View Full Version : Brake power. (or not).
I have been trying to sort out the front bakes on my SV650 (K4). The weren't particulary powerfully and the pads looked a bit glazed so I have:
Fitted new EBC pads
Rebuilt the calipers (cleaned pistons and bores)
Fitted new seals
Refilled and bled the system
The brakes now have pretty good power but they don't really come in until the lever is a long way back (about 1cm from the bar). Also it doesn't take too much strength to bring the lever back to the bar.
I have adjusted the span and I also think my lever is slightly bent (toward the bar) so that might explain why I can get it back to the bar.
So other than getting a new lever (on the case) what else is worth checking/swapping? I'm thinking master cylinder at the moment but is it possible it's still not bled properly?
How good are the standard brakes?
yorkie_chris
06-12-09, 08:40 PM
You haven't bled it right by the sounds of it.
Dave20046
06-12-09, 08:42 PM
How were they before?
Did you do new seals all round or just in the calipers/ mastercylinder.
I'd make certain you've bled them properly (sounds like you may not have)
as above..they need bleeding by sounds of it...also have u got braided hoses? if not they will sharpen up the feel a tad..my brakes work fine stop easy from speed 2 up;)
Dave20046
06-12-09, 08:52 PM
as above..they need bleeding by sounds of it...also have u got braided hoses? if not they will sharpen up the feel a tad..my brakes work fine stop easy from speed 2 up;)
you using standard pads lee?
AJB Racing
06-12-09, 09:00 PM
Hey Mate, I run a K4 SV in mintwins at a good level.
I had terrible problems with my brakes, i de-glazed them after every race, bled them till i went mad, fitted a brand new master cylinder from suzuki, fitted waving disks, fitted a banjo bolt to bleed from the master cylinder, then changed the braided lines.....
You know what... it was the pads all along. I changed to Performance friction pads and they were instantly better. Even at standstill they were really firm at the lever. Once they get hot they are phenominal (for an SV)on the track. Hate to say it but junk the EBC's and get some performance friction.
I replaced the piston seals but didn't touch the master cylinder.
It came back to the bar before too, although it felt a bit better before I did this work but it works better now...
Any particular bleeding tips? I have run lots of fluid through and been pumping in between opening the nipple.
I have tied the lever back to the bar (will be leaving it like that for about 20 hours) as I have been told this allows air to rise into the bottle, but not sure...
dave yes standard pads....i do remove em reg and clean em and give em a quick rough over( keeps em sweet)..oh and jynx, yes tying the lever up overnight does work wonders'..but have u fitted braided hoses?
beabert
06-12-09, 09:36 PM
i confirm tie your lever up overnight, job done.
AJB Racing
06-12-09, 09:42 PM
Sounds like you're bleeding it bout right. A banjo bolt that screws in the master cylinder is helpful. I always get a little bubble come out of that, that dosn't work it's way down the lines. Keeping the brake cable tied to the bar works well but i find the effect dosn't last very long at least not on the race track.
Braided lines would help heaps, i'd deffo change pads again to Performance friction, they really made all the difference for me.
I also now use ASV short levers, they are expensive but never touch the floor in a crash and ae also span adjustable on the move.
Ok I will report back tomorrow with the result of the lever tie! Thanks guys.
I run stainless hoses on the car and appreciate how much difference that can make, I think that will be an upgrade for next year :)
Fingers crossed!
Nicky S
06-12-09, 10:20 PM
I have been trying to sort out the front bakes on my SV650 (K4). The weren't particulary powerfully and the pads looked a bit glazed so I have:
Fitted new EBC pads
Rebuilt the calipers (cleaned pistons and bores)
Fitted new seals
Refilled and bled the system
The brakes now have pretty good power but they don't really come in until the lever is a long way back (about 1cm from the bar). Also it doesn't take too much strength to bring the lever back to the bar.
I have adjusted the span and I also think my lever is slightly bent (toward the bar) so that might explain why I can get it back to the bar.
