marcus_136

Hey!

Having this annoying problem.

When I am braking in lower speeds (for example if I should do a burnout) the front end is shaking like hell. I even ended up dropping my exhaust .

I have changed steering beerings and tightened it up, changed the oil, the seals and the bushings in the fork and checked if everything is ok.

I have also changed the front brake pads without any results.

Anyone got any good ideas to help me out? I think if the rotors where messed up, I would loose pressure in the front brake master, but I dont do it. And I dont have any shaking problems when I am in a faster speed...


/Marcus

Yamaha412

hmm, without riding it i would most likely say that its your triple tree adjustment, there is a torque spec on them when tightening the nut on your triple clamp. to lose will cause head shake and too tight will wear bearings alot faster. try this so that you can definatley count out that as the problem...

hoist the front end up, grab your forks and push and pull (front to back) there should be a tiny bit of play when doing this i'd say 1/2 inch at most. and if thats good then im not sure, maybe a wheel spacer is crooked or somthing which causes the front end to shake like hell due to all the pressure being put on it when doing a slow burnout.

good luck let me know what your find out

skillz

could be guides n bushings in your forks.

BVRider1

post up what you find out. I have the same issue

marcus_136

I dont think its the bushings or anything in the fork cause I have already changed that and it didnt solve the problem. ANd I have changed the steeringbearings so I dont think thats the problem either.

I noticed that my brake pads have some play in the calipers and that the calipers are a little damaged where the brake pads is fitting in. Could that cause this problem maybe?

sdfkillz

i dont know where you got the idea that there should be any play in your front end but you would be wrong. if your forks move in any other direction than the up and down motion of the fork slides or the left and right turning of steering something is wrong.

skillz

what front end are you using

marcus_136

Stock 05 636 frontend.

crashtest 750

Warped rotors. If they are slightly warped you will not feel it on higher speeds. You won't feel it in the master either.

marcus_136

Ill order some new ones and see if that helps. Thanks!

BVRider1

fixed now?

02gsxxr

that doesnt make sense..... Now i'm a auto mechanic and you dont feel warped rotors at low speed you will def feel warped rotors at high speeds with the slightest pressure from the brakes.... so i would assume that goes the same for a bike....

PETe P

my budy has the same problem. but it's the actual fork hoping as if he were hitting whoops. i was thinking it might be the dampening and compression all jacked up?

BVRider1

My f4i has been doing this all season and I'm about to toss the forks out, but I am interested to see how people are fixing these.

I have done:

new rotors, fork seals, bushing, brake lines, and calipers.....

My next step is steering bearings and that's really all I have left....


hopefully that fixes it, if not maybe the dampening and compression is just fuct....

old man roger

i have a thought well really a guess but it should be very easy to test , forks have an air chamber at the top of the fork when the bike has both wheels on the ground but when you do a wheelie the fork oil will flow to the top of the fork making the air go to the bottom..

now im wondering if that is making the compression and rebound not work like it should because of air , any one interested in testing this can simply ride their bike around on two wheels for a few minutes braking occasionally working the forks up and down to get all the air worked out of the system and then try doing burnouts...

like i said just a guess

old man roger

oh and my other suggestion is to get the back tire spinning faster , it puts less stress on the forks

PETe P

never thought about that. i've been out of the mx game forever but they used to have things to "burp" the chambers wonder if that would do the same thing you are describing.

old man roger

not really, the air chamber in sport bike forks are there on purpose and they need to be there ..

some old dirt bike forks needed to be burped because they get hot and build pressure

BVRider1

good point of view OMR...

old man roger

might not be the problem but it's so easy to test i figure it's worth a try