Upgrading a Mongoose Disturbed 21spd MTB bike.?

Question

Hello, I'm trying to upgrade my Mongoose Disturbed MTB bike I purchased cheap for $178 at Canadian Tire.

I would like only serious, helpful suggestions for upgrading the components on this bike on a budget. I know that this is a "dept store Mongoose" and Mongoose sell really good "real" MTB bikes. The frame on it is quite heavy, but the welds look well done and strong. My bro races competitvely XC, on his expensive Kona custom, so I can ask his advise too. But he lives in another city from me.

It has pretty much the lowest components possible on it(ie taiwan parts.)

Zoom Dirtech XC front suspension(generic A28 model) It's not on their website though.

http://www.hlcorp.com.cn/hlqc/pro.asp?LarCode=HLQC&MidCode=ZOOM

Lu Jin rear shock LJ 400ax(This has an usual Eye to Eye length 6.25, which makes an upgrade almost impossible)

http://www.diytrade.com/china/4/products/571809/SHOCK_ABSORBER_LJ-400AX.html

Promax front mechanical disc DSK400 brakes. ASPE(taiwan) rear linear v-brake/levers.

http://www.promax.com.tw/english/disc_brakes.htm

http://www.apse.com.tw/E/body.php?web=11&SNo=02&FNo=101

No-name front derailleur and DNP Epoch 7 rear derailleur/13-28t slick system freewheel. I could not find any info on DNP online. Velo Shift VS-030 grip shifts. Could not find any info on these either.

Other parts are no-name Cane Creek headset, mongoose bars, stem, cranks, seatpost etc,

I have already rode it a couple times, and adjusted the shifting to where it's "as good as I could get it", and it rides pretty good. No bobbing with this rear shock design that I could tell. I'm pretty light though 130lbs. Front fork is adequate, ran straight over curb and it didn't bottom out. I adjusted the Disc brake, so it doesn't rub, and it can lock the front pretty easy.

I'll be using it mostly on road and maybe light XC trail. Hardly any stunting/jumping.

I have already ordered online a new 2007 RockShox Dart 2 front shock cheap for $80, which should help that Zoom. I'll get a local LBS to install/tune up and check my bike out.

I wanted to know what/if any drivetrain/shifters I can replace the DNP Epoch 7 system with? Freewheels are getting rarer, but still cheap to buy. Also, I wanted some better/lighter rims&tires. If I replace the rims, would I also need to change my rear cogs/drivetrain?

It has no quick release skewers at all, so if need be I'd pay to get disc compatible hubs&QR with the new rims. I will also want better "cheap" pedals, maybe Truativ Crankset/Bottom Bracket, better front disc brake, rear v-brake etc.

I will be going to the LBS and get their advise too before I decide what to do/buy. I want to plan my "rebuild" over the winter on the cheap. Finding the right parts online would help keep costs down.(pricepoint, nashbar, jensonusa, harris cyclery) But, if just getting the LBS to upgrade slowly or all at once would be the best option. I can take pics of the bike, if it will help.

Thanks to all who reply with their advice and help.

Answer 1

Um, rather than make suggestions on upgrades, might I outline some problems that you might run into as you go along?

1) Going to quick release on the rear wheel will not be possible since the dropouts are too thin. Grinding down the axles to fit or adding a spacer behind the locknuts is not a good option. If you change the wheels make absolutely sure you get a Shimano compatible 7 speed freehub and cassette to replace the freewheel.

2) You might need to get a rear derailleur with a hanger attached. If you really want to do this, go to Shimano Alivio or Deore... there are hangers available but they are not common. You'll also need Shimano shifters and freewheel for proper operation. DNC is a very low end Chinese company that uses worn out Shimano tooling. Right now, I think, they are using Shimano Eagle, Lark, and Crane tooling from the 70s.

3) I am pretty sure (but not positive) that your bike has a 1" steerer and the Dart 2 is 1-1/8". Not compatible. The Zoom Dirtech is an "original equipment manufacturers" offering and not available to the general public. These are used on very cheap bikes,especially those with head tubes under 120mm long. By the way... no Rock Shox product will be compatible with a head tube under 120mm.

4) Placing a more aggressive rear shock in will destroy the plastic pivot bushings, so if you choose to do so, pull a bushing out before they get worn and get bronze replacements at a shop that carries bearings.

I will make only one suggestion. Before you start on this upgrade "on the cheap" do some quick searches for parts prices. It is not uncommon for you to be able to get a new, better bike for the cost of such a comprehensive upgrade. If you are digging the idea of this, go for it but be well advised that you won't be saving any money.

EDIT: This is an OEM site http://www.biketaiwan.com/2008TBS/tbs/tb... so you won't be able to see pricing but you can do a search for the raft of garbage parts available- as well as good stuff.