i bought a steel frame and had it built up into a pretty sweet bike last year. unfortunately, i was not savvy enough to get it treated with some sort of rust/corrosion prevention solution prior to the build up. i live a dry climate, so it's not bathed in humidity, but it is a mtn bike and splashes across a creek from time to time. and i have noticed a thin layer of rust in the seat tube.

does it make sense to go ahead and have it treated at this point, or have i missed the window?

how much disassembly would be required? i'm picturing simply pouring the solution down the seat tube and just turning the bike this way and that to slosh it around the frame, maybe with the wheels off. that simple?

thanks.

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...to do it right, you'll have to pull the stem, seatpost, and bottom bracket. NOt a ton of work, but yes, it makes more sense to do it when the bike is stripped . I use this stuff, and spray it in with a red plastic nozzle straw, so I can usually get the fork legs and the seat stays through the tiny hole left for expansion during brazing. They sell it at Home Depot here in the paint aisle.

Your frame should be fine at this point but, if you go through water frequently, rustproofing the interior is a good idea.

Done right, you have to strip the frame completely with the possible exception of the headset cups. Use either Weigel's Framesaver (from most bike shops) or Amsoil HDMP (from most NAPA automotive dealers) and spray it into every tube including the chain and seat stays and fork blades Use the vent holes to get into the small tubes. Spray the coating lavishly into the tubes and rotate the frame frequently to distribute the liquid. Let it dry for a day or two and repeat. Do it outside and put plenty of newspaper under the frame to catch any drippings.

If you will be doing a lot of stream fording you might consider drilling a small weep hole in the low point of your BB shell. Water IS going to get in and you might want to give it an easy way out. Of course you will want to paint the raw edges of the hole to keep it from rusting. If you are going to apply frame saver you would want to, as a minimum, remove the BB and when it is out would be a good time to do this. Stripping the frame as HillRider suggests would be the ideal situation, but even a non-ideal application would be better than leaving it bare.

What frame? Many steel frames, like Surly, are factory treated.

Edit: I take that back. Surly are definitely not rust proofed. Some other manufacturers do, such as Seven.

Really? I didn't know that. Maybe I wasted my time Amsoil HDMP treating my surly Pacer frame. It should last forever now.

If the build will be powder coated, the rust protection should go in after the frame is baked.

I think it's All City that ED coats it's frames.

Edited above: I was mistaken. Some Surly frames have an ED coating which acts to prevent rust, but not all.