I’m a keen recreational cyclist (hardcore bimbler) riding on and off road, but have no technical skills to speak off. Consequently the finer (or indeed any) points of frame geometry have passed me by; I’ve had no issues buying frames in roughly the right size and tweaking saddle and bar positions until things feel ‘just right’.

However, back in November, for my 50th birthday, I treated myself to a Singular Swift frame which has an EBB. I’m constrained to placing the BB in the upper half of its range due to the fact that I need chainstay clearance for a front mech. (I’m running a triple). Currently my BB sits at roughly the 2 O’clock position (viewed from the drive side) which works well enough.  I could wind it back to 11 O’clock though, which I’m guessing would place it around 3cm further back, effectively shortening the chainstays.

I’d need to adjust the saddle (and possibly cockpit) accordingly, but would I notice a difference and would there be any advantages/disadvantages to doing so (bearing in mind my non-technical poottling style of riding)?

Tapping the BB back is straightforward so I could just try it and see, but thought that I’d ask too.

The thing I’d be most worried about would be your knee-position relative to your pedals, unless you are also going to slide your saddle back to match as you suggest. Of course, that then might mean a longer reach and therefore other discomforts.

Given that discomfort is the thing most likely to affect your enjoyment and performance, I’d leave it where it is if it’s not causing you any grief.

Effectively steepening the st should make it easier to get out of the saddle and mean your hips are less bent .

Try it and see

what’s the offset from centre of one of these things ?  I’m betting maybe half a cm, def less than 1cm

You’re going from 2 o’clock (maybe half of that offset ahead of BB centre) to 11 o’clock (well under half that offset behind BB centre). I’m going for less than a cm difference further back (and virtually no different vertically)

You won’t even notice is my guess

Thanks for the thoughts. It doesn’t sound as if it’ll make much of a difference (or any) and I may have overestimated the amount the BB position will change.

I make give it a try sometime and see as it’ll be fairly easy to do.

The easiest thing to do is try it, which, as you’re not running it singlespeed, you can do without any chain tension issues. It’ll take all of one minute.  No need to tap the insert back, btw – just use a 6mm allen key in the hole in the insert and rotate it back.