So other than getting a new lever (on the case) what else is worth checking/swapping? I'm thinking master cylinder at the moment but is it possible it's still not bled properly?
How good are the standard brakes?
i had this same problem and did ever thing you have done i spent around £150 on bits and it was still crap so my last idea was the master cyclinder i ended up buying a brand new one from dealers as it was less hassle and i coudnt be botherd any more. it now works fine prob better then ever before
i also have braided lines make such a diffrence
the tie back of the lever will only work as long as your master cyclinder has not snuffed it. but then again it dose not allways work anyway
i tryed it and the next day my brake was fine i then used the bike and by the next day it was back to its crappy ways. i did this over a week tieing the lever back each night to see if it would make any diffrence but none at all
merlin427
06-12-09, 11:06 PM
Bike brakes can be problematic due to the relative height of the master cylinder to the calipers and the limited amount of fluid displaced by the relatively small master cylinder.
You could try using an ezi-bleed type system which forces the fluid constantly though the system rather than just a 'master cylinder' full at a time or bleeding from the caliper up. You get like a big syringe full of fluid and force the fluid up through the system.
I know you will get better performance with braided lines and different pads but the system should work fine with standard or decent quality parts.
Ok well tieing the brake lever back seemed to work quite well, the lever got harder and felt better (still not great) but after a 30 minute ride is seemed to go soft again..... *cough*
Is this sounding like master cylinder?
Dave20046
08-12-09, 02:12 PM
My first guess would be brake seals, however you've done them so guess that leaves brake lines or mastercylinder. I'd verify you're using the right mastercylinder (this was nicky S 's problem above) and then swap to braided hoses.
Have you bled the master cylinder?
Did you clean the sliding pins? Mine were so cacked up that I dont think the caliper could slide across fully and I had a spongy lever before. Also try bleeding your master cylinder at the joint with thebrake lines. Turn you bars so it sticking up and keep cloth round it to stop it spraying over your paintwork etc.
Didn't clean the slides but they felt quite free.
So just losen the banjo bolt on the cylinder, cover with a rag and gently pull the lever until fluid comes out there and then nip it off?
Do all ages of SV use the same master cylinder?
maclariz
08-12-09, 08:43 PM
No idea if this is going on in your case, but I had a problem on one rebuild where I used brake seals bought off ebay. It never would seal quite right. I eventually bought new pistons and seals from a genuine Suzuki part supplier and problem over...
Didn't clean the slides but they felt quite free.
So just losen the banjo bolt on the cylinder, cover with a rag and gently pull the lever until fluid comes out there and then nip it off?
Do all ages of SV use the same master cylinder?
I normally give the lever a couple of pumps, then hold the lever to the bar and undo the banjo bolt a little, and look for fluid coming out, then do the banjo bolt back up while still holding the lever in, as you would with the caliper bleed nipple basically. It's also worth giving the calipers and master cylinder a quick bleed just after leaving the leaver tied back over night as well.
Not sure about the master cylinder fitments on all sv's, but if you have a look in the stuff wanted section of the forum Grinch has put up a link to a site that gives you part numbers for spare parts, that might help you find out. HTH.
Well bleeding from the banjo and leaving the lever overnight helped but still not great.
Good news is that I just collected a lever, master cylinder and BRAIDED lines :D (Ebay bargin!) so there is a job for Saturday! Hopefully that will solve it, but it could be a while before I find out http://forums.sv650.org/showthread.php?p=2121258
Nicky S
10-12-09, 11:02 PM
Well bleeding from the banjo and leaving the lever overnight helped but still not great.
Good news is that I just collected a lever, master cylinder and BRAIDED lines :D (Ebay bargin!) so there is a job for Saturday! Hopefully that will solve it, but it could be a while before I find out http://forums.sv650.org/showthread.php?p=2121258
gdgd it is the same problem as me i had to change everthing untill i found out it was the master cyclinder
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