Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

Oil leaked onto brakes/pads/disk/wheel

Discussion in 'Technical and Troubleshooting Torque' started by AndyJ, Sep 22, 2008.

  1. Lately I've been fed up with my bike's poor brakes, until I rode my friend's vtr250 and realised that the other bike's brakes outperformed mine!

    Investigating mine we found oil on the disk, and now on closer inspection I realise the oil is everywhere, on the pads, disk, in the wheel hub, caliper etc.

    q: should oil or grease come from the wheel hub?

    I'm going to clean out all the parts on the front end tomorrow, does anyone know what solvents I should use to clean the oil out?

    q: is it possible for the brake pads to have been soaked by all this oil beyond safe use, or should I have a go at cleaning them out?

    Hopefully last minute braking at the red lights will now be safer :oops:

  2. I used to use a mixture of thinners/petrol or kero depending on the gunk factor but in your case if it's only a few smaller parts pop into an auto-parts store and get plain jane degreaser. Grab a large qty of distilled water for rinsing off afterwards, wouldn't want brake components exposed to foreign matter in tap water.

    Brake pads are made of a combination of materials (a recipe if you like) and part of those materials used is to deal with heat. Anything foreign that seeps into the pad is therefore going to upset the way the pad performs, and in the case of heat your talking about oil and grease which are fantastic at holding on to heat. Every set of brakes i've ever seen that have been affected by a foreign matter were instantly binned by the mechanic working on them, the rationale' being "why take the chance for a few $$$ ..... it's brakes"
  3. yep. time for new pads. not a brake fluid leak is it ?. oil on your brakes would be a biatch for sure.
  4. Probably got a leaking fork seal, and also probably got a near empty fork as well given it's taken you so long to make the trip down to the front of your bike and actually look. :shock: The handling should be at least a good match the braking performance, if that's any consolation.

    A can of brake cleaner is a winner, but replace the pads.
  5. that was my next thought.
  6. update:
    I've cleaned the disk, pads and wheel.

    There was oil coming from the inner wheel (bearings?), so I cleaned that out
    with just some paper towel.

    Next the pads, I had a go cleaning them with the mixture posted above (as best i could), then rubbed them on concrete to mechanically clean the surface, repeated this once more and rinsed with boiled water. They look ok, I'll give them a go later and throw out if neccessary.

    Disk has been scrubbed clean with a toothbrush.

    I'm holding off cleaning the calliper until I've got the right solvents.

    Now, just found what might be the source of all the oil. On inspecting the speedo gear, mounted to the left hand side of the wheel hub, I found if was FULL of a greasy sludge. Some grease is obviously needed for this moving component, but could this grease pour out of the seals and all over the front wheel? Or could a seal leaking from damage etc.?
  7. Before you try to conceive how the small amount of grease that is in the hub and/or speedo drive can defy gravity and get up on the caliper, how about you check your fork seals and brake fluid level as suggested by others.

    Each fork can have as much as 300 or 400ml of oil. The brake system will have at 50ml of fluid, but by the time you lose it you have no brakes. The speedo drive will have less than half a teaspoon of GREASE not oil, same with bearings. The only sources for so much fluid as to coat everything are:

    1) Brake fluid leaking from somewhere - either the piston seal, the caliper or a joint - resulting in extremely poor braking.

    or more likely:

    2) Fork oil from leaking fork seal, coating brakes and resulting in extremely poor braking. If your fork seal on the caliper side is wet with oil, you've probably found the problem. Often this side leaks first because the fork bushes on that side are subject to more load when brakes are applied. When they flog out to the point that there is play in the leg, the seal follows suit.

    Not wanting to sound nasty, but you need to know when you don't know enough when it comes to ensuring your bike will stop. It's not stuff to muck about with. Brakes are what come between you and a world of pain.
  8. I've cleaned the forks, and will look for a leak, though it seems unlikely as the forks were serviced about 9 months back.

