if you want to convince yourself, push the front wheel against a wall head on while holding the rear wheel down.
if you can get the front wheel to flex 1/2 the distance to the DT, i'd guess you're in danger. (regardless of the result, i'd still think it's too close.)
the risk is that an unseen bump will force the wheel backwards into the DT. the second it touches it, it's game over. the bike will slow due to resistance on the front wheel, and the wheel is forced further into the DT, increasing the resistance. this continues until you go end over end and possibly damage the frame.
what unseen bump you say? the one you hit 3 months ago and were surprised you didn't get a flat.
the worst part about the error is that it only occurs when the forces are great enough... such as when you're moving quickly.
i spell it out in detail so you'll actually give it some thought.
deleted
@bright
if you want to convince yourself, push the front wheel against a wall head on while holding the rear wheel down.
if you can get the front wheel to flex 1/2 the distance to the DT, i'd guess you're in danger. (regardless of the result, i'd still think it's too close.)
the risk is that an unseen bump will force the wheel backwards into the DT. the second it touches it, it's game over. the bike will slow due to resistance on the front wheel, and the wheel is forced further into the DT, increasing the resistance. this continues until you go end over end and possibly damage the frame.
what unseen bump you say? the one you hit 3 months ago and were surprised you didn't get a flat.
the worst part about the error is that it only occurs when the forces are great enough... such as when you're moving quickly.
i spell it out in detail so you'll actually give it some thought.