Judder under braking an stuff (RS125)

[paulthewitt]

ok, this is worrying me. occasionally when i brake the bike judders, and it judders violently.

also there seems to be a clicking noise coming from the bike...from infront of me (so the wheel, to the dash area) that is linked to how fast i am going...the clicking speeds up as i do and slows down as i do.

bike is an rs125...and i cant afford to get abigger bike before someone suggests it!!!


i think these two maybe linked. as they started about the same time. i have checked the pads and caliper and that seems fine. thewheel bearings seem fine, as do the head bearings, and the speedo cable (havent checked the speedo drive but it is working fine so cant see how itt is that)

if anyone has any ideas...tell me please.

Thankyou
paul

[badlydamaged]

Maybe a warped disc, does the front brake lever pulsate when you put in on at all? Other than that, I dunno what it might be.
____________________
My bike: 1988 Kawasaki KH100 Status: Polluting Devon with two stroke smog and noise pollution!
"Its not your engine size that matters!, It's what you do with it that counts"
Add me to MSN if you want! [email protected].

[Kickstart]

Hi

Most likely cause of judder is a warped front brake disk. It would be made far more noticeable by worn steering head bearings (and it can be difficult to spot movement in them).

Check the disk carefully. Check all the mounting bolts are in position.

Also check the speedo drive.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[paulthewitt]

The judder has come on very suddenly, and doesnt happen all the time.

thats why i am so confused!!!!

any other suggestions. i cant see any warpin g in the disc!!

thanx,
paul

[Kickstart]

Hi

One possible problem could be oil on the disk, but I would expect this to also result in useless brakes, and only really cause a judder at low speed.

Also double check your wheel bearings.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[paulthewitt]

ok.

this is intermittent....sometimes it happens sometimes it doesnt.

could it be down to new break pads. i bought some EBC pads from craig at cmp, and they dont seem to stay against the pistons lof the calpers but come together and are lose when i take the caliper off. they seem to be fitted correctly as i had no prblems with my old pads....which i removed and fitted the same way.

out of interest why would oil on the disc cause judder??

thankyou for help
paul

[priller]

Clicking is probably the speedo drive.

I've got ebc hh pads and havn't got a problem, I take it you renembered to refit the metal bit that goes under the pin?

[paulthewitt]

yup i did.

also now seems to be a squeeking noise that is coming from the front!!!!

i believe the clicking noise is the pads moving. see previous post. they wont stay flush to the pistons!!!

paul

[Kickstart]

Hi

I have EBC HH pads in my RS125. Not had a problem with them.

I have seen pads clicking around in the caliper from a slightly warped front disk.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[spikus1969]

what year is the RS because i know on the 90-94 on the ebc pads they supply a shim that fits on the back and sometimes this causes the clicking sound,also take a look at the bobbins on your discs are they started to work loose that also causes aclicking sound,
it does sound as though you are going to need a disc,
are you racing the RS125 if so might be able to help on the disc front
____________________
Your online store for all EBC Brake Pads,
Rotors and Clutches
www.brakes4u.co.uk

[paulthewitt]

looks like i need a new disc then!!!!

this bike eats money. a love affair is turning into hatred!!!
spikus, the only racing i do is on the road when its quiet.....and i am no rossi!!!

how could you help with the disc??? i need all the help i can get.
also the bike is a 98 plate. thanks to all who have helped so far.
paul

[Kickstart]

Hi

Send Craig a PM ( https://www.bikechatforums.com/profile.php?mode=viewprofile&u=1388 ) as he runs a business on the side doing parts for the RS125 and the like. He should be able to do you a pretty good deal on a disk.

First though give the disk a careful check. Ensure that the mounting bolts are secure. Also get someone to hold the front wheel off the ground. Then spin the wheel and see if you can see the disk wobbling (hold a screw driver just off the disk which should make it easier to spot any movement).

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing