# Giant XTC JR 24 disc and loosing some weight?



## Chillout (Sep 19, 2010)

Hi, I just purchased a Giant xtc Jr 24" disc for my 7yr old. So far it's been great. I weighed it though and I got 28.8lbs. Any suggestions on how I can get it down a bit without sacrificing the ride quality and spending a ton?

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## lem2 (Mar 2, 2008)

Hi! Yes it is heavy. I managed to dropped it down to 25. I changed the wheelset, cranks, cockpit and fork. Removing the stand is 1lb already. You can see what I did a couple of threads down. My son is 7 as well! 


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## lem2 (Mar 2, 2008)

In case later on you will decide to do 1x9 or 10. The BB needs to be changed to 108 to get a better chain line. The stock is 114, to wide to use for 1chainring up front.


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## Chillout (Sep 19, 2010)

What fork did you use on your sons? Wasn't planning on changing that but if I found a cheap upgrade then maybe.

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## POAH (Apr 29, 2009)

lem2 said:


> In case later on you will decide to do 1x9 or 10. The BB needs to be changed to 108 to get a better chain line. The stock is 114, to wide to use for 1chainring up front.


thats not true, BB width is determined by the type of crank you use. a standard low profile square taper needs a 113mm BB for a normal chainline i.e what shimano use for their 1x11 systems. Lewis's ripcord uses a 113 with his 1x11 with no issue.


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## Chillout (Sep 19, 2010)

I bought the bike because it had front suspension among other things. If I wanted a rigid fork I could of saved quite a bit. It seems heavy in the ass end so probably the crank. My son also likes the kick stand... I'll see what I can drop. 

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## GSJ1973 (May 8, 2011)

Chillout said:


> My son also likes the kick stand... I'll see what I can drop.
> 
> Sent from my SM-N900V using Tapatalk


Carbon fiber kick stand maybe? 

I am a firm believer that anything that you can upgrade that rotates will make your kid faster before non-rotating components.

Typically on a stock bike in this order...

New wheels
Lighter tires (set up tubeless) Schwalbe Rocket Ron and Kenda SB8 are lightest
10 speed cassette/shifters/rear derailleur
Cranks (1x setup)
Lighter Bars, stem, seat post

The above should drop at least 4 pounds, but be prepared to spend $600.00+ unless you have take-off parts already which you very well might.

Wheels/tires set up tubeless will be the biggest upgrade in both weight and reduced rolling resistance for a young/light kid but also the most costly. It's where I started and I dropped about 2.5 pounds alone over stock setup.

Riveted 3x cranks I saved 200 grams.

Handlebars, stem, seat post were all steel OEM and I dropped another 600+ grams.

Steve-XtC started a great thread here with some really helpful info for mods: http://forums.mtbr.com/families-riding-kids/kids-offroad-bike-weights-component-1006850.html

Happy modifications!


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## lem2 (Mar 2, 2008)

POAH said:


> thats not true, BB width is determined by the type of crank you use. a standard low profile square taper needs a 113mm BB for a normal chainline i.e what shimano use for their 1x11 systems. Lewis's ripcord uses a 113 with his 1x11 with no issue.


Well I tried the stock bb that came wih it. 1x9 the chain would always detail at the 36t cog even with spacers the only recourse was to change the bob from 113 to 107.

And I was using a different (non Shimano/sram) crank. Later in I saw that if I was to use it as 1x set up I have to change the BB to 107. 









Thats what my lbs did.


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## POAH (Apr 29, 2009)

Lewis has a thorn crank, thats infomation is incorrect


the stock BB on lewis's old blast was 122 as the crank wasn't low profile. You couldn't use the thorn crank on that or the chainline would be too big.


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## lem2 (Mar 2, 2008)

POAH said:


> Lewis has a thorn crank, thats infomation is incorrect
> 
> the stock BB on lewis's old blast was 122 as the crank wasn't low profile. You couldn't use the thorn crank on that or the chainline would be too big.


If you say so. 
But that's what I did(my lbs) to make it shift through all the nine gears.


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## POAH (Apr 29, 2009)

lewis's shifts through all 11 gears and 10 before that - there must have been something wrong with your set up or frame.


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## lem2 (Mar 2, 2008)

POAH said:


> lewis's shifts through all 11 gears and 10 before that - there must have been something wrong with your set up or frame.


Lewis has the same frame?


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## POAH (Apr 29, 2009)

no lewis doesn't have the same frame but unless the Giant has some weird rear OLD the spacing for the BB should be the same for the thorn crank.


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## Mark194 (Mar 3, 2012)

grab a RST first fork from Bike discount in germany, $140 bucks and it saves almost 2lbs. Also, get some spectra cranks for 40 bucks on ebay, 500 grams with a single ring. check out my son's Giant here, just over 20lbs...


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## lem2 (Mar 2, 2008)

Wow!!


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## Steve-XtC (Feb 7, 2016)

Flucod said:


> Had my daughters 24" (few years back) down to 19lbs, but it was not cheap. Getting the weight down and cheap usually does not work.
> 
> Bar, stem, seatpost, saddle are the cheapest place to start. Rigid fork, crank, wheels, cassette would be next on the list. If I remember, ended up spending about 1.5k into upgrades.


By far the best bang for the buck is the kickstand.
As you say the bars, stem, seatpost are all VERY cheap to replace.

I paid $30 or less for carbon bars and a much lighter fork...
We don't have the disk model Giant in the UK so specifics I can't say...

I've yet to see most bikes with the correct (or even close) crank length. 
Dropping the 3 ring suntour for a SRAM S600 I cut down and single NW chainring dropped a lb by itself ... before even taking into account shifter and front mech

After that it depends on the hubs. 
If its a cassette then that's one path that *needn't* involve changing wheels
If it's a freewheel then its a different story.



GSJ1973 said:


> Steve-XtC started a great thread here with some really helpful info for mods: Kids OFFROAD Bike Weights by Component


The thread has 2 main reasons (so far as I was concerned) but both are really to enable parents to take a more holistic view.

Ideally this should be a way to plan BEFORE you buy... (I didn't but hopefully some can)

Secondly, its the mean to be a resource for those who already bought and want to work out where and what they can upgrade and how much weight that might save and what else is affected. Costs will obviously vary depending if you have a spares bin or are buying used parts, only buy heavily discounted items etc.


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