools. I'll go and get stuff at the renovation center, that's gonna do fine.

You could get an OnGuard seat leash. Although anyone with bolt cutters will have that out of the way in no time at all.

use an old bike chain wrapped in an old innertube and chain the rails to the seat stay

u'd need a chain tool or a lot of desire to get that seat. what kind of seat is it anyway?

+1

That's what jyossarian recommends, and he's basically the head of HHCMF

I use a Pinhead locking skewer for my seatpost

But it still leaves my Brooks vulnerable through the allen bolt on the microadjust portion of the post. Been looking to replace that with a security bolt of some sort

+1

Plus you can buy a set for your wheels too, and use the same key to unlock the entire set-up.

If filled mine with pl premium construction adhesive, I know it can be picked out of their if need be, but it will slow down the thief. I had to do it once, and it took about 5 minutes with a small screwdriver to pick it out.

+2. This is the standard New York City method of securing the seat to the bike. There's no such thing as theft-proofing anything here, but this is as close as you're going to get. Wrapping the chain in electrical tape rather than an inner tube makes it a bit less bulky.

security screws?
 

I've just ordered a set of Pitlocks but I too am worried about the saddle being removed from the seatpost.

Has anyone actually bought security bolts like the Bryce Fasteners linked above? This seems like a potentially good solution, but I too am unsure where to obtain just a handful of them. That site disparages other kinds of "tamper-resistant" bolts, but perhaps these are easier to find and would seem to offer a good measure of security against casual thieves. such as: http://www.tamperproof.com/

What I really want is a seat post with a locking clamp that can't be opened (to remove the saddle) without a key. Does this exist?

Lots of people have the bike chain inside inner tube solution here in the Bay Area... but is a bike chain really harder to cut through than a cable? And can't someone with a chain tool just unlock the chain? That probably would take under a minute for a thief with some practice (given that it's such a common method around here).

+1.

I have the set that includes skewers, threadless fork cap and seatpost bolt. For my second bike I have a second set on order that's keyed the same as the first set.

After a stop at the hardware store for a $1.19 clevis pin, I can keep the Pit "key" on my keyring.

Security Screws/Chain Wrap/Tamper Proofing Existing Bolt
 

I had my 20 year old books saddle stolen last week so I've been doing a lot of thinking and research on this question. I want to replace it with another expensive brooks saddle (you know -- just because). I'm buying Pitlocks. That only works however for wheels and the post to frame connection. A keyed security bolt would be an elegant solution for the saddle connection. The typical bolt is an M8 1.25 40mm. Without buying expensive bulk, this bolt appears impossible to find. With more research, I might be able to find it off a British site.

End of day, I think I'm going to fill the socket head with solder and put a bike chain with electrical tape around it. Solder removal tools are cheap. At least that's the plan. I'll tell you how it turns out.

Just Krazy Glue the bolts in place. Krazy glue comes off easily with acetone so you can remove it when you eventually need to. Unless you need to change your seat height or angle frequently this will work. The would be thief isn't going to know what he is up against and will quickly move on to someone else's bike. All the other methods can be defeated with a cutter but bike part thieves aren't in the habit of carrying around acetone. I would use this strategy myself except my seat post doubles as a pump.:D