PDA

View Full Version : Right, the fun and games continue aparently!



Hunar
10-11-10, 04:19 PM
With both my bikes off the road due to briefly meeting a diesel spill on one, and the fairly recently fitted exhaust falling off the other, a good friend of mine came to my rescue and lent me their SV650, very decent of them I thought. However the current cloud of bad luck had not fully rained itself dry!

I had an interview to do on Monday for my radio show, and needed to borrow a Microphone to do the interview with, another good friend came to my rescue and offered me theirs, I just had to come and get it, SWEET!

So off I go on my friends SV650 from Swindon to Thatcham, no worries, M4 was clear and fecking cold! Pushed the bike onto my friends driveway, went inside for a cup of tea and some rather nice biscuits!

When I left, it was pointed out I had a nail in the rear tyre, which thankfully turned out not to be a nail at all, but a much sharper shard of metal instead. This had made a nice hole in the tyre BETWEEN the tread, but had not actually punctured it. Right take it nice and easy on the way home, and get that checked out the next day, no problems!

Yeah, I know, I spoke too soon there, as I came to wheel the bike back out of the garden it quickly became apparent that one or maybe both of the front brakes had seized on, so after some discussions with the AA and a call to the bikes owner that I really didn't want to make, taking into consideration my recent bad luck with my bikes, I manage to get the bike back to my place, on a low loader, and wouldn't you know it, the brakes had unsiezed on the truck, probably due to the movement, so easily pushed the bike into it's parking space.

The next day I go out for my morning smoke and decide to see how the brakes feel today, alas the unsiezing of the night before had been replaced with the resiezing in the morning, not that I can complain about that, it was a cold morning and to be honest parts of me felt like they had seized up also, so I could forgive the bike for that much at least!

This morning the weather is quite mild, and no real wind adding to the chill factor, result! I can go and check these brakes out. Now I'm not a skilled mechanic, so I take a bit of time to look for info on the web about how to deal with this problem, and found a handy little 'how to' on a SV650 forum, sweet! Simple enough and easy to follow! The right hand calliper, no worries, came off a treat, cleaned up nice, pads back in and back on the bike no problems!

Yeah spoke to soon again! left hand calliper, a bit harder to get off the disc, so I'm guessing it's probably only the left calliper that's locking the wheel, but it comes of, run through the same procedure as the other calliper, more crap on this one and not as easy to clean, but the pistons are free and can be compressed back fairly easily, refit calliper, and start to gently pump the brake.

Yup you've probably guessed the outcome...........................................

The fecking fuel tank explodes!!!!!!!!!!

No it didn't really, what really happened as you have probably guessed, is the left calliper just relocked back onto the disc!

I'm wondering if I should just take both the callipers off and get them professionally cleaned, and then refit them, I'm guessing I would need some new seals for this. I'm not sure how difficult a job this is to strip and rebuild callipers, never done it before, and as this is a friend’s bike, I would like to make sure it is done properly before I return it to them.

Also if it is required that the callipers come off for a good clean and refitting, I am guessing it would also make sense to upgrade the rubber hoses for braided ones at the same time?

silly_simon
10-11-10, 04:39 PM
"Also if it is required that the callipers come off for a good clean and refitting, I am guessing it would also make sense to upgrade the rubber hoses for braided ones at the same time? "



If it was me mate then yes, I would replace the hoses. After all it wouldnt make em any worse ;)

If the calipers are stripped then yes new seals will be needed and to be honest it would be false economy to rebuild them without doing the seals too [smiley=thumbsup.gif]

I have never done a caliper strip YET so unfortunately cant help with this :(

Bornagain
10-11-10, 04:51 PM
Bad news dude
But on a lighter note, i'm looking forward to see what you ride in on Friday ;D ;D

When i have a biking issue i normally give col (greenman) a pm, usually does the trick [smiley=thumbsup.gif] [smiley=thumbsup.gif]

Thorkill_The_Tall
10-11-10, 08:25 PM
Overhauling brake calipers should be a very straight forward task.
The problem is that, suprisingly, brakes are one of the most neglected parts of many bikes. If little or no basic care has been given to them, you could be in for one mother of a job.
Even Japan's finest seem unable to cope with a British winter.

Worst case scenario could be:
Bleed nipples siezed/rounded off.
Mounting bolts siezed/rounded off.
Pistons have become as one with the caliper.
Pad pins seized.