    As for checking the brake fluid, I think I'll have to get a mechanic to check, as I don't have the tools to flush the brakes.
  9. VTR

    If you're near Ashburton pop in & I'll have a look at it. Use a proper brake cleaner product as it won't leave a residue. Throw away the pads & buy new ones as once contaminated with oil they'll never work properly again. Duncan
  10. Maybe someone over oiled the speedo cable and this is what's leaking out. But judging by the amount of oil you appear to be talking about, I'd say check the forks for leaks.

    You can check the brake fluid yourself, you dont need a mechanic. There should be a small sight window on the master cylinder, or alternatively, the master cylinder may be made of opaque plastic and you can see the fluid level throught it. If not, just unscrew the cap, remove the seal and have a look... :)
  11. I've cleaned the whole front end, each individual part, and put back together.
    Checked the brake fluid, it's full to the top -> not the cause

    Went for a 150km ride today up to sky high and back, looked for any oil/grease on fork stanchion tube, it's all clean. Disks are now clean too :)

    Brakes aren't 100%, but will give it another 200kms or so in case the pads need to wear in again. (i'd bin them, just too skint for new ones at the minute)
  12. Good to hear all is well.
    Make a habit to check your bike at least 'weekly'. It's not much good finding out your brakes don't stop ya seconds before you are about to do a rear-end :shock:
    If your brakes still feel a little fague mate, replace the pads. They may be contaminated. Oh and "brakeKleen" is a great lil product for removing oils etc from brake components.
  13. Remember also that oil leaks stop when there is nothing left to leak...[/code]
  14. good point.
    I'd have a look at the oil fluid level, but since having my forks converted for cartridge forks I don't know how to open up the cap and check the fluid. It's got vtr1000f top caps.
  15. If the bike is second hand, some numpty may have decided to oil the speedo gear instead of greasing it, or used a cable oiler without consideration for the excess. consider re-greasing the speedo gear next service
  16. Slightly offtopic; I was wondering why you considered the VTR250's brakes to be subpar in that VTR250F thread, as I considered them to be pretty good for a bike without braided lines.
    I guess this might explain your thoughts.

    Recently my mountainbike's disc brakes got contaminated by chain lubricant. Replaced the pads and cleaned the discs thoroughly with brake cleaner, then found a big steep hill to burn the remaining contaminants off - Difficult to generate enough heat to burn off the contaminants, car-style, when you and your bike only weigh 100kg.
  17. I still stand by the comment I made. This is the second vtr I've bought, I learned on one about 4 years ago also.
    They've never given me stopping confidence. Or maybe it's just that I've always had the standard pads and should try a sintered material?

    That said I've tried a cbr250 with dual disk front brakes, and they were less effective still.
  18. I did cleaned out the speedo gear and added a touch of grease only.
  19. One interesting point.

    My friend's vtr has a different brake master cylinder reservoir and cap.
    Hers: English instructions on cap, no writing on res.

    Mine: Japanese characters on cap, "clean filler cap..." sticker on res.

    Could the first one (the one that seems to work better), be a different master cyl., from a Hornet cb600f perhaps?
  20. you'd need an indepth parts catalogue to know, eg micro-fisch film from that era that states manufac for year model, or manufac's data sheets on said master cyls.

    Sure they could be different internally, I can only speak from years of experience in car parts where a PBR master cyl assy was different to a Nippon but depending on the month (not the year) the car was manufac'd you'd be hard pressed to know what model had which without that catalogue.

    Not meaning to be nasty, but you're mind-effing yourself on braking issues whilst still running around with dodgey pads. There are numerous things besides master cyl's alone which affect brake performance ..... such as internal valve diameters, caliper slides and piston sizes, line size and distortion rates, heat retention, disc thickness blah blah blah. Some subtle some not but if you're serious about nutting the issue out then go to a motorcycle mechanic who specialises in your bike, save some cash and buy his advice or expertise. Buy some pads first though yeah ?