My KDX's front brake is "Weak"

Got questions? We got answers....
User avatar
Oldschool
Supporting Member III
Supporting Member III
Posts: 195
Joined: 05:02 pm Nov 07 2006
Country:

My KDX's front brake is "Weak"

Post by Oldschool »

Hello
All in all My'03 KDX 200 front brake doesnt have near the stopping power
as my last CR did,is that the Norm?
(Minimum effort on the lever to lock up the front tire)

There are Fresh "red" EBC pads on her ...

Thanks
Tony
User avatar
strider80
Supporting Member III
Supporting Member III
Posts: 489
Joined: 12:26 pm Jul 21 2006
Country:
Location: Bothell, WA

Post by strider80 »

Have you bled/flushed the fluid?

I think the stock rubber brake line is a bit spongy too, I can feel mine expand when I squeeze the lever. I am sure a braided stainless line would help.
2005 KTM 250EXC
2000 KDX200 (gone)
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

You have air in the lines....
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
AZRickD
Member
Posts: 524
Joined: 08:51 am Jun 29 2006
Country:

Post by AZRickD »

Mine ('03 220R), has gotten spongy over the last few months. I've bled it and bled it (many ounces worth). It helped only marginally, maybe. On the bright side, I can't lock up my front tire.

I've purchased a way over-priced front master cylinder rebuild kit which I will likely install on Friday.

I'll let you know if I've wasted my money.

Rick
I done KX-ed QuailChaser's KDX220R
User avatar
stringburner
Supporting Member III
Supporting Member III
Posts: 221
Joined: 06:18 pm Oct 12 2006
Country:

Post by stringburner »

My front brake is strong. And please....Its BRAKES, not breaks. Sorry, that drives me a wee bit nuttier than I already am. :rolleyes:
User avatar
Colorado Mike
Gold Member
Gold Member
Posts: 1921
Joined: 11:42 am Feb 25 2005
Country:
Location: Colorado

Post by Colorado Mike »

I agree that you have air in the system. a KDX can lock the front wheel just fine. In fact, it can do it as easily as it isn't to get air out of the system.

Try filling the thing through the bleed valve with horse syringe.
Mike

Life's tough, it's even tougher if you're stupid.
'04 KDX220
User avatar
strider80
Supporting Member III
Supporting Member III
Posts: 489
Joined: 12:26 pm Jul 21 2006
Country:
Location: Bothell, WA

Post by strider80 »

Has anyone installed a decent aftermarket braided line?
2005 KTM 250EXC
2000 KDX200 (gone)
AZRickD
Member
Posts: 524
Joined: 08:51 am Jun 29 2006
Country:

Post by AZRickD »

I installed the new rubbers to the master cylinder. I've pumped Dot3 down the brake line pumping from the master cylinder and up from the drain plug using a syringe. Some improvement, not much.

Mr. Wibbens suggested using teflon tape to seal the screw from leakage.

Rick
I done KX-ed QuailChaser's KDX220R
Bailey28
Member
Posts: 109
Joined: 10:19 pm Apr 17 2006
Country:
Location: Gainesville FL

Post by Bailey28 »

I have the same issue. When the bike was new, the front brake worked the best, I could lock it at will with one finger.

After several months, it felt spongy so I bled it. It felt a little better, but not like it did when it was new. the pads show hardly any wear. I changed the fluid again, and made sure the pads are sliding on the pin smoothly. I even polished the pin with steel wool.

The only thing I can think of that affected braking is when I wash my bike, I use Hondabrite. I try not to spray the caliper or disc directly, but some will get on there just by spraying the fender and forks, tire, etc.

I will try to break a glaze, if any exists by using a sandpaper on the disc before I buy new pads.
FAZ
AZRickD
Member
Posts: 524
Joined: 08:51 am Jun 29 2006
Country:

Post by AZRickD »

My problem isn't the rotor or pads, it's that the brake handle goes all the way with little pressure being developed. If I'm going down a steep hill, I have to use way too much rear brake, which doesn't work quite so well.

Rick
I done KX-ed QuailChaser's KDX220R
User avatar
KanuckKDX
Member
Posts: 166
Joined: 08:35 pm May 28 2005
Country:
Location: Alberta Canada eh

Post by KanuckKDX »

Man that's unsafe.

I would get someone else to repeat all your fixes - replace fluid, check for leaks, anyting else you can check. There is no way the lever should compress that far.

Dumb suggestion - have you adjusted the screw on the lever?
KanuckKDX
'01 YZ426F son's
'02 XR400 still for sale
'04 KTM 450exc it's all about the e-start
User avatar
kawagumby
Gold Member
Gold Member
Posts: 927
Joined: 10:09 am Nov 30 2006
Country:
Location: California

Post by kawagumby »

Sounds like air in the lines for sure. KDX brakes are equivalent to any bike out there.

