RVF400 brake issues

[niteblade]

hi, i am a new RVF400 rider.

i realised that my front brakes would wobble badly during braking. i thought the problem was to do with my disc brakes being warped and true enough, my right disc brake was warped.

i got a new set and the problem went away. However recently, slight symptoms of the wobble have come back. i hope that that my new disc brake isnt starting to warp again

can anyone tell me where i should troubleshoot for the problem? brake callipers or brake pads? and what should i do?

and is it ok if i use my old left side disc brake on my right calliper because i really dont want to buy another new set again.

[silentRVF]

hey mate,
What are the new discs you put on?

I don't see how the calipers would cause this issue (unless they're not bolted on properly) and if the pads are worn to the discs I don't see them making the front end wobble. My guess is it's most likely to do with the discs.

And to answer your last question.. Not really. You should replace discs as a set, not individually. I wouldn't think about it unless it's the exact same brand disc off the same bike of the same thickness.

Maybe try the old left disc on the right side to see if it's the disc that's the problem and then go from there. The last thing you want to do is spend $400 on a new set of discs, only to find out that they weren't the problem in the first place!

Good luck with it.
Jonno

[force-v4]

Hello mate.

sounds to me like you may have a seized caliper or seized piston(s) - thats pretty easy to check for, it just means getting the caliper off & have a look & a little pump to check they're all moving or not.

With regard to discs, i swap discs around a lot to make up pairs with the same thickness & centres - as long as they're not arrowed for direction, you'll be fine but i do know that most genuine rvf discs are sided.

Also, you say you changed the discs, did you change the pads @ the same time???
Now this may cause debate but ive always gone with the rule of.......................

You can change pads with used discs but if you change the discs, you'll need new pads, as they'll need to bed in together.

This wont cause warping issues though, warping is caused by constant heat on the disc, usually caused by seized calipers - i cant see it being anything else.

[niteblade]

hey mate,
What are the new discs you put on?

I don't see how the calipers would cause this issue (unless they're not bolted on properly) and if the pads are worn to the discs I don't see them making the front end wobble. My guess is it's most likely to do with the discs.

And to answer your last question.. Not really. You should replace discs as a set, not individually. I wouldn't think about it unless it's the exact same brand disc off the same bike of the same thickness.

Maybe try the old left disc on the right side to see if it's the disc that's the problem and then go from there. The last thing you want to do is spend $400 on a new set of discs, only to find out that they weren't the problem in the first place!

Good luck with it.
Jonno

well, i replaced my old set of Disc brakes with another used but original RVF disc brake set awhile back. however the wobbling problem has come back again so i think that the problem isnt with the disc brakes...

[niteblade]

Hello mate.

sounds to me like you may have a seized caliper or seized piston(s) - thats pretty easy to check for, it just means getting the caliper off & have a look & a little pump to check they're all moving or not.

With regard to discs, i swap discs around a lot to make up pairs with the same thickness & centres - as long as they're not arrowed for direction, you'll be fine but i do know that most genuine rvf discs are sided.

Also, you say you changed the discs, did you change the pads @ the same time???
Now this may cause debate but ive always gone with the rule of.......................

You can change pads with used discs but if you change the discs, you'll need new pads, as they'll need to bed in together.

This wont cause warping issues though, warping is caused by constant heat on the disc, usually caused by seized calipers - i cant see it being anything else.

i didnt change my brake pads when i swapped the discs. i'll probably do a overhaul of my callipers and swap new brake pads in then.

is there any problem if i use left side geuine rvf disc brake on my right hand calliper? i know aesthetically they are different (the pattern of the dots.) but will there be performance issues?

[skinnydog0_0]

Hello mate.

sounds to me like you may have a seized caliper or seized piston(s) - thats pretty easy to check for, it just means getting the caliper off & have a look & a little pump to check they're all moving or not.

With regard to discs, i swap discs around a lot to make up pairs with the same thickness & centres - as long as they're not arrowed for direction, you'll be fine but i do know that most genuine rvf discs are sided.

Also, you say you changed the discs, did you change the pads @ the same time???
Now this may cause debate but ive always gone with the rule of.......................

You can change pads with used discs but if you change the discs, you'll need new pads, as they'll need to bed in together.

This wont cause warping issues though, warping is caused by constant heat on the disc, usually caused by seized calipers - i cant see it being anything else.

I agree i would always use new pads with new discs after suffering a problem with warped discs.
It might be worth checking your headstock bearings as this can cause a front end rumble under braking, and it is possible that the warped discs have damaged your headstock bearings?
Easy to check, just get the front wheel off the ground and turn the steering if there is any rougness or tight spots get them changed. Also at the same time push and pull the front wheel back and forward to check for play.

[niteblade]

my front bearings were pretty worn. so i replaced that.

did a mini overhaul of my calipers too. changed the o-rings and re-greased. also changed the brake pads.

everything seems to be working fine now.

only thing is that im using my old left disc brake on my right caliper (i have two warped right side disc brakes now i THINK, how to check for sure?)
can anyone verify whether this will cause any damage/performance issues? i dont mind if it doesnt look good.

[force-v4]

I would personally put the l/h disc on the r/h/s but some may disagree.
A disc is a disc @ the end of the day & as long as it fits & works, it'll get you by or @ least check out the problem a bit more - i really cant see it causing any damage or performance issues but there is a chance it could increase pad wear as the direction of the drill holes will be reversed.

I would really check the calipers first though, im sure this is where you'll find your problem.
If you go & fit another good disc on the problem side & there is a caliper issue, you can warp it in a matter of miles. I have personally done it a round trip of no more than 30 miles.

Good discs + seized calipers = bin material very quickly.

I also agree that you should now check the headstock bearing as well but im sure this wont cause the type of wobble you'll get from knackered discs.

The easiest way to check if it is a warped disc is to take off the front wheel keeping the discs on, get a pair of axel stands, put something through the wheel to support it on the axel stands & run it round, usually, a warped disc is pretty easy to spot, its just like checking for a buckled wheel.

Or alt, you can get the front end of the bike off the ground, remove the calipers & then run the wheel round.

I had a bad case of warped discs earlier this year, went through 3 second hand sets of discs in just the fitting time, 1 disc from each pair was bolloxed & none of the good 3 matched either centres or thickness - well pissed off.

You can have discs machined true again but its not cheap & you loose the thickness in the "repaired" area.

[force-v4]

Ok cool, you've banged another post in the while i was typing away.

see the above but im sure you'll be ok now.

[Drunkn Munky]

only thing is that im using my old left disc brake on my right caliper (i have two warped right side disc brakes now i THINK, how to check for sure?)
can anyone verify whether this will cause any damage/performance issues? i dont mind if it doesnt look good.

Now your calipers are unseized and working fine put the new (maybe warped) disc back on and see what its like, if it wobbles then its fooked.

Im pretty sure a disc particually a new one can be straightened, google maidstone motoliner. They can straighten pretty much anything.