Disc Rotor / Caliper Sizing for my SID's

[Wylie]

I was thinking about getting a front disc for my 2004 Sids but was wondering if anyone can help me work out what size i would need (without the use of adapters etc).
I've seen a few old 5 bolt hope rotors and brakes on gaybay but i just don't have a clue what size i would need.

Cheers,
Wylie

 

[Rampage]

I've got a 5 bolt Hope 155mm disc, an Avid Juicy disc brake using a Tektro adaptor.

I think anythings possible using washers and trying different adaptors.

 

[Wylie]

I've got a 5 bolt Hope 155mm disc, an Avid Juicy disc brake using a Tektro adaptor.

I think anythings possible using washers and trying different adaptors.

cheers m8, it's just that i'm kinda wondering what size disc the fork was intended for without adapters etc

 

[Xesh]

If you use an IS mount then the rotor size is dependant upon the calliper type. That said SIDs were/are XC forks so a 160/165mm rotor would be the norm (although you could quite easily use a 180mm).

 

[Wylie]

Thanks man, must seem like a bit of a noob - but i've never run discs and it's all pretty confusing ...including all that whole C2 caliper numbering system. I dont even understand that "bigger disc on the front than on the rear" thing either ...need more modulation in the front or something?

 

[02gf74]

I dont even understand that "bigger disc on the front than on the rear" thing either ...need more modulation in the front or something?

The bigger the disc (think of it as a lever) , the more stopping force you get for same pressure on the brake lever.

Since most of the stopping is done by the front wheel, it is usual to run a smaller disc on the rear.

Fitting a larger disc puts more force onto the forks so for those SIDs, generally you would not want to go beyond 160 mm.

Your fork takes IS mount and front caliper will run with 160 mm disc without an adapter; if you want 180 mm disc, then you would need an adapter.

I do not know what size disccs are availalble for Hope 5 bolt hubs.

 

[Rampage]

Chain Reaction sell a few 5 bolt discs.

The front is bigger because braking is more effective on the front and your less likely to skid. A car is the same.

 

[MikeD]

Is that a Big'un hub? On a SID?

 

[Wylie]

Much Thanks for all helping to clear a few things up for me, but what is all that C2 Number system about?

...oh, and yeh, Big'Uns F&R

 

[Rampage]

C2 is a model of disc brake made by Hope.