# Motocross brakes on your DH bike. Pros and cons.



## Davidcopperfield (Jan 17, 2007)

Hello
What are the positives and negatives of using MX brakes on DH bikes? How actuallly do the brakes differ from each other?
I know that some DH brakes have 4 pistons and how many pistons do MX brakes have? I know that MX brakes' rotors are more than 210mm perhaps 300mm. Maybe you some site where they are compared?


----------



## Rover Nick (Jul 13, 2006)

That sounds like a great idea, since MX brakes are designed to bring a 400+lb moving object from speeds of 50-60+mph

I guess you could make it work, but it could be kinda pointless. Its kinda like putting an MX fork on your bike


----------



## Err (Mar 21, 2005)

I really doubt you need more than a Gustav or a Moto V2 or even a Code. In fact, I think some of the more powerful brakes on the market may be a bit too powerful. The idea is that too much power just leaves you locking up one or both wheels way too much which make for slow riding and poor control. You'd have to be a combination of a very heavy rider, with very poor braking skills to make the current crop of big brakes fade.


----------



## Internal14 (Jan 21, 2004)

I couldn't image how jacked I'd get if I took the brakes off my KTM and threw them on my DH bike. They stop 500lbs(me and bike) like nothing flat, with one finger.

Super overkill.

I have some Hope MotoV on my 7" bike and they are sometimes too much already.


----------



## HighTitan (Jan 26, 2007)

pointless, if you need MX brakes on your DH bike you shouldnt be ridin DH. let off your brakes and rip it. no need for super powerful brakes. and plus thats added weight you dont need.


----------



## kuksul08 (Oct 8, 2006)

Dirtbike brakes weigh about 20 times as much, and bicycle brakes are definitely good enough.


----------



## 08nwsula (Oct 19, 2005)

[email protected] said:


> yeah might as well put plane engines on our lawn tractors....


----------



## thatdownhillkid (Mar 11, 2007)

why not those gator brakes with the 8 pistons. those probably are almost mx brakes anyways. and mx brakes are too heavy. they would probably weight close to 5 pounds a piece. so take your already 40 pound bike and make it 50. besides being able to have no modulation at all. your either off the brakes or both wheels are locked up.


----------



## Davidcopperfield (Jan 17, 2007)

thatdownhillkid said:


> besides being able to have no modulation at all. your either off the brakes or both wheels are locked up.


Well there was a guy who used mx brakes on dh bike and simply tuned them and had good modulation. For sure it give you more power with 280mm or 300mm rotor. That guy even used mx fork. 
So you generally do not see advantages? I heard that some dh bikes blur the difference between bike and motocycle.


----------



## Dogboy (Jan 9, 2004)

Davidcopperfield said:


> Well there was a guy who used mx brakes on dh bike and simply tuned them and had good modulation. For sure it give you more power with 280mm or 300mm rotor. That guy even used mx fork.
> So you generally do not see advantages? I heard that some dh bikes blur the difference between bike and motocycle.


What a bunch of utterly ridiculous nonsense.


----------



## Heals120 (Apr 16, 2006)




----------



## gil_caz (Jul 12, 2006)

Heals120 said:


>


nice... supermoto here i come!


----------



## tacubaya (Jan 27, 2006)

Heals120 said:


>


Holy fack, thats the most retarded thing I've ever seen :eekster: :skep:


----------



## KavuRider (Sep 22, 2004)

y'know, I'm all for long travel and big tires.
However...there is a limit.
At that point...buy a dirtbike. 
OR...heck, give it a shot and then tell us how it goes.


----------



## RaindogT (Oct 2, 2005)

[email protected] said:


> yeah might as well put plane engines on our lawn tractors....


Now that is REALLY an interesting idea....
Jake, you are a damned jeenyus!!!!


----------



## lelebebbel (Jan 31, 2005)

EDIT: damn, I got trolled!

Read the OPs other posts. He has quite a history of great ideas.

Davidcopperfield, here's some inspiration for future projects:

-- Bicycle chains are way too flimsy. Do you think there is a way to run these to a bike?








How would one have to modify a regular 9 speed derailleur to run them?

-- Ejection seats on DH bikes. People are doing jumps 30ft plus, wouldn't it be great to have some sort of safety system? Is the "Martin Baker WY6AM" available with a 31.6mm seatpost?


