Triaxtremec

I currently have an old Diamondback mountain bike with one heavy as hell frame. Thinking of trying one of these carbon frames off ebay and swapping all the components over as well as try to fine a cheap front shock. Is this something that I can do without having to dump to much $$ into or should I just keep the bike the way it is. I was hoping the new frame would accept my older components just be a lot lighter.

https://cgi.ebay.com/Carbon-Mountain-...item3a5f12a7d1

dabac

Bikes usually aren't heavy due to one single component, but b/c the majority of the parts are on the heavy side. Swapping a frame for the explicit purpose of getting a lighter bike can be quite disappointing in terms of payoff and investment. You might be able to shed one pound through all that hassle. It's also rare to be able to pull off a frame swap w/o having to buy some new bits (seat post, front derailer etc).
And if you want a new fork too, then it'd make far more sense to go for another bike entirely instead.

abdon 

The first thing you need is a second bike, because this one will be down for a LOT longer than you think. I'm doing a frame swap and it is taking well over a month because there is always something I don't have and have to order.

The latest setback was quite something; I bought this particular frame because it came with a set of Tiagra brake/shifter levers. On the first commuting trip, the front shifter lever locked up and now needs to be replaced

The good news is that it provides you the perfect excuse to sneak in a bunch of upgrades that you would not otherwise have the heart to spend the money on (now I'm waiting for a set of bar end shifters)

CACycling

For the most part, the DBs with the heavy frames also had cheap components. And cheap suspension forks tend to be heavy and inefficient. You'd be better served to save up your money and either buy or build a new bike. Most likely will be cheaper in the long run.

fietsbob

Buy a complete bike, the factory buys parts by the thousands ,
and gets the best price.
buying parts as an each is lots more expensive,
but the parts pick is Yours.


Why buy a CF frame sight un seen from Hong Kong?,
just get a bike from the local Bike shop.
Metal is more durable ..
and durability is what you need for off road racing.

HillRider

Simple answer: It won't save nearly as much weight as you think and it will cost a lot more than you think.