2000 SV650 Front Brakes

[bergj1986]

I just picked up a 2000 Suzuki SV650 off CL. It's an awesome bike and I love everything about it, except... the front brakes are very touchy. I replaced the fluid today, bled all the air out, but my problem still exists. The brake lever is rather hard to pull and the bite is very digital. By digital I mean, when you pull the lever you get nothing...nothing...nothing...BAM, lots of brake. The brakes seem to be grabbing very hard and very quickly. There is also little lever travel. I've tried adjusting the starting point on the brake handle, but that doesn't really do much for this problem. The lever seems to move freely and there is no air in either calipers. I know the brakes are more than capable of stopping the bike, I'm just worried I'm going to get unexpectedly thrown over the bars because of the "digital" nature of the front brakes.

Anyone got any ideas?

Thanks,
Josh

[GixerJockey]

My new track bike has a similar situation with the front brakes. Very little lever travel and "all or nothing" brake delivery.

I have flushed and changed the fluid. I have also rebuilt the calipers. So I know that both of things are done properly. The issue still remains. I'm going to change out the master cylinder soon. It should solve my problem since everything else in the system has been changed...

[bergj1986]

But what I want to know is how is this possible? It seems like there's a goof up in some ratios or something like that. I'm used to bikes with a very modular feel in the brake lever, the harder you pull=more braking pressure. I don't understand how small inputs could lead to large outputs, the pressure simply isn't in the brake lines. Could it be hardened seals in the master cylinder? The piston on mine seems to move freely. Something just doesn't add up.

[bergj1986]

Just had an idea... do the calipers on this bike use sliding pins? If so, maybe the pads are getting stuck on a groove in the pins. They pads will slide on the pins until they hit the groove, then pressure will increase in the line because you're pulling harder on the lever. The pads finally slides over the groove and because of the increase in line pressure, the pads grab the disc very hard.

[vintage ex race]

It could also be the pad compound, some pad compounds react differently,some grab better with heat, and a hard lever isnot a bad thing, as long as it is moving fluid through the brack system check the pads.The pads I have on my sv race bike are like that until they get warmed up,then they work smoothly like you would expect.

[vintage ex race]

Also has someone replaced the break lines withSS lines? this would make a harder more possitive , firmer lever.

[davemon]

I'm no mechanic but since no one mentioned throwing some lithium grease or similar on the brake lever pivot I will. If you haven't tried that give it a shot. Worked on my CBR600F2 when the brake felt sort of on or off and was hard to modulate. Not as big of a deal as a well lubed throttle and throttle cable but could be cheap and easy.

Dave

[brady]

does it have the original master cylinder or a replacement? my guess is it's the pads, though, or built up material on the rotors.

[nt650hawk]

Massage the pistons on the caliper.
1. Pistons are sticking.
2. Remove 1 caliper.
3. Remove pads.
4. Clean (Simple green + tooth brush)
5. Push pistons in. (this will be hard at first but will get easier)
6 clean
7. Squeeze brake lever. (See pistons move)
8 clean
9 push pistons in.
10 keep repeating --push pistons in +squeeze brake lever

you do not want the piston to pop out. Do not let the pistons extend more than 1/4". All pistons should roughly move the same amount when the brake in squeezed.

Assemble pads and mount on fork.
Repeat to other side if you have a dual setup.

Before you go on a ride squeeze the brake lever to set the pistons.

[OreoGaborio]

+1 to Gino & Davemon.

If that doesn't solve the problem, switch pad compounds.

If that doesn't solve the problem, go back to the stock rubber lines if you've got SS lines on there. SS lines reduce feel by increasing firmness.

[bergj1986]

So I think I fixed the problem. I took one of the calipers off and noticed that one of the pistons was being pushed out more than the other. I twisted the pistons around which made them move easier. I cleaned the surround of the pistons and put the caliper back together. The pads looked fine. The brakes work much better now. Thanks for everyone's help!