GT Aggressor 3.0 my first project

I’ve just picked this GT Aggressor up for the bargain price of £10. It’s a bit rough but that was kid of the plan as I got it so I can learn to strip and rebuild a bike myself instead of getting of paying a bike shop to do it all. The suspension front forks have been removed by original owner for some reason.
So far I have managed to completely disassemble it and get off the seizes drive side crank arm to remove the bottom bracket.

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I now need to order a new BB , crank set , headset bearing rear derailleur.As I haven’t done this before I wonder if anyone can assist with recommendations on parts advice or have and parts for sale that will help get my project back in the road .
The BB measure 68x124 and the headset is 33mm . The free wheel hub is slipping and the wheel bearings are rough so could do with a rebuild.
Need to get a bike specific tool kit as well
 

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If you have anything other than a functioning 8-9-10 speed hub out back, let us know... if not, the most common answer might be "leave it like it is," ie learn to love 3x7. Dig through the bins at the bike co-op for a vintage Shimano bb (and a functioning rear wheel, if necessary) and leave it at that.

If you do have a functioning 8-9-10spd hub back there -- ie if it's just the chain skipping, slowly evolving into an automatic transmission, and not a nasty old knackered hub -- the world is your oyster. Agree re: hollowtech style cranks, you can get em on Ali for as little as $33 US, including bb and chainring. Check out the microshift groupsets, wifey adores her 1x9, it was cheap and an easy install

Dunno how you'd fix a bad freehub. Sometimes you can replace those things, I've had good luck with Shimano freehubs (sometimes you can even upgrade 7spd to 8-9-10spd) but am not sanguine about any other brand

Start with the wheels, take em apart and send us some pics, let's see what you're up against

Far as your headset is concerned. I don't think there's any such thing as a 33.36 head tube standard, sure it's not closer to 33.8? Odds are it takes a standard, plain old 1 1/8 aheadset. I ordered an FSA off Amazon for $25 US and ya know, it ain't half bad. Has those fancy new-fangled "ACB" thingies in there. What'll they think of next, eh.
 
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This model was my first mountain bike! Great to see one still on the go, I gave mine away over a decade ago now! From memory, front forks were inSync elastomer suspension forks so not missing much there.

Weak point I found was the wheel axles, but thankfully an easy replacement as its just a normal cup and cone loose bearing hub. Headset is a standard external 1-1/8" headset. Many brands make them, nukeproof, FSA, Cane Creek etc.

Agreed on the rear mech, If I remember its a shimano altus - very agricultural. Could just need a good clean up and new chain as a first pass along with a check on the rear freehub.

Front cranks - agreed on hollowtech II, easy to install and fine for various sizes based as uses plastic spaces for BB size / chainline
 
Always nice to hear someone is up for learning the art of bike maintenance and repairs.

As said above, you've probably dodged a bullet by not needing to worry about the original suspension forks, they weren't good and we're heavy.

Cranks and rear mech on the bike are also not great, a good opportunity to upgrade and learn about newer standards and frankly better options.

Your rear wheel may limit your options on the number of cogs you can have out back, but if you want to try and salvage the wheels, a strip down and inspection of the cones and bearing races will tell you if they can be saved. Cones and axles can be replaced but if the hub bearing races are pitted, you'll need new hubs, but easier to get replacement wheels unless you are up for learning wheel building.

Freehubs can be replaced depending on the hub, though you may have success in lubing the one you have, as often grease dries up and causes sticking/slipping.

Once you know what needs replacing or upgrading, I'm sure you'll have plenty of willing helpers on here for replacement parts. I've got a lot of stuff that could help, depending on what you need

Most importantly, just enjoy the process of taking things apart and working on the bike. It's addictive and rewarding. If you are buying tools, I'd recommend buying good ones, cheap cone spanners are rubbish, as are most cheap tools, and if you plan on other projects, it's worth getting nice tools initially, as they will be there for you in future, and won't frustrate you and your efforts.

Enjoy.
 
I forgot to take pictures along the way. Im
going to Amsterdam in June and then on to Assen to watch the Moto GP so decided to build it into a bit of a cruiser using new and used parts purchased from EBay .
I put a set of Fairdale low rise BMX bars on with a eBay top loader stem, ODI grips
, Charge spoon saddle, Maxxis DTH tyres , a mix of shimano gear bits . I’ve only been round the block so far but am really happy with the riding position . I have also got a beer rack for the front to go on also 🍻🍻🍻🍻🍻🍻🍻
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