'Lazy' SRAM brakes ...
 

  You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more

[Closed] 'Lazy' SRAM brakes when it's hot outside?

16 Posts
13 Users
0 Reactions
1,053 Views
Posts: 1879
Full Member
Topic starter
 

Anyone had this? With the hot weather, I've noticed my SRAM Level TLs - especially the rear - get sticky.

The lever won't return fully. I'm guessing the pistons aren't retracting completely. Only happens when the bike has been in the hot shed - once I get going and things cool down a bit then it gets better.

Well looked after, recent pads, been bled recently.

 
Posted : 26/06/2020 9:32 am
Posts: 2865
Full Member
 

my mates one do this apparently. I've not experienced it with mine but i've only had them for a week or 2!

my old oro`s do teh same. i presume its the lever material expanding and tightening up the seals.

 
Posted : 26/06/2020 9:34 am
 nuke
Posts: 5763
Full Member
 

Yep, had to drag my bike with Codes out the hot shed the other day...both front and back. Cant recall it with my other SRAM brakes (Juicy & Elixir)

 
Posted : 26/06/2020 9:35 am
Posts: 3445
Free Member
 

'They all do that, sir'
Will known issue, the plastic plunger in the lever swells in the heat apparently. You can remove it and sand slightly for more clearance, or but a replacement metal one from eBay.

The Level Ts on my jump bike do it really badly in the heat.

 
Posted : 26/06/2020 9:36 am
Posts: 167
Full Member
 

It's probably a master cylinder piston sticking (in the lever end). Had this on some Guide RS and googled it - it's a thing...!
Replaced the pistons with new units, which were 0.15mm less in diameter. No more sticking brakes in hot weather. Then I sold the bike.

Best option - junk the SRAM brakes and get something decent!

 
Posted : 26/06/2020 9:38 am
Posts: 8750
Full Member
 

My girlfriend's Guides have started doing this and I haven't gotten around to investigating it yet. Both levers are sticky but the rear won't return at all and stays floppy. This is nothing to do with the heat because the garage is like a walk in fridge.

So it's the pistons in the lever is it?

Best option – junk the SRAM brakes and get something decent!

That's what I've always done in the past but I've spent a small fortune on lockdown toys so far. I might have to see if the mrs. will pay half for some E4's since it's her bike.

 
Posted : 26/06/2020 9:40 am
Posts: 3445
Free Member
 

Best option – junk the SRAM brakes and get something decent!

I see this trotted out a lot. It's bollocks. Especially if you've had to replace multiple Shimano callipers.
Modern SRAM brakes are great, especially the Bleeding Edge system.

 
Posted : 26/06/2020 9:42 am
Posts: 167
Full Member
 

@submarined - I said decent, not Shimano. They used to be good, but I have also had to replace callipers on the 'new' XTs (8000 series on the SO's trail bike).

Have never come across decent SRAM brakes (but bizarrely my SO's Avid XO Trail on her enduro bike are great).

I run Hopes - not the most powerful, but reliable and very easy to live with. And not that I've had to, but can get complete service kits for every part.

 
Posted : 26/06/2020 9:48 am
Posts: 1879
Full Member
Topic starter
 

It's only been the last couple of days I've noticed, so a plastic piston in the lever that expands in the hot shed makes sense.

Not a massive issue, they soon cool down. Been pretty good otherwise, impressed with them.

 
Posted : 26/06/2020 9:49 am
Posts: 2314
Full Member
 

Some people file down the plastic plungers though the alloy replacement plungers on eBay cost about £8 and work great, will transform a lazy brake. Hardest part of swap is getting the circlip out of the lever.

 
Posted : 26/06/2020 9:55 am
Posts: 6856
Free Member
 

Some people file down the plastic plungers though the alloy replacement plungers on eBay cost about £8 and work great

This is 100% the solution to this. I think SRAM may have fixed this on newer brakes, but the older ones (E.g. my 2015 Guide RSCs) suffer with this. With heat, the plastic piston expands very slightly enough to get 'stuck' against the piston bore. I think this worsens over time too, perhaps the piston absorbs a small amount of oil over the years. It starts off as 'lazy' brakes but eventually they stay stuck on.

I fixed mine with a complete lever disassembly. It's not too hard to do, but it's fiddly and there are small pieces. I used this YouTube tutorial:

The main difficulty is getting the lever piston screwed back in, so I'd definitely recommend you try to find the specific tool SRAM make for this. I bodged it when I realised I had a lever in pieces and a ride planned for later that day (info on the bodge in the YouTube comments section). Sanding the piston down is easy and very effective.

My brake works like a champ now 🙂

 
Posted : 26/06/2020 10:19 am
Posts: 326
Full Member
 

It's usually the plunger in the lever. This is an issue on earlier models of Guide and I guess same with Level.

SRAM have fixed this but you need either the new model lever or get the updated service kit.

OR, DIY option is to file down the plastic plunger (videos on YouTube for this) or get the alloy replacements. It's such a common issue the Chinese have been knocking up loads of these.

Pulling apart and reassembling the lever is the main tricky bit. I don't know about Level brakes, but Guide has two types, RSC and the rest. The RSC needs a special tool to set the adjuster, although you can bodge it like I did.

 
Posted : 26/06/2020 10:57 am
Posts: 6690
Free Member
 

I sanded mine down and they work fine now. Decided to keep them (Guide REs) as I think they're are great brakes now they work. Much prefer them to Shimano and Hope are 2x - 3x the cost

 
Posted : 26/06/2020 12:08 pm
Posts: 1879
Full Member
Topic starter
 

Seems simple enough. Mine is def the heat. First thing this morning, brakes were fine. Checked at midday, lever for the rear hardly works. Moved the bike into a cold workshop, working again.

(pic from Amazon)

 
Posted : 26/06/2020 1:44 pm
Posts: 163
Free Member
 

So Sram have fixed this in later models? Anyone know when? I'd like to know if I buy a new set of REs, will they will come with the fixed lever?

 
Posted : 30/06/2020 3:40 pm
Posts: 0
Free Member
 

I believe it was a rolling change to production. Dunno if the fix worked 100%.

 
Posted : 30/06/2020 11:16 pm
Posts: 0
Free Member
 

You don't need to buy heavy metal pistons, the Taiwan plastic ones as long as labelled G2 work and fix this.

As before, I had to take a file to my circlip pliers and there was a LOT of swearing to get them out. Not convinced I wouldn't just buy new brakes next time - only did mine as they were the expensive ultimate ones and I had already invested in problemsolvers...

 
Posted : 01/07/2020 8:18 am

6 DAYS LEFT
We are currently at 95% of our target!