Education We Like to Ride Bicycles

I have a stock Trek Mamba 2012 and I want to upgrade the rotors to shimano 180mm or 203mm. Where do I start? Can my current components handle the added stress? I ride everything (road, mountain, downhill) with it.

I'm guessing I need the new rotors, adapters and maybe different pads?

 

Bigger rotors may invalidate your warranty.

But depending on what brakes you're running yes, rotors and adapters. Most branded forks should be okay with a 180mm up front, and I'd imagine that most frames should take a 180mm at the back.

What size are you running front and back currently (sizes plus type of brake)?

edit 1 - Looking at this, it looks like the fork is post mount, the rear is IS to post mount and that the brakes are Shimano's.

You'll need something like this to take the front up in size (i think this is a 203 adapter). Something like this (180mm) or this (203mm) to make the rear brake bigger. Then you'll need your rotors.

Be careful at the rear as a 203mm may not have the frame clearance

edit 2 - one thing I forgot to mention is that a lot of adapters usually run on a +20mm basis, so depending on the size of the front rotor (think 160mm/163mm), you would need a +20mm adapter to take it up to a 180mm/183mm or a +40mm to take it up to a 200mm/203mm.

edit 3 (just to save posts) - mwahahahaha I beat the great Malvolio. lol, that makes you sound like a magician.

 

My first question would be: why do you want larger rotors? What do you perceive as the benefit, or is it aesthetics?

Keep in mind that even in top-level DH, rotor sizes are getting smaller not larger. This is mainly because the benefits of larger rotors are often negligible and more in the riders mind than anything else.

But if you feel the need to do so, then here is what you will require: rotors (6-bolt), adaptors appropriately sized for the rotors (IS-post for the back, post-post for the front), and new brake pads would be recommended for the best performance.

And yes, your bike can handle larger rotors, even though you will void the warranty.


[Edit] - Gah! Cookie beat me to it.


Did I hear a request for bike porn? Okay.


Larger version on dA.


Larger version on dA.


It's always bigger on dA.


Embiggen on dA. This was one of them random ideas I had, and should have the caption "Your bike loves you, though it isn't always obvious".


View it on dA. This is what my rear tyre looks like at the moment; and yes, you are seeing the internal thread structure of the tyre itself. I expect to get another week or so out of it before it explodes.

 

With 203 front and rear Juicy 7s on my bike, I'd say don't bother with 203s. There's more power available than I'd ever need, and it just makes it easier to lock up. I've locked my back wheel up more times than I can count when I'm not paying full attention.

Why do you want to put bigger ones on? Would it be better to first try some different pads if your looking for more power?


*EDIT*

Ninja'd by Malvolio,

 

I run 203 front and 185 rear but have my levers setup for one finger braking. Avid Code brakes. Superb modulation from this setup.

 

I do a lot of single track and never seem to have enough room to brake. I am not locking up now and would think I could feather the brakes enough with a larger rotor to provide that stopping power without locking up. I could start braking a bit earlier but I ride to break records lol. Many a times I have flown over an embankment because I couldn't make the turn at speed.

I have no problem being told I am upgrading for a stupid reason. If brake pads help more, I will go that route. I am a beginner in this sport and will listen and read everything..probably why I have the larger rotor size in my mind(i read it).

I ride this kind of trail mostly

 

If you have plenty of grip on the trail, you may find benefit with a larger rotor, but for the most part a big rotor is just a bit heatsink more than anything. Plus as others have pointed out there is often less modulation due to better leverage over the wheel through the larger size.

For your situation I would probably try a better set of brake pads, or even consider just a better suited set of tyres giving you more braking traction. To me it doesn't sound like larger rotors are going to do much of anything for you other than destroy the trail (feathering powerful brakes is really difficult by the way - this is why the 8-pot Gator brakes never caught on, as the brake lever could easily be replaced by an On/Off switch). Thus should you so decide to stick with your idea of larger rotors, only step it up one size not two (180/185mm rather than 200/203mm).

Just keep in mind as well that slowing down is often the quickest way through most trails. Do you watch Top Gear? Know how Clarkson often will say that a slow run on the track is often the fastest? Yeah, same principal.

 

Also ill add ive just gone from 160mm mechs to big hydros it takes a bit of getting used to in terms of braking. Can I ask what brakes do you have at the moment? It could well be pads, something contaminating them or the disc or a simple adjustment.

As mentioned you'll probably be fine with going to 180/185s. Also are your discs six bolt or centre lock?

 

Morning all.

I've been thinking about getting some bike insurance. I know my contents insurance can cover the lose of a bike but I also want it to cover accidents.

This has all popped back to the front of my mind after having a near miss over the weekend when a woman in her bright yellow Seat Leon didn't see me on the roundabout until the last minute. I didn't get hit but it was enough to make me think.

Any suggestions of things I should consider and companies the specialise in this?

 

I had a look into this before and in the UK it kept on coming back to Cyclegaurd who, if you Google, seem to have a terrible reputation when it comes to dealing with theft. Most advice was get good home insurance that covers your bike. For cover against accidents I have no idea.

 

Adding my bikes to my contents insurance at home literally doubled my premium So I didn't do that. Evans have an alright look insurance plan that isn't that much money - it's just evans and they have irritated me to the point where I don't want to give them any money, so I am on the look out for some special bike insurance as well.

 

The brakes are stock 2012 mamba so i'm guessing it has Shimano M446 hydraulic disc brakes. I have no idea if it is six bolt or centre lock. I see the bolts but I figured the rotor was a two piece or something.

It looks like I have these rotors:

 

I'd imagine they are 6bolt rotors, center lock rotors slot onto grooves cut into the hub then are held in place with a similar lock ring to the one holding a cassette onto the rear freehub.

 

is it possible to buy anywhere the little conical springs from qr skewers without having to buy new skewers? As I need some!

 

Yes it is, but it seems even the mighty CRC doesn't list them - strange that. Walk into your LBS and see if they've any kicking about, as more than likely they'll just have a bin of them somewhere, if not just some old half-broken skewers the springs can be stolen off.

Though if I'm honest the centring springs don't do a whole heck of a lot, so feel free to just remove them entirely.

 

Update on the bike. Finally finished sanding it down. I took it to a workshop but they wouldn't let me use their sandblaster because they didn't want it full of paint. They were pretty cool though and gave me loads of abrasive and my own bench to work at.



First stage was primer, then we painted it white (outside, in the dark, not so clever...):



Then we cut out lots of little circles of sticky backed vinyl to use as a mask and stuck them all over the frame:




First coat of crappy halfords spray paint:



And second coat:



Then we peel off the mask and...



and with 2 coats of lacquer on it:



That's all for now, will rebuild when lacquer has hardened tomorrow night.

 

Very nearly Mr Blobby paint scheme, .

 

I was hoping that would be what you said as I don't currently have any on mine!

 

I looked into several different companies offering bike insurance and they were all linked to Cycleguard in some way. How ever from some more googling yesterday it looks like Hiscox underwrite a few different schemes such as this one. It's worth noting from the forums I have read you need to have a lock which they approve of and you need proof of ownership of that lock. I.E. if you already own an approved lock but did not keep the receipt they might not accept the claim.

 

As far as I've ever been able to work out, their purpose is only to keep the skewer centered, making it easier to fit a wheel into the dropouts. Running one usually makes it slightly more of a pain to install a wheel as the skewer is pulled off center.

As Malvolio says, walk into a LBS, I know I have a few kicking round the shop. There are a few online stores selling pairs of Shimano ones for roughly £1, but they are all out of stock which would tell me that the main UK Shimano importer (Madison) is also out of stock.