Hi guys,
Started getting into cycling this summer and have spent hours researching for my bike and possible upgrades. Here is my story and I hope you guys can help me get riding a lot more.

So I have a Univega Viva sport from 1985 with pretty much original components which I traded a set of old summer car tires for about 6 years ago. I rode it a few times but mostly it sat. I fixed it up this summer...wiped it down, greased chain... that's about it and started riding.

Ive been doing 20 mile rides flat surface at avg 15mph about 2x a week but would like to increase this.

I started researching road bikes and fitment options and found my bike is a 58-59cm by my measurement, probably a 58cm. Im 6'4.5 and just a hair under a 38" inseam, weight 190. So I went to the LBS and poked around, they said I should be riding a 63cm frame but 61cm is the biggest road bikes they make now a days and showed me their lowest cost Specialized road bike for $750. I'm in school and cant afford that, realistically $400 for a bike is my max and free seemed great till I realized it was the wrong size.

To get my bike running well and "properly" fit I would need to buy a new seat post and quill stem as the ones I have are too short. Then I would have to rebuild my bearings I assume both wheels, bottom bracket, new saddle, chain, and tires.
or
Sell it and buy another bike. I looked at giordano libero 1.6 61cm new and it seems like a possible choice or scour craigslist for a entry level newer bike that someone is selling for 300-400. If Im buying a bike I would like it to be on the newer side not another 80-90s racer.

I also like tinkering and building things from scratch, (cars, go karts, guitars) so that isn't much of an issue if it saves money. I would rather buy tools than buy labor.

Let me know what you guys think and any help would be appreciated.

I'd head over to the Classic and Vintage forum and ask about good quality used bikes. They can help you out.

80's, 90's Japanese bikes are what I'd be looking at. They get overlooked in many markets but are high quality.

bbattle has some good advice (not that I know much about old Japanese bikes), though you did say you'd like something newer. Cannondale makes their CAAD10 in 63cm, though that's out of the budget. However, you might check to see what kind of used Cannondales you can find in 60cm and up.

Finding good used bikes in the 60cm+ range seems like it's tough (at least whenever I look). I don't come across too many when browsing around online, especially compared to 58 and 56cm bikes.

Also, how do you feel on your current bike btw?

Yeah the 61+cm isnt making life easier. I feel ok on the bike but both seat and stem tubes need to be replaced and raised up for the fit to be correct, which I'm hesitating pulling the trigger on or putting the money towards a different bike.

You could try to hold out and ride your current bike for a few more months and save for a better bike. If you can save and afford a bike closer to $1k, you should be able to get a pretty nice used bike like a CAAD10 or maybe a new Fuji with aluminum frame and 105 components.

So I would agree with you except, saving only happens when you are making money. When I finish school in 2 years I plan to get ~1000 bike when I have a real income. 2 years on my current bike seems like a long time if I want to try to get into the sport more intensely.

Craigslist? It may take a little while to find the right size...

Thanks for the responses, so what size should I be looking for. LBS said 61" for a newer bike is fine but they calculated my frame size as between 63 and 64. Again Im 6'4.5" and 37.5 iinseam. Will the size change between a newer style and older style frame?

I would watch Ebay. You should be able to sort or search by frame size. I bought the bike I am riding now there for about $500 bucks. It was a bike that was originally a $1000 MSRP bike, and had been sitting in somebody's bike shop for 2 years unsold. So I got a brand new $1000 bike for half price because it was 2 model years ago. If you check your LBS, they may have a few of those around as well.

Unfortunately, the price range for new bikes with decent quality is around the following:
$400: Upright hybrid
$800: Entry level road
$1,000: Entry level cyclocross

The only way to do $400 is to buy used. Wrong size is the #1 mistake I see people make when buying a new bike.

Thanks for the info. So ideally I would want a entry level road bike used . What would my frame size be since the LBS gave me somewhat conflicting information: I was size for a 64cm bike but 61cm is all that is currently make without special order in that price range he said. Thanks