Bicycle Mechanics - Upgrading my frame??? what will fit?

I have an old marlboro edition Fuji collapsable mountain bike and im not a huge fan of how it rides. Can i just buy a used frame and swap all of the components over? What do i need to look for when swapping frames? Also i want to add a suspension fork if i can find a cheap one. Will it be a simple swap?
Right now i use it as a commuter bike for school but i really enjoy riding and i want something i can take off road a lot.

Most of what you have will fit if you find the right frame. If you want suspension forks, it will probably be cheaper and easier to sell your bike and buy another that has what you want.

If you're getting a frame and fork MTB setup then likely it'll be threadless 1 1/8 these days. If your old bike has a threaded or 1 inch setup then you'll also need a new headset. But other than that it SHOULD all go over just fine.

What about the shifters, how hard is it to swap those out? I had ones that clicked once to shift but the current bike you have to slide a lever to line it up with the numbers and its quite a pain compared to my old setup. I guess ill start looking for a frame online once i get some measurements on my current frame

What about the shifters, how hard is it to swap those out? Mechanically it's quite simple, although it helps if you've had some experience replacing cables before. Getting the grips off to get to the shifters may well be the hardest part.
But the shifters have to be compatible with the rear derailer/cassette, and this requires some knowledge.


.. I had ones that clicked once to shift Sounds like you had a version of trigger shifters before.


.. but the current bike you have to slide a lever to line it up with the numbers
This description is a bit more vague. Will the lever click into place, or will it just slide smoothly through the whole range? If it's just one smooth motion, then it's a friction shifter and those are actually preferred by some people. Reason being they can be used with just about any derailer/cassette with a bit of skill from the rider. If the lever have noticeable stops by each gear, then it's still an indexed shifter and needs to be matched to the derailer/cassette.

Not sure if different mtn bike tube diameters exist, but with my road bike the seat tube diameter was different on the new frame, requiring a new seatpost and front derailleur.

Im looking on ebay and I see a few suntour xcr forks new for under $100 (some closer to $30). Would that be a decent upgrade to a solid fork or would i be wasting my time? Im not going to be riding off road nearly as much as i will be commuting but i do want something that can absorb a little impact for when im riding. Basically looking to get my cheap bike to more of an entry level free ride bike and i was thinking an aluminum frame and an ok fork would be a nice step up.

Im looking on ebay and I see a few suntour xcr forks new for under $100 (some closer to $30). Would that be a decent upgrade to a solid fork or would i be wasting my time?

If your frame was designed for a rigid fork, slapping on a sus fork will change the geometry, making the handling sluggish. The slacker angle will also add stress to the head tube/ down tube joint. There are also two possible diameters to keep track of. If you're currently using canti brakes you will most likely find it hard to use a modern fork. In all it's quite a lot more than simply pulling the old one out and jamming the new one in there.


Im not going to be riding off road nearly as much ...Basically looking to get my cheap bike to more of an entry level free ride bike
Suntour forks are a bit of an unknown. They're so suspiscously cheap that there aren't many MTB-ers using them.


.. Im not going to be riding off road nearly as much as i will be commuting but i do want something that can absorb a little impact for when im riding. .

I wouldn't consider sticking a sus fork w/o lockout on a bike that will see most road use. And I'm really fond of rather light weight forks. Then again, I'm into XC.
But for a mainly commuter I'd stick with a rigid fork. It'll be more efficient on the road, and not much of a drawback on easier singletracks either.


..I see a few suntour xcr forks new for under $100 ..would i be wasting my time?... Basically looking to get my cheap bike to more of an entry level free ride bike and i was thinking an aluminum frame and an ok fork would be a nice step up.

This is beginning to sound like a "throwing good money after bad" scheme. A free ride bike that doubles as a commuter is a poor compromise. And freeride can still stress a bike enough so that you really don't want to use anything but stuff that's strong enough to take it. Better then to keep one bike as a more dedicated commuter and save up for a purpose built F/R bike.

Had a quick look at Suntour, and I only saw 100 mm travel, which is kinda short for Freeride.

And while it's likely to be an aluminium frame either way, material doesn't say it all. There are poor frames as well as nice frames in every material.