I may be able to borrow a lighter bike (a hybrid) of a friend who is relatively the same height. I think it's a pretty new bike (unlike say mine which is from the 70s) so it will have more gears than 5 or 6, but my bf said I could get the principle down practicing on my bike and will likely be fine race day with the better bike. Also he says he's worried that the chain might snap on my bike (he also said the reason he told me not to do the sprint, or one of them, is that I've never changed a tire without him watching and directing me, so that if I got a flat, I wouldn't know what to do - I know, I need to learn!).

Is it a terrible idea? I'm thinking actually that maybe it's not a bad idea to borrow the better bike if I'm able. Thoughts?

(oh and this week has been TERRIBLE for training, but at least this weekend fastpacking we're doing a 45k day and then a 34k day)