# Beginner - Dirt Jump Bike conversion



## xZach (Sep 18, 2011)

So I've been riding trails for about a year now. About 4 months ago I picked up a canondale f6. Recently I went to a friends house and did a couple of his dirt jumps. I've now found a love for dirt jumping :thumbsup: but my F6 just wont do as is. I've got a few questions.

1. What does converting to single speed help do?
2. Are there any necessary mods I need to do to get my bike dirt jump ready?
3. If yes to #2, what do I need?

Also , any suggestion on a new front brake? Mine sucks. I've had so much adjusting but it just keeps locking.


----------



## cmc4130 (Jan 30, 2008)

xZach said:


> So I've been riding trails for about a year now. About 4 months ago I picked up a canondale f6. Recently I went to a friends house and did a couple of his dirt jumps. I've now found a love for dirt jumping :thumbsup: but my F6 just wont do as is. I've got a few questions.
> 
> 1. What does converting to single speed help do?
> 2. Are there any necessary mods I need to do to get my bike dirt jump ready?
> ...


1. People choose singlespeed because it is simple, durable, chain doesn't rattle around, and you don't have to worry about bending derrailleur etc.

2. In general, it's better to have a dirt jump specific bike, rather than converting an xc bike, but if it's a small frame xc bike, you can still do some things to make it more jumpable. the main thing is getting a DJ/BMX stem. the reach will be 40-50mm.

3. Front brakes.... most DJ riders don't use 'em.

A couple of typical DJ bikes.

_Specialized P1_









_Blackmarket Soldier_









check out the look of the DJ bikes out there:
https://forums.mtbr.com/urban-dj-park/pic-posts-only-no-discussion-lineup-2010-11-complete-dj-urban-mtbmx-bikes-707301.html


----------



## too many components (Nov 6, 2012)

I've gotten a trek 4300 (13") and I'm thinking the same thing.

I have $120 to spend on converting it to singlespeed 

What components should I buy?


----------



## NEPMTBA (Apr 7, 2007)

IMO...

...Don't bother trying to convert a mt bike into a DJer, angles are wrong and won't get the performance out of it. Plus basic mt bikes aren't meant for jumping. You will be better off saving for a DJer in the long run, and it will help you learn the correct way to ride rather than trying to horse a mt bike over stuff!

Just my 2 cents

Haro makes a good entry level DJer


----------



## cmc4130 (Jan 30, 2008)

too many components said:


> I've gotten a trek 4300 (13") and I'm thinking the same thing.
> 
> I have $120 to spend on converting it to singlespeed
> 
> What components should I buy?


Does it look like this? :









What's your height/weight/age? If you're actually the intended audience for that bike, then maybe just continue riding it with some modifications.

If you're a taller dude that is trying to just find a small DJ-ish bike to ride, then don't! Sell the Trek and put your money with the 120 and buy a used complete of something more suitable.

The issues are that 
(1) The fork is not made for jumping. At some point it will just SNAP, which will be a really bad crash. You won't get your hands out in front of you cuz your hands will still be on the grips and you'll face-smash on the ground.
(2) The frame is not made for jumping--or at least for an adult-weight male jumping.
(3) The front end is very short. Yes, the seat tube height (13") is similar to DJ bikes, but in the xc world, when the seat tube is low, they make the front end shorter too. It's designed for short person. DJ bikes on the other hand, will have a front end length that is similar to a typical 16", 17", or 18" xc bike (i.e. 21.5", 22", 22.5" actual top tube).

A much better deal for the money would be something like a 2010 DK Cygnus 24" bmx. They go on craigslist around here for around $150. They were about $350 new. You get an all-chromoly frame and some pretty solid parts. The reason I'm saying 2010 is because in 2012, DK started a line that is sold through Walmart and I doubt the Walmart DK's are up to standard.

:









_2010 DK Cygnus 24

Frame: DK 24" Park/Trail design *100% 4130 Chromoly*
Fork: 100% 4130 Chromoly steer tube (1-1/8")
Handlebar: DK Cruiser 2 pc
Grips: DK Tsuka
Stem: DK Alloy 1-1/8" Top Load 
Headset: 1-1/8" threadless 
Brake: Tektro Alloy U-brake (seatstay mounted) 
Cranks: Tubular 3pc 175mm Chromoly 
BB: Mid w/ 8 splined Chromoly spindle 
Pedals: Alloy Platform 
Sprocket: DK 33T 
Cog: 15T Freewheel 
Chain: KMC 
Wheels: Alloy 36H rims w/Alloy hubs 14mm rear axle
Seat: DK Slim 7mm rails
Post: Alloy 25.4mm
Tires: Kenda Multi surface, 24"X 2.1" front & 1.95" rear 
Accessories: N/A
Color: Clear / Green
Top Tube: 21"
Chain Stay Length: 15"
Head Tube Angle: 73.5 degrees
Seat Tube Angle: 72 degrees
Weight: 27.3 lbs.
_


----------



## chain_slap (Aug 28, 2008)

For $120 you could get a Truvativ Husselfelt 40mm stem, Husselfelt riser bars, generic cog & spacer kit, and generic tensioner. Lose the front brake. As long as you are hitting table tops, rollers, and small berms you should be fine. Large gaps and step ups should come later with a better bike. Keep everything you take off the frame so you can barter, trade, or pay it foward. 

Go to your local bike shop and tell them you have a budget for the single speed conversion. Sometimes they have take off parts or the mechanic has his own stash they might sell cheap. 

Above all wear a helmet, if that frame snaps its going to hurt.


----------



## Tone's (Nov 12, 2011)

Dont bother with the convert, you need a purpose made DJ bike if you wanna have a go.
DJ bikes are made to take some serious abuse, an ex XC bike in no way shape or form is made to use as a DJ bike.
Dj bikes are cheap, you can pick up one that will put you right in the game new for 1k or find a very nice second hand one for 400 bucks, dont risk serious injury converting a bike into a DJ bike, its not a good idea, you will still have to change the wheels, cranks, bar, stem, tyres, fork and youll still have a bike thats not up to it and you would have spent as much as you would have to buy a new bike.
Ive got a giant STP, its a nice lil DJ bike, you can pick up a bike like that now for 400bucks second hand and then you can really give it a crack, cheers


----------



## Tulok (Oct 9, 2012)

I threw an RST Mozo R500 on the front of a 13" trek like yours, with a shorter, lower stem and its not bad. but unless you get the fork for free (and double wall wheels, crank and steel bars and etc etc etc) I would just keep on riding it until I saved up $250 for a used bike. It does jump pretty well though and its easy to throw around, though I'm 6'3".


----------



## ronnyg801 (Oct 4, 2008)

Save your money for a used DJ bike, Keep an eye out on here, pink bike, craigslist etc... You will be far happier in the long run.

get resourceful on the internet, there are tons of sites that sell completes too, often at closeout prices for last years model, which is often just a colorway difference


----------



## 50calray (Oct 25, 2010)

ronnyg801 said:


> Save your money for a used DJ bike, Keep an eye out on here, pink bike, craigslist etc... You will be far happier in the long run.
> 
> get resourceful on the internet, there are tons of sites that sell completes too, often at closeout prices for last years model, which is often just a colorway difference


This,

I'm thinking about pulling the trigger on a used DJ bike I found here locally on Craigslist. It's dirt cheap (pun intended ) with room for improvements should I really take to the style. So check out eBay, Craigslist etc etc first and save your XC for trail riding.


----------

