Linked brake's

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clutchspring
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Linked brake's

Post by clutchspring »

Hi , need some advice regarding MOTS & linked brake's .
Just been checking my Varadero over ready for the MOT & found out the rear brake's not working via the front brake which it should .
The rear break pedal is still. Operating the left hand front brake which it should do via the linked braking systems fitted to this bike.
Back brake still works fine as does the front , what I would like to know is would this be a MOT failure !

Thanks,
Ian.
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Cone
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Re: Linked brake's

Post by Cone »

Lol I’d be more worried about the fronts failing if the link has failed, not that I know anything about the brakes on a varadero

Seriously I wouldn’t sit on that
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AlanHolt
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Re: Linked brake's

Post by AlanHolt »

As the rear brake is operating itself and the front left, it sounds like a faulty delay valve (£190 part).
Current bike is a Yamaha T7
Stewie
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Re: Linked brake's

Post by Stewie »

I don't know if they are the same as the Blackbirds link brakes, but first I would be giving the system a service, but as said if it's not working as it should I wouldn't be riding it, as for the MOT as long as each wheel stops as it should it'll pass.
Jak*
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Re: Linked brake's

Post by Jak* »

I have no experience of Honda's system but every time I take my Guzzi for MOT I point out they the brakes are linked. They still only test the back and the right front disc and it passes every time on 2/3 of its braking power.
Cheers Jak
sprintster
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Re: Linked brake's

Post by sprintster »

I'd have thought if the lever stops the front wheel and the pedal stops the back it will still pass.Your brakes would have to be seriously shit to fail when you think a 30 year old drum brake can pass.
Tourider
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Re: Linked brake's

Post by Tourider »

The test is the same as for normal bikes, so the front brake lever is used to test the front brake and the pedal to test the rear.
Craig-SM
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Re: Linked brake's

Post by Craig-SM »

The brakes are tested independently so the tester would have no idea that the linked system wasn’t working.
herman
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Re: Linked brake's

Post by herman »

At my last MOT he tested with the ignition off which disabled the linked system after me telling him to watch out for the brakes. Passed obviously
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scotsy
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Re: Linked brake's

Post by scotsy »

Blackbirds CBS linked brakes only work like that when the bike is moving forwards.

The LHS front caliper gets 'rotated' slightly on a pivot fixed to the LH fork leg, this only happens when the wheel is moving forwards AND the front brake is applied. This 'upward' movement applies pressure into an extra master cylinder piston that is connected to the LH fork leg and rear brake caliper and applies some braking at the rear wheel.

A mate of mine had his blackbird fork legs powder coated and after refitting them he had a 'glowing' rear disc. It turned out that the 'LH pivoting caliper was too tight on the powder coated mounting lug and was sticking after releasing the front brake and therefore still pressurising the rear caliper which caused the rear brake to overheat and could have been very dangerous if it had gone unnoticed.

We sanded away the powder coating on this 'lug' and put a touch of copper grease on it so that it was free to 'pivot' again and it was cured.

ian
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