I had replied, and apparently it didn't make it in before the boards went down for maintenance.
I think asking for a donation would have been OK, but presuming that you will donate is not. My usual answer is that I've donated quite a bit to my local charities already, and that I don't have any more in my budget. There are lots of good charities out there, and we all should be able to choose the ones we want to donate to without feeling pressured. I've hesitated to do fundraising rides because i don't like to make people uncomfortable though
Not the best result, clearly, for me or the charity.
So...I would say don't donate unless you really want to. You certainly shouldn't feel obligated.
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