Hi all, I'm new to the Motor Bike world and I'm just starting my first build. I found a fairly nice condition Columbia Rambler for $60 at my local flea market and would like to make a nice vintage cruiser with the Chinese engine kit I just purchased. My first question is: With the curved downtube of the Columbia frame the engine doesn't cradle into the lower section because the gap is too wide so I guess I need to somehow extend my mounts to fit the frame. What is the best way to do this? I'm thinking I should use the forward mount as is and extend the rear mount? Are there any threads that have dealt with this topic? Next question is: Can I replace the existing dry rotted 26X1.75 tires with new 26X2.125 tires without changing rims? I understand there may be clearance issues with the fender or frame but my concern is whether I need wider rims too. I'm sure I'll have a lot more questions as I get into it. Sorry if these are easily answered or previously covered topics but I've been looking around on the forum and haven't found the right answers. Here's a picture of my Rambler. What do you think?