One of two pistons is being stubborn.

[Beehive Bedlam]

My front pads on my varadero 125 need to be replaced I've just attempted to change them before I go to work but one of the pistons is stuck I don't think it is seized as I can push it in slightly with the power of my thumbs. I understand they should be able to be pushed in with ease but this isn't the case so I have just put the old pads back in. I'm going to need to get them out to clean and polish them I don't have any dot 4 or time today so this will have to be postponed until Friday.

When I do get them out do I need to replace the seals also? I replaced the seals only about 5000 miles ago most of that has been on salty roads though but I have gave the pistons the occasional squirt of brake cleaner.

[gavcarter]

wouldnt have thought so - but you wont really know until you get the pistons out and look at the seals properly

[Beehive Bedlam]

[gavcarter]

rough patches, scratches, dimples, raggy edges, some ares may have lost there flex and done compress or bend aswell as others.

You may find that after a quick wipe they look virtually brand new.

If your not loosing fluid, or having any braking issues, and the seals look in good condition re-fit them - carefully.

It's usually recommended to replace them if the piston is removed regardless of the condition though.

[baldy]

Did you take the cap off the fluid reservoir before you tried to push the pistons back in? The fluid has to go somewhere. I've done this myself. I felt a bit silly when I realised.
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One day i will rule the world, just not today.

[Beehive Bedlam]

[weasley]

Loosen the cap but put some cloths or rags around the reservoir, because as you push the piston in it will push fluid back to the reservoir. If you don't keep an eye on it it will overflow and spill all over your bars, cables, tank, engine cases etc. If the fluid level is getting too high, suck a little out with a pipette or syringe.
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Yamaha XJ600 | Yamaha YZF600R Thundercat | KTM 990 SMT | BMW F900XR TE

[Nexus Icon]

[delsol]

[Beehive Bedlam]

Still having difficulties with the master cylinder cap off I can push it a few mm but then it just comes back out? Any other suggestions or do I have to take it apart and polish them back to life?

Here are the current pads

https://oi59.tinypic.com/2n7o7rm.jpg

Here is the cow


https://oi62.tinypic.com/24ouiy9.jpg

Note they do look fubar in the pictures but the pitting and teeth marks are on the very edge of the pistons which don't pass the seals.

Also I had to split a rusted knackered screw which wouldn't take the screwdriver with my swiss knife. I've duck taped over it and the saw marks until I source a replacement cover it is held in with one screw at the moment will it leak/rain enter the reservoir?

[Nexus Icon]

I'd use a couple of pieces of flat bar and 2 G-clamps to compress the piston myself but it sounds like it might well be fubared if you can't move it with the cap off but can move the other one.
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Greetings from Shitsville!

[Kickstart]

Hi

Use a G clamp to push the piston back in.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[Beehive Bedlam]

When the mechanic used a G clamp and started going at it with pliers and clouting it with wrenches to get it back in right before my eyes because it is 'just a 125' they started badly blinding. In the end I just replaced the seals and polished the pistons back to life myself they went back in silky smooth.

[c_dug]

G clamp should be fine, it just presses from the top of the piston.

Pliers on the other hand should be punishable by death unless the pistons are being thrown.

It is possible to get the piston slightly off kilter and then it is a right royal pain to get it to budge, maybe try getting it to move out a tiny amount first?
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I am a bellend, I am a man of constant sorrow, I am a gummy bear, I am a rock.

[Beehive Bedlam]

75mm G clamp from screwfix £3.99 did the job with ease.

I have a new issue now though the lever is very spongy I can almost hit the grip when I apply it defiantly won't stop me in an emergency stop.

The fluid is very dark and murky so I went to get some brake fluid got my 8mm spanner tried loosening the nipple and the head snapped clean off with hardly any effort. I must of over tightened it last time more than likely it was made out of cheese though.

Is there any way I can bleed the brake without using the nipple? I am aware you can get banjo bleeders but that will mean waiting for it from ebay.

[gavcarter]

[Beehive Bedlam]

I'm going to source two new screws for the master cylinder lid tomorrow and the most expensive bleed nipple I can find.

I will have a go at tapping it around with a screwdriver and toffee hammer there's only a tiny nik pointing out where it snapped off the thread though. I don't have a bench or vice so I will be attempting it whilst it is still bolted to the leg.

If this fails I will have to take it to a garage as I also don't own a drill or weld gun.

A new calliper is out of the question I can not find one on ebay/gumtree.

[ws4936]

https://www.ebay.co.uk/itm/371027684167

Hoped you cleaned them pistons up.
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If everything seems under control, you're just not going fast enough.

[Beehive Bedlam]

Extremely foggy and moist in the air today riding from work the food bag over my master cylinder had a lot of condensation in from over night so there's bound to be a funky cocktail in the system now.

Would my brake instantly stop working or gradually get worse? I doubt I will be able to remove the stud a bleed it today because it's forecast showers all day my workshop is the garden.

[TUG]

(Shakes head) The brake needs a service, seals out, clean grooves out, clean pistons, replace fluid. It's that simple, new brake just like that, you might get stuck if you let the seals swell up but replacing the seals is often cheap anyway.
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Haz ER-5, innit!

[mudcow007]

why dont you just buy a 2nd hand caliper from ebay an stop pissing about**

125 calipers are only about the size of a mountain bike calipers, so cant be that much?

plus you will get another set of pistons etc


** edit**

ok i didnt read all you posts, these seem to be carrying a few bits for yours

Hills


breaking 1

breaking 2

[TUG]

[gavcarter]

[TUG]

[gavcarter]