Shimano M315 hydraulic brakes

[DouglasXK]

I’ve just converted a brand new Giant LIV hardtail bike with these brakes fitted. I’m 14-15 stone in weight. They appear to be correctly adjusted etc. However, coming downhill over extended distances >0.5miles and quite steep (required maximum assistance and lowest gear to climb) the brakes are being fried.

I need to correct this, any suggestions?

The brakes require resin pads to be fitted which I assume they are.

I have a similar problem with a set of Tekno Auriga brakes on my Boardman road bike but there is no such restriction on the type of pads used so I’m progressing from resin to sintered and soon to ceramic or “professional” - basically more expensive to see if one type will work.

 

[Fordulike]

What size rotor are you running at the front?

 

[Nealh]

I use Shimano BR- M series brakes up to M525 which all use the same B01S pad and very similar callipers without issues.
To prevent over heating modulate the braking down hill to prevent heat build up and don't allow speed to build up like a loony, as Ford has eluded to a larger rotor will dissipate heat better.

 

[Russelliow]

I changed 180 front rotor with deore caliper to a 203 rotor with zee caliper and its a lot better.

 

[DouglasXK]

What size rotor are you running at the front?

160mm

 

[Fordulike]

160mm

Just wondering if it's possible to run a 180mm rotor on your set-up. This should allow for more heat to be dissipated by the rotor and not the pads.

Whoops, teach me not to read the replies after my last question

 

[Fordulike]

The brakes require resin pads to be fitted which I assume they are.

Flay me alive for even suggesting this, but you are using branded pads and not some cheapy knock offs?

I'm running a basic hydraulic Tektro 160mm set-up, with genuine Shimano pads, and never had any bother, and I'm pretty harsh on them.

 

[Nealh]

I use knock off cheap pads, no issues with heat or stopping power.

 

[DouglasXK]

Flay me alive for even suggesting this, but you are using branded pads and not some cheapy knock offs?

I'm running a basic hydraulic Tektro 160mm set-up, with genuine Shimano pads, and never had any bother, and I'm pretty harsh on them.

They are as Giant supplied them.

The Tektro Auriga pads on the Boardman however are not Shimano. I am experienced enough to know not to mix pads and discs so I will follow your advice and thanks.

 

[DouglasXK]

Just

Wondered if it's possible to run a 180mm rotor on your set-up. This should allow for more heat to be dissipated by the rotor and not the pads.

Whoops, teach me not to read the replies after my last question

This is good advice, thanks.

The forks will take up to 180mm discs and a simple adaptor is required to fit the caliper. I’ll do the fronts only.

Thanks for your help.

 

[DouglasXK]

The discs are now 180mm, Deore-Zee, and Including the adaptor, total cost £16 (ChainReactionCycles). Too early to say if it is an improvement, the discs haven’t bedded in yet, but it is certainly no worse.

Many thanks, especially to Ford, to all who responded.

 

[seosamh1977]

I've personally never been happy with low end brakes, they just don't have enough power, and overheat far too easily. Got an SLX front on my non ebike mtb, and it's awesome. It's defo worth spending a decent amount of money on decent brakes(particularly the front, back doesn't need as much power). They get much better the more you pay imo.

You should try going up to 203mm if you are going to go up in rotor size firstly btw, it's usually just a case of buying the correct adapter for the type of mount your fork has. Bigger rotors should give more power.

 

[DouglasXK]

The fork won’t take 203mm rotor and they don’t recommend doing so unless you have a 12mm ? axle bolt.

Now that it’s bedded in I’m really quite happy with 180. They don’t tip me over the handlebars but it does work quite well!

 

[seosamh1977]

fair enough, yeah I wouldn't go over the fork rating. yeah the 12mm axle bot through is common on bikes these days, mine has a 20mm bolt through, makes things a bit stiffer.