SRAM G2 brakes – oops, lost all fluid.

… I guess that means I now have to replace the fluid. Is that what ‘bleeding’ means?

Please be gentle with me, I’m going to require klutz level help.

Do I need to get an official SRAM bleed kit? I don’t usually mind paying extra for official brand stuff, but the SRAM kit seems to be about £100, whereas others are about £20 – that’s quite a difference.

Are my brakes ‘bleeding edge’? I assume so, but it’s hard to be sure.

Is it as easy as it looks in the ‘how to …’ videos? Seems pretty straightforward, but I am often able to discover previously unknown ways to mess up seemingly simple procedures.

Should I just take it to my LBS instead?

I use to get the Avid/SRAM kits, now I just get what I need from epic bleed solutions. This is the kit you need:

Epic SRAM Bleed Kit & 100ml DOT Fluid – £24.99 – Epic Bleed Solutions

They have instructions on there too but combine with SRAM docs & youtube vids. Its easy if you follow the instructions and take your time.

How did you lose all the fluid?

Its no biggie with the right kit. G2 brakes will have teh bleeding edge port on the inside of the caliper. You wont find one on Shimano style at the top with a traditional nipple. Probably behind a rubber cover and dont loose this if possible.

Bleeding edge makes this soooo simple it is worth getting a kit, bleed blocks and the syringes.

Than best, watch the you tube video and note the adjustments before bleeding on the reach and bite position at the M/cyl end.

Doddy does a good version as well as SRAM.

Top tip to finish, slightly overpressure at the bleeding edge end for a nice firm lever.

“How did you lose all the fluid?”

You see where I said I needed klutz level help? My rear brake was a bit sticky. I thought the pistons might be a bit grubby – ‘no problem’, I thought ‘ I’ve cleaned pistons before’. So I removed the pads and gave the levers a teeny little squeeze, and out popped the piston, leaking all that nasty fluid everywhere.

It seems my shimano brakes, which I have cleaned many times, require a bit more of a squeeze than my sram brakes.

Next time, just put the 4mm allen key in the disk slot, and you will be fine.

Genuine SRAM kit every time, as it comes with bleed blocks, olives, barbs, loads of spare o-rings etc.

I’ve used a DIY kit for years and it has been good…recently went to the SRAM kit and it is better.
Both will work fine.
I’ve found degassing the fluid really does help – fill syringe half full and fully seal the nozzle, draw plunger back so it creates a vacuum and let all the bubbles rise to nozzle.
Fill from the caliper up to lever, then bleed caliper, then bleed lever. It basically ensures any air that is in the system is removed.
If you haven’t done it before then take your time and don’t rush.
It isn’t a difficult job, but don’t rush it.

It’s faffy the first time, mainly because it’s difficult to remember each stage, but it’s all doable at home, and gets easier each time you do it.

I’ve had the SRAM and the copycat kit. If I was buying again, I’d go for the SRAM pro level kit, just because it’s higher quality.

Thanks everyone so far, lots of useful advice.

I’ve just seen the SRAM pro kit on bike inn:

https://www.tradeinn.com/bikeinn/en/sram-pro-brake-bleed-kit-tool/137680569/p?tqw=

for £64, which is a bit more reasonable than I’d seen it elsewhere. I’ll be getting that I think.

I bought the SRAM pro kit from bikeinn, I think it was around £50 the day I ordered. It’s a bit of an outlay, but everything for every possible SRAM brake eventuality is in there and it’s good quality. Glad I got in now. When was learning to bleed my brakes, I liked knowing I had best tools I could have for the job and that any difficulties were my own failings, not the wrong (or cheap) tool for the job.

I also bought from BikeInn…only (mild) grumble was it took 10 days to arrive. Was aware it wouldn’t be next day (wasn’t needing it next day), but having ordered and then watched it sit at each stage made it feel much longer – should have done something else but I got hooked checking every couple of hours for an update.

BikeInn is in Spain, I believe. Wait aside, they’re pretty useful for some bargains since CRC went under.

I definitely reckon it’s worth getting your own kit and learning to bleed your own brakes – I’ve found pre-bled SRAM brakes to be highly variable from new and all better for a home bleed to some degree. Also, my LBS did a terrible of bleeding my Codes when they installed them. I just assumed they were meant to be that spongy until I moved them to a different bike and gave them a quick service and bleed.

The GMBN video was clear and straight forward IMO. There’s a few good ones on Youtube… just avoid/ignore anyone doing weird ‘special tricks’ like pumping syringes to purge hidden bubbles, whilst actually creating them. And not all G2 brakes are bleeding edge, but the pro bleed kit covers both types and the GMBN vid explains the difference.

I’m aware it might take a few days to get here. That’s ok, I’ll just have to be patient.

A few more questions:

How often do you need to bleed brakes? My gravel bike is about 5.5 years old and I’ve never done it. The brakes – Shimano on this bike – feel fine.

Will the procedure be the same as a normal bleed even though I have no fluid in the rear brake?

Thanks again, really useful info from everyone.

Shimano will be mineral oil, so if it feels good I think you can leave it a long time. My LBS manager, who’s generally pretty sensible, said Dot fluid is worth changing yearly. The theory being that Dot fluid absorbs moisture and if left unchanged for a long time will eat your brakes from the inside. Not permanent damage AFAIK, but a strip down and rebuild job.

When I resurrected my old G2s, the rear had been cut off the old bike and sat in a bag for six months, losing a lot of fluid. I had to do the bleed process twice, but I’m not sure if that was the lack of fluid in the hose, or my incompetence. Either way, same process and it’s solid now.

Hello again.

Kit arrived from Spain. The instructions confused me a bit as it turns out I don’t have ‘Bleeding edge’. Once I’d realised that everything went well. My brakes still feel a little spongy, maybe a little air got in when I was faffing about – I’ll do it better next time.

I have one more question that probably has an answer so simple I’ll blush:

When removing the syringe a fair amount of fluid escaped before I could replace the little screw. This happened at top and bottom, but more at the calliper end than lever end. I’d actually foreseen this and had positioned the calliper as best I could so that the fluid port was positioned upwards. I think that helped a little.
Is there some simple way to prevent this happening, or is it inevitable that some fluid will escape?

Anyway, thanks again for all the tips and advice. My pads will need replacing in the near future so I’ll give it another go then and I’ll do a better job.