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Today I was just finishing off the remaining items of my service.

• * Cleaned ad greased the clutch lever pivot
  * Cleaned and greased rider and pillion footrest pivots (and even found each of the pillion footrest ball-bearings that I dropped)
  * Greased the pillion seat catch
  * Did my annual clean of the brake rotor bobbins
  * Adjusted the chain
  * Sorted out the fuel filler water drain that wasn't draining properly
  
  Then when it looked as though the showers might be finally over I set about the hydraulics.
  * Fitted the new clutch master cylinder banjo bolt with a bleed nipple
  * Changed the clutch fluid and bled the clutch (that new bleed nipple makes a huge difference)
  * Changed the front brake fluid - using the right calliper bleed nipple.
  
  Then the fun came ......
  
  * Tried to flush through the new fluid to the front left calliper .... damn that nipple is tight ..... bit of easing fluid on it and wait a bit ..... try again ..... no luck ... bit more easing fluid .... put the ring-end of my best spanner set on the bleed nipple and give a good tap with a hammer (to give a bit of shock) .... nope .... heave on the spanner .... and it spins on the hexagon which has now become a new geometric shape with rounded corners.
  Bugger.
  Mole grips wouldn't budge it.
  
  * So I gave up and did the rear brake (again the nipple was hard to move but I managed to sort it without damage .... guess the slightly bigger hexagon on the rear may have helped.

So, eventually I'm going to have to sort this one out.
Obviously I'm going to have to replace the bleed nipple
Anyone got any tips on how remove the old one with the minimum of fuss / risk of damage.

Where possible the application of heat is always fav on seized parts.

Samray wrote:Where possible the application of heat is always fav on seized parts.

Cheers Sam - I'll ride with the brakes on for a while

With a bit of air in there it should boil.

Hi Andy, I'd second what Sam says. If you're serious about this, the caliper will need to be removed from the bike, and preferably have all pistons and seals removed. Then get someone with a gas axe to get mediaeval on its ass. It probably wouldn't hurt to give it a soak with Plus-Gas, but heat (real, proper heat) is the key. Scotch Bonnet Chilli levels of heat...

And then the old bleed nipple should be replaced with a stainless one, of course...

Yeah .... I was thinking this will probably be a calliper-off job .... was hoping someone might have some magic voodoo that would avoid it.

It can wait now until I decide to fit some braided hoses as I'll have to drain it all down for that.

The other option when I've got the calliper off is to drill it out - it does have the advantage of a good pilot hole.

I'd probably be tempted to try to weld a nut on it, which would also warm things up nicely.

Samray wrote:I'd probably be tempted to try to weld a nut on it, which would also warm things up nicely.

Yeah that could be a very good idea

All of these good ideas are much appreciated and a plan of action is being formulated for when I get round to this.
Cheers everyone.

.... and if there are more ideas, keep them coming

have you tried using a/f single hex socket probly next size down and gently tapping it on

rov8 wrote:have you tried using a/f single hex socket probly next size down and gently tapping it on

I'll have to have a look - not sure if I've any imperial sockets that are that small ... but I'll dig through my various toolboxes to find out

Cheers

hex socket as rov8 ses and tap it on andy.giveing these monkey metal nipples heat will shear them every time.either way i think your going to have to get your drill out. soz.

The problem with heat and calipers is that the fluid draws the heat away, heat also damages the nice gold paint. You have two options as far as i can see. If the brakes are bled up ok with no spongyness and if you can bleed the other caliper so most of the fluid can be changed, dont worry about it, fluid is only changed cos it attracts water, oil floats on oil and therefore finds its way downhill to the caliper and when the water in it boils at 100C, it turns to compresable steam which gives a spongy brake.

The only proper engineered fix is to take the caliper off use plus gas and a heat gun......gently, remember these are used to strip paint! use a hammered on A/F or BA socket. Try also a very small pair of stilsons, the kind that grip more as you tighten them. When undoing rusty nuts its sometimes a good idea to tighten the bolt slightly it just "cracks" the corrosion, but its risky as somemtimes they shear, remember the nipple is hollow so wont take much torque befor it wrings off.

If it Wrings off you can then only drill it or spark erode it, both of which are best trusted to your local eng workshop, do you have a tool room at DENSO? If so for a drink I`m sure they would help.

Finally when done use COPASLIP on the threads and just nip up the nipple with a small ring spanner, it doesnt need to be tight, it will never happen again

Good luck.

Of course, you could always ditch the calipers and replace with some blingy ones

Yes I am adopting the "don't worry about it" approach for the moment though I know I will have to sort it out eventually .... and it is fairly clear that when I do, it will have to come off the bike.

When it does, with the banjo removed, there is much better access to the nipple - so I'm hopeful that one of the methods will work without too much grief - though avoiding the nipple from shearing might be an issue,

Drilling is a last resort as I'll have to strip the calliper completely to make sure there is no swarf in there .... but if needs must I can do it - at least it has a good pilot hole!

I can probably get some stilsons on it then or a tight fitting socket or a nut welded on .... then with a bath in easing fluid (that's the nipple - not me) and a bit of heat .... maybe it'll shift.


Copper grease is (as always) at the ready

Cheers

wavey wrote:Of course, you could always ditch the calipers and replace with some blingy ones

Also being considered ... and then can restore the originals at my leisure to either keep as spares or sell to help finance the deal.

Already have my eye on some ......