You can bleed brakes by compressing the brake caliper with a lever such as a screwdriver shaft. Just lodge one end of the bar against the fork tube, pivot to push the caliper in. You'll see it move...then gently pump the brake lever (it will be soft) until the fluid refills the caliper and it gets hard. This gets rid of bubbles in the caliper itself.
I use this technique after hitting rocks while riding and getting air into the system - keeps the ride going and also can save unnecessary workshop hassle. It may work for you if the air problem is in the caliper itself.
1994 KDX200, Beta 200rr, yz125, yz250, kx100 modded for adult, gasgas contact 250.
User avatar
strider80
Supporting Member III
Supporting Member III
Posts: 489
Joined: 12:26 pm Jul 21 2006
Country:
Location: Bothell, WA

Post by strider80 »

Make sure the master cylinder is the highest point in the system so that air does not get trapped in the line and make sure the air has an uphill path the whole way. This can happen in the top bend of the line and possibly the bend near the caliper.
2005 KTM 250EXC
2000 KDX200 (gone)
IdahoCharley
Supporting Member II
Supporting Member II
Posts: 1005
Joined: 06:57 pm Mar 19 2005
Country:

Post by IdahoCharley »

What Strider said!! Also those that complain of weak brakes BUT have a hard lever should make sure they don't contaminate their brake pads and brake disc with either strong detergents or WD-40.
KTM 380EXC Mine
KDX 200 Mark's
TTR 125 L Wife's
KDX 200 Austin's
EC 300 Tyson's
WR430 Husky - mine
User avatar
Oldschool
Supporting Member III
Supporting Member III
Posts: 195
Joined: 05:02 pm Nov 07 2006
Country:

Post by Oldschool »

I didn't have a hard lever when I posted,after bleeding I did.

Tony
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

Typical 'bleeding' often does not work.

It is a far better method to use a pressurized setup.

Either a simple syringe (from the caliper UP to the MC), or get a pressure bleeder.

You should replace your brake fluid at least once a year. A MityVac makes the job simple.

Yes, you need to teflon tape the bleeder threads.

Re: 'it's that the brake handle goes all the way with little pressure being developed.'

You have a contaminated brake system. It needs fixin'. Bad! Now!!

After you fix it, if you still don't like it, get an oversize rotor.

Ski did that. Loved it. One finger control.

Most of my front braking is one finger already. Sometimes two. I guess I have REAL fingers!! :wink:

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
User avatar
strider80
Supporting Member III
Supporting Member III
Posts: 489
Joined: 12:26 pm Jul 21 2006
Country:
Location: Bothell, WA

Post by strider80 »

Hey Canyn, have you seen a pressure bleeder adapter for a dirt bike? I have a Motive pressure bleeder for my car. Maybe I should buy an extra MC resevoir cap and make an adapter.
2005 KTM 250EXC
2000 KDX200 (gone)
User avatar
Mr. Wibbens
KDXRider.net
KDXRider.net
Posts: 4884
Joined: 02:57 am Nov 07 2004
Country:
Location: Playing in the Poison Oak
Contact:

Post by Mr. Wibbens »

Mityvac type pump works GREAT

Mine's a knock-off, whatever brand Schucks sells, cost about $39

Quick an easy and be done with it so you can go riding!
Warning! This member tends to use sarcasm as a regular form of communication. If a post seems offensive, before you panic and fly off the handle, re-read the post and imagine it being said with a sideways grin.
((Bike Profile))
((Pics))
FIVE OUT OF FOUR PEOPLE DONUT UNDERSTAND FRACTIONS
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

The Mity-Vac is the ONLY way I could bleed mine... I tried all the other standard methods but they didn't work.
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
User avatar
Mr. Wibbens
KDXRider.net
KDXRider.net
Posts: 4884
Joined: 02:57 am Nov 07 2004
Country:
Location: Playing in the Poison Oak
Contact:

Post by Mr. Wibbens »

>|<>QBB<
Indawoods wrote:The Mity-Vac is the ONLY way I could bleed mine... I tried all the other standard methods but they didn't work.
Me TOO

Contaminated fluid has ruined a couple rides for me
Once up at Prospect, my front brake was dragging to the point where it would bog me down, I could only run first and second gear, anything higher and it would stall or lose traction. Turned out the fluid looked like root beer. Put in fresh fluid but had so much air in the system that it still did the same thing until I bought the vaccume pump

Another time on the Peak my front brake died on me, no pressure, and we had lots of gnarly downhill crap to do. I rode the back brake so much that it started to fade too. Downhills suck really bad with no brakes!
Warning! This member tends to use sarcasm as a regular form of communication. If a post seems offensive, before you panic and fly off the handle, re-read the post and imagine it being said with a sideways grin.
((Bike Profile))
((Pics))
FIVE OUT OF FOUR PEOPLE DONUT UNDERSTAND FRACTIONS
Post Reply