dents in top tube, are they critical?

Browsing the web and looking at NJS frames available for sale, it appears many have dents in the top tube, most likely caused by handlebars spinning and bashing them in tumbles on the track I suppose.... or just some careless bike carrying....

Just how critical are these in terms of the strength of the frame, is it compromised much/at all ?

Ta

probably not something you can tell without actually seeing the frame. Dents can look very different in photos to real life. if in doubt don't buy - njs is by no means a mark of quality, more of a standardisation. if it's a decent strong frame you are after you would be much better off buying something from a british frame builder. However, if you are a magpie, go for it.

Ask Build, Slam, Object, MA3K or Jonny about dents and riding.

Nope, not a magpie, I wont be swayed just cos its shiny with an njs stamp on it.
It is dubious seeing all the dents on them, they must remove them from racing use for a reason after any crash, hence they are strong enough, but the potential damage behind any crash dent would be a worry.

drumon, you must understand that your question is totally dependent on the dent itself, so nobody can really give you an answer.

If it's a big dent, then yes it will be compromised, but its steel so also can be replaced, if it's a small dent, no probably not.

One thing to bear in mind is that a lot of NJS bikes use thoroughly ridiculously thin tubes, and if it has a dent in it (even a small one), it would've been deemed unsuitable for riding on the track. Therefore, it's not a great thing to ride one on the road. In my opinion.

understand you, thats what I was wondering considering that they are no longer raced after a crash. thanks for the tips.

Ask Build, Slam, Object, MA3K or Jonny about dents and riding.
You can't really put Ma3k and myself on that list. Steamrollers are tanks disguised as bikes.