I am a frame builder AMA

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Lolo in reply to @paulbiche

2) Thought about lowering the BB to 270mm high. I don't like pedal strikes, and have the habits of fixed gear pedaling almost constantly, but as this one will be geared and I read that low BB is preferable for bike stability, I thought it could be good to lower it. But I don't want to have it too low either ; so what are the advised BB height for this use? is 270mm coherent? is it really necessary to lower the BB?

) Thought about lowering the BB to 270mm high. I don't like pedal strikes, and have the habits of fixed gear pedaling almost constantly, but as this one will be geared and I read that low BB is preferable for bike stability, I thought it could be good to lower it. But I don't want to have it too low either ; so what are the advised BB height for this use? is 270mm coherent? is it really necessary to lower the BB?

I've done a bit of reading on the subject. A low BB certainly gives a more planted feel and interestingly it seems that a lot of custom bikes have a bigger BB drop than OTP. Some (most?) of it might be more psychological than pure physics, but for example a modern US geo CX bike feels more stable than an old school euro one.
270mm is a bit high for a rando bike IMHO, with no benefits, but if that's what you prefer go for it. Or, as always, let the builder do its job.

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Hulsroy in reply to @Lolo

270mm is not high.

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Lolo in reply to @Hulsroy

If this is correct Merckx's bike at that time was on 265. If that's good enough for cornering when racing, with clearance required for wide pedal and cages, does a rando bike really need a higher BB (I understand it'll be just fine)?

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