help! nut head's rounded off

Got my MOT on Wednesday so I set about finishing off 2 last jobs today - swapped the exhaust for the standard can, changed one set of front brake pads, got to the 2nd and the pin that holds the pads in has previously been treated badly - the head is rounded off. the pin I mean is arrowed (badly!) in the pic below. Now I dunno what to do - can't get the pin out so can't change the pads, and they're on the wear indicator so easily an MOT failure :( amny ideas guys, or is it new calliper time?

http://www.jameseades.co.uk/misc/callipers.jpg

Looks like an allen bolt in the pic. If it is, put the caliper in a vice and try wacking in an oversized star bit into the round off part. If you're lucky this should take and you can undo the bolt with vice grips or similar. New bolt/bit is cheaper than new caliper.

had a similair sort of problem it too was sorted out with an over sized star bit, and plenty on WD 40 the night before, use plenty of cooper grease on the new ones, you'll thank yourself for it in the long run.

cool thanks guys, will try that tomorrow. any tips on how to take the calliper off? do i need to drain the brake fluid 1st or anything?

if you are going to take the caliper off then its best to release the brake fluid, from the bottom banjo nut, and allow it to drain in to an old coffe jar,
once the brake line is removed you should just have to undo the caliper bolts,
may be worth giving all the pistons a really good dig out and all pins and BACK of the new pads a coating of cooper grease, but make sure none getts on the front of the pads of discs.
then once its back on bleed the system , it might be worth while doing the other side as well so you have fresh brake fluid on both sides, if you need to know how to bleed the system then let me know and i'll be able to talk you thro it

cool thanks mate - I'm a complete novice when it comes to bike maintenance! was impressed that I read up on how to change my pads, and then annoyed when I got stuck at the 1st hurdle :(

i can take some pics as well as talk you thru bleeding the brakes just let me know

that'd be great, thanks :D where can I buy more brake fluid over the bank holiday weekend then? MOT is wednesday lol - think I may have to cancel it until I get this all sorted :(

You could try a local Halfords Dabz for the brake fluid (they're open sundays)- just make sure you get the right type for your bike i.e DOT4. Should tell you in the manual or may be printed on the fluid reservoir on the handlebar.

If you havn't got ABS you can bleed the brakes easy enough but will help if you have some plastic tubing to go over the bleed nipple and into a jar of brake fluid. Halfords will sell one so buy one at the same time as the fluid.

Bewarned - Brake fluid will strip your paint off in seconds. Keep plenty of clean rags handy and if you do get some on the paintwork have some warm soapy water already prepared and get it off quick!

ok here we go this can be used to bleed the brakes, replace the brake fluid, or when you are changing the brake lines over to braided hoses.
the secret to success is preperation..
the night before clean well evry thing that you are going to touch with warm saopy water, and dry properly, then soak all nots banjos bleed nipples with WD40 or GT85 (it smells better)
ensure you have the correct fitting tools length of pipe that fits, and an old container.
that morning dry off any WD40 otherwise tools might slip.
then draw out as much fluid from the res as possible an old turkey baster is good.
if the line are to be replaced orthe caliper has been removed, then crack all nuts banjos off and bleed nipples,
then do up so no fluid leeks.
then fill the res up with the correct brake fluid, i use Putoline full synthetic brake fluid DOT 4.
Have plenty of clean rags to protect the paint work and som ewarm soapy water to clean up any spills.
crack the banjo on the master cylinder, squeeze the brake lever then do up , repeat this til no air is coming out of the banjo, once happy tighten up.
http://i163.photobucket.com/albums/t...d/100_0719.jpg
then move onto the brake caliper nearset the brake master cylinder, and losen off the banjo squeeze the brake lever then tighten up the banjo, and relaese the lever, continue to do this til no air is coming out of the system, constantly check the res and top up with fresh brake fluid never let it run dry otherwise all this wil have to be repeated.

http://i163.photobucket.com/albums/t...d/100_0722.jpg
once you are happy that no air is coming from the system then tighten up and repeat on the otherside
then move on to bleeding the calipers, loosen off the bleed nipples, on th ecaliper nearest the brake master cylinder, and place a length of hose over the bleed nipple, then squeeze the brake lever, then tighten up the bleed nipple and release continue to do this til no air is coming from the bleed nipple, tighten up, and repeat on the other side
http://i163.photobucket.com/albums/t...d/100_0725.jpg
Onc ehappy no air is in the system by checking the brake lever feel and travel top up th eres and fully tighten all bajos nuts and nipples, use a torque wrench to the correct setting.
http://i163.photobucket.com/albums/t...100_0723-1.jpg
fully clean all areas and tie back the brake lever with a few cable ties to check for any leaks.
http://i163.photobucket.com/albums/t...d/cabletie.jpg
i hope that this is of use any problems let me know
fred

if u r not sure wot u r doing for your own safety dont play with the brakes!! r u based in swindon? if u have not taken the brakes off yet u should try to get the pin out first as if u can it will save a lot of hassle .if u r in swindon let me know and u could come round to my place and we can have a look it might not b as bad as u think.i have delt with this on road bikes and x,ers.

I'm not in swindon, the bike's in Trowbridge, and no MOT after tomorrow so gonna make things a bit difficult! My current thinking is I might be able to order a replacement pin and drill this one out - does that sound sensible?

really should try the over sized star bit first, as drilling out can be a pain, and you will need an extractor kit as well

If the above doesn't work then the best way would be to split the caliper into two half by un-doing the bolts....you'll find that pin only screws into the side where the rounded head is....clamp that half in the vice using the two bracket mounts....then get a pair of molgrips on the pin sticking out at this point to unscrew it.

yes get a new pin try the over size star driver ,you may also b able to grip the pin in the middle between the pads with a fine point mole grip .u can also try to gentley warm the calipar around the pin with ether a rag soked in boilling warter or a hot air gun.i would soke over night in wd40 tap in star drive clamp on grips then heat u can then pull on stare drive and grips at same time giveing 2times the force.if u do try spliting the caliper check if any seal r avlb as most r not.

Grinding paste used to seat valves can also be used to give a littele extra grip, on the head as well

How did you get on with the caliper

not well lol, hammered a flat bladed screwdriver well into it, as soon as I put any pressure on it the bolt just came away. Gonna call in the expert help of Terry at D&H motorcycles in bath who's gonna help me bleed the brakes, take the calliper off, then he'll heat it all up and get the bolt up, then help me fit the pads and then MOT it :D

Well i hope it all goes well and gets it sorted soon

yeh me too, would've loved to have been out and about tonight :(

Well, without being too personal mate..... how are your nuts now!?!?! :-[

all booked in for MOT and sorting out on May 30th...stuck on 4 wheels till then hehe