I'd say, if you can reasonably afford new bike, go for it. And if you might end up not going for it, don't let the reason be to leave more money to your children or whoever else. Its better for children to fend for themselves anyway. I only write this because I've seen too many people with that motivation who forwent (not sure I just made the word up, it is meant to be past time for 'forgo'
, probably I should use 'denied themselves') buying something they wanted for themselves.
Looked it up and my hunch was right, past tense is indeed 'forwent'.