2016 Merida 120 XT Maintenance - Advice required on tools

sayso

Been riding for just about a year and nearly died when I had to get my whole drive train replaced at a cost of about £300.... decided i'd try to get better at maintaining/servicing my own bike.

Picked up some tools and have had my cassette and cranks off today - all degreased and cleaned up nicely.

However I couldn't get the Disc Brake rotors off (there are two different lock rings) and I bought a tool for the bottom bracket that said Shimano compatible but it is way too big.

With the rear rotor I have the correct tool but it is not long enough to fit over the axle. I have no clue what tool to use for the front disc nor the bottom bracket (or are they cups?). Can someone point me to the right fitting/tool to get the rotors and BB off? Preferably UK stockists and/or Amazon

Also the rear brake squeaks like crazy and there is a black ring on the edge. This happened a few months back and the local bike shop changed both the rotor and the pads. A few weeks later it is happening again. Any ideas on why this keeps happening - am I riding the brake to hard?

If I wanted to change the rear rotor what would be the best option - same kind of price range as the existing rotors which is about £30 I think. Would I have more choice (do I need more choice?) if I converted the rotor to one of those with screw fittings rather than a single unit?

The Rookie

The bottom one uses the same tool as a cassette lockring.

Not had the upper style but it looks like an HT2 tool would fit (stock or maybe the smaller XTR style).

cooldad

Front should be HT2 tool. I found a cheap one with a handle works better than my chunky socket version, which fouls on the rivets.

Rear - the spacer should pull off I think.

Do you drag the rear brake a lot?

sayso

The Rookie wrote:

The bottom one uses the same tool as a cassette lockring.

Not had the upper style but it looks like an HT2 tool would fit (stock or maybe the smaller XTR style).

Thanks is HT2 - Hollow Tech, what is XTR?

sayso

cooldad wrote:

Front should be HT2 tool. I found a cheap one with a handle works better than my chunky socket version, which fouls on the rivets.

Rear - the spacer should pull off I think.

Do you drag the rear brake a lot?

Where did you buy the tool - I would prefer a socket version though so I can get the correct torque.

I’ll check re the rear disc and the spacer when I get home.

Don’t know what you mean by ‘drag the rear brake” can you explain the term please.

Any idea on how hard it is to switch from a centre lock ring disc to one of the more common screw types?

Thanks

02gf74

The wear pattern on the rear disc does not look right. The wear should come to the inner side of the disc, do you have compatible calliper fitted or additional washer/spacers that have move the calliper outwards.

.there are adapters to convert splined disc brake rotors to 6 bolt but I believe there are two competing splined systems out there.

Rear wheel looks to be shimano format for which adapters are available..
.
Front looks like the more recent mavic format, which if different, I ve not seen adapters for.

sayso

sayso wrote:

cooldad wrote:

Front should be HT2 tool. I found a cheap one with a handle works better than my chunky socket version, which fouls on the rivets.

Rear - the spacer should pull off I think.

Do you drag the rear brake a lot?

Where did you buy the tool - I would prefer a socket version though so I can get the correct torque.

I’ll check re the rear disc and the spacer when I get home.

Don’t know what you mean by ‘drag the rear brake” can you explain the term please.

Any idea on how hard it is to switch from a centre lock ring disc to one of the more common screw types?

Thanks

Unfortunately the spacer isn't a spacer - it is part of the axle itself and won't come off - I need a longer cassette tool.

sayso

02GF74 wrote:

The wear pattern on the rear disc does not look right. The wear should come to the inner side of the disc, do you have compatible calliper fitted or additional washer/spacers that have move the calliper outwards.

.there are adapters to convert splined disc brake rotors to 6 bolt but I believe there are two competing splined systems out there.

Rear wheel looks to be shimano format for which adapters are available..
.
Front looks like the more recent mavic format, which if different, I ve not seen adapters for.

Thanks for replying. The wear is to both sides of the disc equally. I couldn't see any spacers and the hydraulic brakes were the ones that came fitted with the bike and haven't been touched since I got it. The disc looks well centered equally between the pads and the pads move freely when the brake is applied. ]

Perhaps the problem is the pads don't bite quick enough so the disc continues to rotate generating too much heat - so the pads glaze over?

02gf74

No, not what I meant. If you look at one side,the rear rotor, the grey colour stops just after the 4 small holes, it should continue all the way across the braking surface to where it ends at the big hole.

The Rookie

02GF74 wrote:

.
Front looks like the more recent mavic format, which if different, I ve not seen adapters for.

No its the Shimano one for 15mm throu axle hubs.

02gf74

Looks similar to mavic. The original shimano centre lock had internal splines so cassette tool fitted, these ones have splines on outside, maybe BB tool fits or needs specific tool.

Too much faff compared to 6 bolt.

The Rookie

The cassette type won’t fit over a 15mm, all in their tech docs.