Soggy rear brake after caliper replacement

[xsel777]

I imported a used rear caliper from ebay, since it was R3000 cheaper than a new original.
I took the scoot into to a local bike  workshop to have it fitted since I did not want the hassle of bleeding and cleaning up brake fluid.
However, the scoot came back with a soggy brake. Rear.
The job did sort out the major chatter that was happening before as the old caliper was badly worn.
I decided to bleed myself, and used a syringe to push the fluid up onto the reservoir. 400ml later and hardly any better.
Since the caliper is the only different thing, must I assume that this used caliper has bad seals or something, although there is no evidence of fluid in the caliper escaping.?
The brakes were sharp before the caliper change.
I am one man alone, so bleeding the rear brakes is difficult as I can't pump and release the nipple (I can't stretch that far), which is why I used the reverse syringe idea.
Any suggestions?

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[CROSSBOLT]

The big deal is getting the air out of the brake cylinders on the caliper. Often the caliper needs to be tilted in either pitch, roll or both to really get the air out. This would have to be with the caliper off the bike but connected to the brake line. The hard part is hanging on to everything while you pump fluid and not to overflow the master cylinder. It takes planning and rigging to make it possible with one man.

[Stig / Major Tom]

A mightyvac?....for one man bleed.
Works for me.
Stig

[stuo]

"Soggy brake" is air in the line. Sometimes it cures itself with time and use. If not, you must bleed the line. Have someone keep the reservoir from going empty while someone pumps the brake hard a few times and while squeezing the handle down open the bleeder valve, then close the valve while holding the handle down (so you don't suck air back in the line). Let the handle up, refill the reservoir, repeat several times. Put a container under the valve to catch the fluid as it burps out of the valve or attach a piece of tubing to the valve to a container if you want to avoid the mess. Brake fluid will dull paint so avoid splatters.

[hypophthalmus]

When I had to do this, I was able to enlist the help of someone with no mechanical experience at all to operate the bleed valve. I just told them when to open and close it, and instructed them to close it snug, not tight. It worked out well for me.

[gwdoiron]

Spongy brake and no evidence of leaking brake fluid = air in the hydraulic system.
The mechanic who replaced it didn't fully bleed the brake line.
I bleed at the caliper until no air comes out (this is awkward using a mightyvac because the caliper and brake handle are on oppposite sides of a bike, much quicker to use two people).
Then remove ALMOST ALL the fluid from the reservoir and compress the caliper piston (with a C clamp) all the way down (removes any air trapped near the top of the brake lines).
Then re-attach caliper, add brake fluid to reservoir, and pump brake, adding fluid to reservoir after every few pumps to make sure that you DONT run out while pumping, until the brake pads seat.  Top off fluid and close up shop.

As a side note, on my Xciting 250, which has linked front/rear brakes on the left brake handle, I have *never* been able to get the left brake handle to feel like the right (front brake) one, it seems like it just needs more travel to put the same amount of force on the brakes.  I spent almost an hour bleeding it (across two days) at the calipers, the distribution relay, and the reservoir.  It isn't "squishy" in the sense that it doesn't "firm up" after a few pumps, its always like that, so I think I don't have air in the system, it just works this way.

[xsel777]

Update : I have done nothing further, but every day since, it is getting better. I have ordered a vacuum bleeder, but no hurry required now.

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[MJR]

I've heard of people clamping the brake lever down overnight and having sucess, you might try it.