----------



## Rover Nick (Jul 13, 2006)

I'm pretty sure that chain is only available in an 8 speed

Anyone ever hear about that guy that made a paper shredder out of a hemi? It was able to do state-wide phones books for breakfast


----------



## Rover Nick (Jul 13, 2006)

Like I've said before....Don't feed the 29'ers


----------



## rm_racer (Feb 3, 2006)

Davidcopperfield said:


> Well there was a guy who used mx brakes on dh bike and simply tuned them and had good modulation. For sure it give you more power with 280mm or 300mm rotor. That guy even used mx fork.
> So you generally do not see advantages? I heard that some dh bikes blur the difference between bike and motocycle.


dude, you have to be kidding me. the brakes on my 250 probably weigh 5-6 pounds. each. yeah, they will stop well, but dude, 10-12 pounds of brake? and a 270mm rotor up front? that will put 200 pounds past the front wheel in a heartbeat, assuming the tire will be able to hold onto the ground long enough. with a motorcycle brake's power, you would only need a 6 inch rotor to get too much power on a bicycle. a motorcycle weighs almost 6 times as much as a bicycle, so the added power is needed and the weight is negligible. if i only need to use one finger when riding my motorcycle, if i breathed on the lever it would stop the bicycle. one more thing, the drag from the pads on the rotor would slow you down in addition to the extra 10 pounds on the bike.

and the guy with the mx fork too probably had a 70 pound bicycle. plus you have $110 to re-spring the front end for a bicycle weight, then the forks are over-damped. kind of an expensive way to add weight.

yes, some DH bikes do sort of almost start to blur the line between motorcycle and bicycle, but those are the ridiculously outlandish bikes that weigh 60 pounds and have the bottom bracket two feet in the air.

sorry to be harsh, but that's how it is. no advantage to running a motorcycle brake on a bicycle. none. zero.


----------



## AmPb100 (Jul 13, 2006)

Dude get a pair of Gustavs.


----------



## NWfreeride (Jan 23, 2007)

Our Original Poster also posted a thread entitled "Motocross forks for 29ers possible?... I am simply amazed... really.


----------



## kenbentit (Jan 2, 2003)

Just because something is possible doesn't mean it should be done...


----------



## rm_racer (Feb 3, 2006)

NWfreeride said:


> Our Original Poster also posted a thread entitled "Motocross forks for 29ers possible?... I am simply amazed... really.


is it possible to put my dad's spare KTM rear shock on my Jamis Dakar XLT? i might have to re-weld some mounts, but it hink it would be plusher and have more travel. not too much extra weight either.


----------



## tacubaya (Jan 27, 2006)

It would be pretty sweet, I guess the rear wheel would explode when you bottom the shock


----------



## thatdownhillkid (Mar 11, 2007)

how much stroke do mx shocks have? 5+ inches?


----------



## rm_racer (Feb 3, 2006)

yeah it would almost definitely explode the rear wheel. i wonder when Push will start doing WP shocks. or maybe i could get them to do the KYB shock from my brother's bike :thumbsup:

mx shocks have something around 4-4.5" stroke.


----------



## thatdownhillkid (Mar 11, 2007)

dude. if motocross bike are running like 3:1 ratios than bikes could run like 6:1 ratios to make up the weight difference. a bike with 2+ ft of travel.


----------



## S_Huitt (Jun 23, 2007)

Urban Downhiller!!! Corners like a mo' fo'!!!


----------



## Secace (Sep 8, 2004)

That chain is massive. Almost as big as the one I lock up my bikes with.


----------



## Ace1 (Jun 14, 2004)

I was talking with some Hope representatives at at the London Cycle show (trying to ascertain where they saw the mono 6 Ti sitting in the product line after the introduction of the moto V2).

They told me that what they've been working on with quite a few of the riders that they've been working with this past season was how to reduce the power of their brakes. Apparently the moto V2s are out of the question - their race riders use either mono 6 Tis or mono 4s and they've been experimenting with smaller piston diameters, smaller discs and even shorter levers so that the riders have the modulation without so much power that the wheels (particularly the rear obv.) just lock up as soon as you're on the brakes.

A lot of brake development and one-up-man-ship in terms of power is marketing.


----------



## ducktape (May 21, 2007)

> Hello
> What are the positives and negatives of using MX brakes on DH bikes?


I reckon this is the sort of question that probably led to development of hydro discs for mtb.

I do agree with everyone else, for a start they would be way too heavy! I've only seen the levers /calipers / rotors on a Suzuki DRZ250 and did kind of compare the tech to the ones on my MTB. It's just so similar but in a bigger scale.

If you really want to experiment, I'd take a set of powerful MTB disc brakes and put them on a moto to see how they fare!


----------



## Gravity Assist (Aug 18, 2007)

HighTitan said:


> pointless, if you need MX brakes on your DH bike you shouldnt be ridin DH. let off your brakes and rip it. no need for super powerful brakes. and plus thats added weight you dont need.


 I like the way you think man. You are apsolutely right.... you don't want to stop, its bad!

MX brakes on a DH bike (assuming you would even be able to mount and line up something that rediculous) is pretty dumb. *It sounds like a 1-way ticket to a broken collar bone.*:eekster:


----------



## Gravity Assist (Aug 18, 2007)

Since we are Bluring the line between Moto and DH, with stupid ass moto brakes, why not totally F^ck it away and add these! Is 203mm not enough for you?? try 265mm to 300mm? **** it, strap a motor on that F^cker too..why not.


