Originally Posted by
daihard
To be clear, my wife is complaining about the ride on the uphill streets, not off-road. She hopes (and I do too) that thinner, road tyres will help her ride up those hills with less effort.
Slicks will help but the Marlin is still a boat anchor. It was a entry level mountain bike with a whole bunch of iron parts. The fork alone is going to weigh in around 3 lbs...and is unnecessary for on road riding. Unfortunately you have a problem here that isn't easy to fix. But for a lighter bike, your wife would probably enjoy riding a bicycle more. To get a lighter bike, you'll need to spend cash to either retrofit the Marlin or buy a new bike. Retrofitting the Marlin and attempting to lose several pounds is going to be expensive. At the very least it will likely cost what the Marlin did new. Now you have around $800 invested in a $400 bike and it still wouldn't be all that light.
I'd suggest starting with a new bike that is sized to fit your wife. And don't skimp on it. Spend enough to get something that is light enough for her to power up hills. Try to get something in the low 20 lb in terms of weight. That's not going to be cheap. To justify the cost, think of the weight differential between you and your Quick and the weight differential between your wife and her Marlin. You have a bike that is a smaller fraction of your mass than she does
and, not to take anything away from women, she has less muscle mass to push that bike around with.