Rebuilding a mountain bike?

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Rebuilding a mountain bike?

StevenRB45

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I'm looking towards the end of uni and something to do to make the inveitable prolonged job hunt pass faster. So i want a little project for over summer. I've been wanting a nice hard tail mountain bike for while as current full sus bike is ridiculous if you aren't on rough ground and a cow to jump. Recently remembered I have a GT aggressor 3.0 in the shed and thinking about doing a rebuild on it.

There are some problems however...
1: I haven't taken a bike apart in ages and know nothing (should make it interesting learning tho)
2: Despite only two years of actually use and another 2 laid up the GT is ruined. Worst bike I ever had hence why I forgot about it. I gave up on it when the crank snapped in half but before then it had 3 new back axles (also one on it now appears to be broken) and the forks were trouble too.
3: Not really sure what new bits to buy

So thinking about taking it apart, getting new forks for it (possibly a new headset too), new crank and bearings, new wheels and tyres, probably leave the current gears on the back and just go for a single speed chain ring at the front. Not sure about the brakes new forks will have mounting points for discs I assume so I could go for a front disc but there are no mounting points at the rear as it pre-dates discs being common place so probably have to stick with a V brake but a better quality one would be good. The current ones are plastic and bend IIRC :rolleyes:

Wondering what sort of stuff to get, Marzochhi Bomber forks are good in my experience (my full sus bike has them) but open to other suggestions. Also a fan of Tektro IO cable operated discs from my current bike, and they are more suited to my skill level. Other than that dunno what to get...er help?

That and wondering if GT frames are all the same or theres no point in doing this to one that was sold with lots of crap attached to it as the frame is also crap..
 
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I'm looking towards the end of uni and something to do to make the inveitable prolonged job hunt pass faster. So i want a little project for over summer. I've been wanting a nice hard tail mountain bike for while as current full sus bike is ridiculous if you aren't on rough ground and a cow to jump. Recently remembered I have a GT aggressor 3.0 in the shed and thinking about doing a rebuild on it.

There are some problems however...
1: I haven't taken a bike apart in ages and know nothing (should make it interesting learning tho)

This should be a lot of help think of it as the Bible


http://www.parktool.com/repair/bikemap.asp


2: Despite only two years of actually use and another 2 laid up the GT is ruined. Worst bike I ever had hence why I forgot about it. I gave up on it when the crank snapped in half but before then it had 3 new back axles (also one on it now appears to be broken) and the forks were trouble too.

If your mashing cranks and axles you need to spend a bit more on bits " Light, Strong, Cheap " you can only have 2 ;)

for axles i'd always go for hope hubs (you pay for them but i have destroyed a deore hub in under 6 months i have the old Hope XC's for about 5 years and they have had some real hammer and still run as smooth as the day i got them....


http://www.hopetech.com/

cranks something like the new Shimano deore (which come with a bottom bracket) http://www.ukbikestore.co.uk/produc...8/shimano-m532-deore-chainset--bb-483626.html







3: Not really sure what new bits to buy

So thinking about taking it apart, getting new forks for it (possibly a new headset too), new crank and bearings, new wheels and tyres, probably leave the current gears on the back and just go for a single speed chain ring at the front. Not sure about the brakes new forks will have mounting points for discs I assume so I could go for a front disc but there are no mounting points at the rear as it pre-dates discs being common place so probably have to stick with a V brake but a better quality one would be good. The current ones are plastic and bend IIRC :rolleyes:

For the forks this could be fun trying to work out what you have as my 2 cousins have agressors and they both have different spec forks/headsets one is an A-head and the other is a "Quill"

A head has a 5 mm hex bolt on top with a cap and 2x 5 or 6 mm headed bolts right where you smash your knackers if you stop too quick..

a quill usually has a 6mm bolt on the top and thats it


Wondering what sort of stuff to get, Marzochhi Bomber forks are good in my experience (my full sus bike has them) but open to other suggestions.

Rockshox Recon would be my bet (got 2 sets) coil is good even at my light weight 14 stone

but prices have rocketed as of late.... and dont go longer than 100mm forks on that frame


http://www.ukbikestore.co.uk/product/productlist.aspx?dep=85&page=3




Also a fan of Tektro IO cable operated discs from my current bike, and they are more suited to my skill level. Other than that dunno what to get...er help?

well if you want to stick with V-brakes as no rear mount something like shimano deore V-s with deore levers are a solid budget option

That and wondering if GT frames are all the same or theres no point in doing this to one that was sold with lots of crap attached to it as the frame is also crap..

