But i was prepared for that, i already ordered new pads some months ago so this evening i went to work to replace them.
What could have been a 15 minute job ended in a 3-4 hour session of misery.
First a picture of the situation:
You have take of the caliper by 2 bolts (14) , remove the lock-screws (12) and finally remove the 2 retainer bolts(13).
The bolts are 6mm plain steel rod with at the end an allen key head, the thread is on the allen-head and is 10mm -extra fine pitch(pitch=1.00 mm)
The 6 mm rod goes in the caliper in a tight fit 6 mm hole.
So that is a galvanized rod with tight fit in a aluminium hole: the recipe for corrosion misery.
I got one bolt out with no problem, the other was was stuck, heating it up,hammering,penetrating oil- it all didnt help, the allen recess became round.
So finally i drilled out the allen key bolt with a 6.5 mm (1/4 inch) drill for aprox 12 mm so head and rod became separated, then hammered out the rod and finally with a special screw-extractor removed the remaining allen head.
Of course i dont have a spare bolt so i made one just to get home out of a long 6 mm allen bolt+locknut
So to all owners with the 2 piston Nissin caliper; dont wait with removing these bolts until you have to replace the pads, do it next sunday.
Remove the two bolts, lubricate them with copper-grease and put them back.
In general this goes for all bolts which are threaded in aluminium parts; if you dont get them out while the bike is still new and lubricate them you will regret it later on...
I do all these "little" jobs at the company workshop i work where i have an outstanding equipped workshop, i know from experience that most motorcycle shops dont even have 10% the tools of what i have at my disposal.
If what i had to do had been done at a motorcycle workshop it would have cost me probably some 3-4 hours labor or a just simply a new caliper because they probably dont have the tools i used...
Another disappointment: i found quite severe corrosion pitting on the caliper pistons, this means i will have to replace these soon.
I really dont understand why it is that difficult to make a harmonica rubber which seals the complete piston off so no water/salt/dirt can accumulate on the piston, just like on car brake calipers...
The piston are now completely inwards so they wont leak but once the pads start wearing the pistons will come out and at some point the rust-pits will come across the seal and will start leaking brake fluid.
On screw extractor:
DONT use these: These are cheap,brittle and wrongly designed, the pitch is much to narrow so while screwing these in you will expand the broken stud, it will become even more stuck and you will break the extractor because they are usually made of cheap, very hard but also very brittle steel.
They WILL break and then you have the nice job off getting the broken and hard as glass extractor end out of your already broken bolt, believe me-i know from experience; these are crap.
These are already much better and if you can get them of a well know tool brand there is not much risk in using them, these will not break : The "thread" is not so fine so you wont expand the broken stud so much and you will have a good chance succeeding.
next post more...
)) tomorrow i'll add some pics
