Brake Lever - "Mechanical Advantage"?

[ianw]

Too much braking on the front end, eventually, braking hard enough & the back end will come round, like this-
http://www.youtube.com/watch?v=KESuZVIkUq8
I eventually got it right
Defo check the sizes of your discs?

[Whites]

Ok, I have 2x 11" discs on the front wheel and back and side both have a 9" disc.

[ianw]

Are the discs stainless or cast iron?What calipers are you using? I only have knowledge of Locheed.
Wal on here is your man for jap, etc caliper & pads knowledge.

[Whites]

I think the disc's are cast iron, as a magnet sticks to them. On the front I have lockheed CP3386 x2. Side and Back are the same, lockheed ones also, can't see the number clearly. CP2696-101C maybe?

[ianw]

Most stainless discs are magnetic, made from cheap grade stainless, Grade 303?? I think.
Great they are all Lockheed.
The cheapest & easiest way is different material pads & maybe grooving the front pads, we need Wal to chime in now with his advise on make of pad & material.

[Whites]

We are changing the current master cylinder (with built in bias) to a 2 master cylinder solution with adjustable bias.

Even if this doesn't fix our snaking issue, we figure adjustable bias is a lot better than fixed bias and adjusting via grooved pads etc

As for the brake lever I think we will try to use the current one, and maybe make a new one, based on the 7-1 ratio. As long as both levers are removable, and master cylinders are mountable in the 2 different locations, we can change to the one which works best.

The engine has been moved forward 3 inches by the previous owner, I can't figure out if this is contributing to the snaking issue. If you moved your engine forward and kept the brake bias as it was previously, what would the effect be on the brakes?

[steve-e]

Would make the back light.

[ianw]

Steve, possibly on a left approach but not on a right with conventional F2 forks, different on wishbone F1 front end

[steve-e]

Simple physics, if you move the weight off a wheel it's going to be lighter no matter what it is.

[ianw]

Big difference between a 10st rider & a 15st rider trying to give advice on brake & suspension setup Steve.
Solo forks, (which motorbike & sidecars ran in racing many years ago, , as you know ) F2 ( leading link ) & F1 ( wish bone )
Under braking there is massive differences in the way the suspension on the front reacts under braking forces.

[Whites]

Ok, this is what we thought also Steve. The engine being 3 inches further forward might not be causing the snaking, but it is definitely not helping, the back is lighter, more likely to snake under braking?

So it seems that the way to fix this is to adjust the brake bias, or move the engine 3 inches backwards. We decided to adjust the brake bias.

[Whites]

Big difference between a 10st rider & a 15st rider trying to give advice on brake & suspension setup Steve.
Solo forks, (which motorbike & sidecars ran in racing many years ago, , as you know ) F2 ( leading link ) & F1 ( wish bone )
Under braking there is massive differences in the way the suspension on the front reacts under braking forces.

I am around 14 stone, my passenger around 10 stone. Maybe this exaggerates the front heavy sidecar we currently have.

[G JONES]

What sort of brake setup on the front ? - calipers fixed to bottom loop or on floating plates ? - anyone checked the trail ? (Just a thought )

[ianw]

a big, big problem with outfits, whether they are F1 or F2 but with the engine in front of the driver & running leading link forks is that they have been over braked on the front end since the late 70's.
Massive discs with loads of "scaffolding " attaching them to the fork legs or bottom swing arm.
One chassis builder does it so they all follow.
George Hardwick & latterly LCR saw there was no need for massive double discs on the front-



One disc in the center of the wheel hub.

[Whites]

What sort of brake setup on the front ? - calipers fixed to bottom loop or on floating plates ? - anyone checked the trail ? (Just a thought )

I believe they are on floating plates, same as the ones pictured in the for sale section here. viewtopic.php?f=45&t=45121

We have not checked the trail yet, but it is something we will be checking.

Ian, surely the size of the caliper/disc on that LCR deliver's similar braking performance to a dual disc/caliper setup?