If you are lucky and the pistons come out just with the pressure of the fluid and you have all the parts are to hand, you should be able to do it in no more than an hour.
If any of the above occur, you could be looking at half a day, minumum.

Top Tips:
Get some brake cleaner from a motor factors.
The quickest way to remove stubborn pistons is to use compressed air.
Remember, DOT 4 is not compatible with DOT 5.
Dot 5 is not compatible with DOT 5.1.
Grease the new seals with silcone grease, not ordinary grease or Coppaslip.
If the front brake is a bugger to bleed, take the master cylinder off the bars and hold it as high/straight as possible.
Buy a new stainless steel bleed nipple.
Most manufacturers recommend changing original rubber lines at between 5 or 7 years. Replace with quality stainless braided.
Wear a pair of those pervy latex gloves ;)

Hunar
12-11-10, 02:12 PM
Brakes win!

2 hours later and one piston is freely moving the other decided that it was going to start to move then lock in place and that's it!

I'm not confident in taking the calipers apart and stripping them, I really don't think my mechanical skills are up to it, and I am more likely to do more harm than good if I do. It's a friends bike, so I don't really want to practice on their brakes, and I don't want to do more damage, so I think the best course of action is probably to take both calipers off and take them to a garage for cleaning and refitting of seals etc.

So anyone know any good places in Swindon? I don't have any transport at the moment so it will need to be in Swindon ;D

jonnydangerous
12-11-10, 02:42 PM
gissa shout fella, get them to "JD's engine tuning shack2 hes a bit of a god, or so ive heard, and he works for kebabs (or kebab AND chips if you already owe him food)...hahaha

youll need caliper seal kits (2 seals per piston,pattern parts are ok)....

we can fix anything fella.......

PM sent.

Jacde
12-11-10, 04:00 PM
Hunar / Jaydee
I'm free on Sunday if you need a lift to Jaydee or I can collect breaks and drop em off to you?
[smiley=thumbsup.gif]

Snowy
12-11-10, 05:22 PM
Or, if you can give the brakes/seals to someone going on Sunday's rideout I can get them to JD next week.

jonneyflame
12-11-10, 05:44 PM
maca had the same issue on her sv turned out to be be the seals, cost around £12 and was an easy DIY fix

SupeRDel
12-11-10, 06:46 PM
Nowt complicated about disc brake systems.

Basically its a pump on the handlebars. You pull the lever which pressures the system and pushes the pads onto the disc.

Release the lever and the oil flows back releasing the pressure.

The brakes on my RD400 are over 30 years old and all original besides the oil.

My brakes were beginning to sieze after I bought it. Basically with the age the tiny pressure relief hole in the master cylinder was blocked with crud.
You apply the brake while riding and when you release the oil cannot return to the master cylinder so the pads keep a bit of pressure on the disc.
As the pads keep rubbing it generates heat in the system and the disc. As it expands with the heat the brakes bind harder till you come to a stop.
Let the brakes cool down fully and away you go again - till you touch those brakes again... :-/

Best way to remove pistons is too use the bikes own master cylinder to push them out. Its wot it built to do!
Compressed air can be highly dangerous and can damage the parts.

A gentle way to remove pistons is to connect a grease nipple to the caliper and pump them out with a grease gun.

Bit slow and a bit messy but you are gonna clean it all anyway and the pistons come out with no violence.

Rebuilt mine with original old seals after a clean. Works fine.

Brake test - if they are working absolutely correctly you should be able to spin the wheel freely.
Apply brake - wheel locks.
Release brake - wheel should now spin again

Hunar
12-11-10, 07:41 PM
thanks for offering to help with delivery guys, but have only just ordered the seals so will not have them in time. Not sure when they will arrive, but wemoto are usually good and the site says the parts are in stock so with a bit of luck should only be a few days, which knowing my luck at the moment will end up being months lol

jonneyflame
13-11-10, 10:15 AM
I'm in Swindon next weekend, so if you need a hand fitting them give me a shout. i think i still have two seals from the set that i ordered (lazy i know but will fit them if the other side locks up). so if yours havent turned up by the weekend then i could bring mine, just let me know

Cemorah
16-11-10, 08:52 PM
Hunar I live in Cricklade if you can make it there I'll be happy to help Done a few in my time nothing too scarey PM me if you want help.