----------



## Gravity Assist (Aug 18, 2007)

Ok, maybe I got a little carried away. Food for thought, at first, people wanted to add Moto Hydro's to bicycles, but couldn't which is why Hayes, originally put them out... for those of you who have been around in the sport long enough to remember the PURPLE HAYES brakes, almost a straight off mimic from a Moto, but compared to the brakes we have today, the purple hayes, suck... because now they have brakes that are not only powerful, but light... more MTB specific...why would you want to go backwards....


The only thing you should really use off of Dirt bikes for DH/FR is their jersey's and helmets, gear,etc...things like that. Maybe fork oil, since you can get it for loads cheaper from them as opposed to the MTB companies. But its not like a lot of stuff on the DH/FR market doesn't greatly mimic Moto-cross components enough already... I guess the human brain is never satisfied.


----------



## tacubaya (Jan 27, 2006)

I've used a dirtbike with a Motocross Shiver up front.... felt right at home 

Now watch this (look at the back brake.... looks familiar?)


----------



## gil_caz (Jul 12, 2006)

ha ha ha.. i was just about to bring up fx bikes. they have motors weigh around 100-110 lbs and use hopes and ive seen early production models with formulas. rode the proto not to bad of braking on it, i just dont know where i would use that. nice addition to the convo.


----------



## Gravity Assist (Aug 18, 2007)

that Dirt bike looks sick! what type of bike is that? Do you have MtB tires and rims on it? it looks pretty revolutional...


----------



## creyc (May 24, 2005)

That thing looks downright fun! What engine is that?


----------



## tacubaya (Jan 27, 2006)

Engine choices:
» FX Honda-Replica 125cc (auto-clutch or manual clutch)
» Honda Daytona 88cc Big Bore (manual clutch only)
» Honda Daytona 119cc Big Valve Head-Kit 4-speed (manual clutch only)

It uses Downhill rims, handlebar, fork, hub and sometimes brakes.

Its a lightweight dirtbike, weighs around 110lbs..... fusion between dirtbike and downhill.... I want one!!!!!!


----------



## rm_racer (Feb 3, 2006)

've seen bikes like that from a company in NZ that made their bikes with ti frames. they had fox 40s on the front, deemaxes, and hope brakes. they looked pretty damn fun. 

i like the two-stroke pipe on that engine in the bike tacubaya posted lol.


----------



## Rover Nick (Jul 13, 2006)

http://marzocchi.com/template/detai...LN=UK&Sito=moto&mCO=&mCW=&mCJ=&IDOggetto=8874

Left leg weight: 5040g (11.1lbs) 
Right leg weight: 4948g(10.9lb)

So were talking 22lbs NOT including crowns and steerer


----------



## SHIVER ME TIMBERS (Jan 12, 2004)

Err said:


> I really doubt you need more than a Gustav or a Moto V2 or even a Code. In fact, I think some of the more powerful brakes on the market may be a bit too powerful. The idea is that too much power just leaves you locking up one or both wheels way too much which make for slow riding and poor control. You'd have to be a combination of a very heavy rider, with very poor braking skills to make the current crop of big brakes fade.


agree...would add Saints


----------



## Davidcopperfield (Jan 17, 2007)

Here you have 6 mounts MX brakes 
http://www.edelbrock.com/offroad/mc/rotors/ if you tune it correctly you will get marvellous heat dissipation and modulation.
I would use these 270mm rotor front
http://www.motocross.com/articles/article/news/20070927/braking_270mm_front_brake_kit-4201.html see the film.


----------



## nano5467 (Jun 2, 2006)

moto parts on a dh bike makes less sence then even this


----------



## rm_racer (Feb 3, 2006)

Davidcopperfield said:


> Here you have 6 mounts MX brakes
> http://www.edelbrock.com/offroad/mc/rotors/ if you tune it correctly you will get marvellous heat dissipation and modulation.
> I would use these 270mm rotor front
> http://www.motocross.com/articles/article/news/20070927/braking_270mm_front_brake_kit-4201.html see the film.


do you have any IDEA how big mx hubs are in comparison to mtb hubs? the fact that it has 6 holes won't do it. then you want to go with a 10.5" rotor? are you nuts? my motorcycle has a 10" rotor and it more than gets the job done.

then, how would you go about tuning a motorcycle brake for mtb? wd-40 on the rotor and pads? i would really like to know. you can't really "tune" motorcycle brakes. yes, they have great modulation....on a MOTORCYCLE. a 400 pound payload. cut that in *half* and you have the payload of a bicycle and rider.

i beg you, don't do this! you will have a 60 pound bicycle and the first time you ride it you'll end up in a sling for the next month with a broken collar bone.


----------