1779660782_5abccb2aff.jpg
 
Its an A head headset then was going to take it apart see how it works..but if its usuable again probably best to know what i'm doing first....need to get a bike haynes....also a spline driver to get the bottom bracket out, current hitting the remaining pedal with a hammer as it refuses to give despite me removing everything that held it on...post up some pics of my 'beast' later..I'd forgottern how light hard tails are tho!
 
bikes are easy, stick to the rule of as you take something apart, keep it in order you took it off.

i was going to do up my mountain bike, but sacked it off as it needed a new rear rim, new cassette, new chain and new front set- priced up £150-£180

so got a newer bike with better frame and components for £250 (when RRP is £380)
 
So true :eek: (n) :cry:

Mad that just as I'm boxing up my FRS to send to the winning bidder - you're thinking of spending £££ on a hardtail GT.

Fate is a cruel mistress.

Yeah but I'm not just doing it because I want a bike...I want to learn how to take them apart and put them back together, this thing has been taking up space in my shed for years and it will make repairs cheaper...got the one remaining pedal off so now off to buy a spline driver...
 
Got my bikes out of storage at the weekend as the house is nearly finished....

Was good to see them....Like old friends!

Can't wait to get back out on them! :D
 
Right current issue is that the lower ball race for the headset is oxidised onto the old forks...its hammer time again...also lost my phone card adaptor so no pics..
 
The 'persuader' and a chisel were necessary but its off now. Fitted a set of Suntour XC forks I had lying about to check I had the general gist of where everything went and they went on ok without any play although they will be coming off again because they are rubbish. Dunno whether to keep that headset :chin: Can't believe in the past I've paid to have forks fitted its a piece of p***. Main issues so far have been corrosion related not looking forward to crank removal as its orange.

The frame itself seems in decent nick tho also it does have rear mountings for a disc brake :woot:

Neway off down to bike shop to price up some bits and get tool to remove the crank.
 
Well got the tools, tried it it fits but omg its jammed tight....given up for the day before I break something/do myself a mischief. Need to figure out a way of doing it! Can't get enough pressure onto socket for it to loosen the damn thing. The socket just falls out when not under pressure so can't use the persuader, same goes for a breaker bar. :chin:

Did notice when down at the bike shop that they are selling 480 quid hard tail GTs...with the same forks as i've just switched onto mine.
 
Well got the tools, tried it it fits but omg its jammed tight....given up for the day before I break something/do myself a mischief. Need to figure out a way of doing it! Can't get enough pressure onto socket for it to loosen the damn thing. The socket just falls out when not under pressure so can't use the persuader, same goes for a breaker bar. :chin:

Did notice when down at the bike shop that they are selling 480 quid hard tail GTs...with the same forks as i've just switched onto mine.


This is where a bit of bodge comes in you need a longer crank bolt iirc its 8mm Metric fine and a washer or 2...

thread the bolt through the BB tool then tighten into the BB axle this then allows you to get a big pair of stilsons on the tool or clamp the tool in a vice and use the frame as a lever and turn (one side is a reverse thread) IE you turn it clockwise to undo
 
This is where a bit of bodge comes in you need a longer crank bolt iirc its 8mm Metric fine and a washer or 2...

thread the bolt through the BB tool then tighten into the BB axle this then allows you to get a big pair of stilsons on the tool or clamp the tool in a vice and use the frame as a lever and turn (one side is a reverse thread) IE you turn it clockwise to undo

My prob is I have half a crank to work which makes every job 3 times more difficult...also bikes been standing for ever again big probs..tbf if it don't go I don't give a s***, no loss i've had the thing forever and learned from it even in 6 hours of trying to get it to bits but want to get it to bits totally and resurrect it..
Buying a new hard tail would be the chickens way out...even if the shop I went for bits from reckons rebuilding an old GT is mental..but I guess they want to sell new ones..

TBF if I went for equivalent i,e, ****e suntour forks and discs it would be 480....so that gives me a budget,..if i get it to bits without f***ing it then thats what i'll aim for.
 
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