Brake Bias Adjustment - Windle

[bruce moore]

sounds like worn out front tyre,or unequaled damping in the front shocks,my Ireson used to shake its head violently under braking,Trevor told me the front tyre was worn(cambered) i changed it and it was ok,ive even had a pogo motion before under heavy braking this turned out to be the rear shock had lost its damping.

[powerhouse]

You will probably have 2x 12" discs.if so there probably sponson engineering ones if so there the best, £700.00 a pair new to order if you can wait 5 weeks so keep em

Blimey Brian . . Sorry can’t agree, Spondon discs are ok but they are Stainless Steel, which doesn’t perform as well as Iron. Also if it’s a Windle, they will be either 280 or 320mm, Off the shelf from me at £420 a pair.

But I agree with others, initially it doesn’t sound like a disc problem.

Ahhh but mine are iron mate,they made a limited run for terry from the patterns of discs from sheen and schwantz bikes I was told by the owner. That's why there so expensive. The iron machining takes ages.

[oldbelly]

When I had Spondon discs on the Windles. ( one of them is your bike Brian ) they were steel and not as good as the P.F.M alloy that Wally sells now. Machining cast iron or an alloy of is very easy. Machining stainless is more difficult, (I was a turner many moons ago)

[powerhouse]

Hmmm very strange as I was told they were iron. They do get surface corrosion so I didn't question it. You will have to have a look when meet up again Geoff

[Whites]

I had a good look at the brake arrangement last night, it does appear that there is no bias adjustment. Once I figure out how to resize a photo on a blackberry I will post a few.

[Wal]

Hi Brian, don’t want to go all ‘nerdy’ on you, but although your discs could be Iron, they are more likely Steel.

Stainless steel is not totally rust proof. Although it is true to say that most ‘rust’ on discs is caused by metallic particles as in brake pad material, which will then go rusty.

Also, stainless as used in discs is normally 410/420 grade, being a fully Ferritic material and having a low chromium content, normally around 12-18% , it’s the chromium content which oxidises and forms the protective layer which keeps stainless shiny. (and slippy, which is why it doesn’t work very well as a brake material)

Anything else that ‘Aunty Wainwright’s Brake emporium’ can help you with sir . . . .

[Whites]

Here are the pictures, they don't look so great, sorry about that.

The disc is a spare one, but it is the same as the ones fitted currently, it is 11" diameter.

[Wal]

Hi David

That's not a disc. . . . . . .it's a hole carrier

As best as I can tell from the photo, that is indeed a Stainless Steel disc.

[steve-e]

That's not a disc. . . . . . .it's a hole carrier

[oldbelly]

Your outfit is one of the early F2 fourstroke Windles David, 94/95. The brake cylinder is a Tandem Nissin type and does not have a bias adtustment. I dont know how this is actualy legal as in two separate hydrulic cicuits but Terry used them for the fist couple of years and they worked ok. You will have to fit two separate cyinders if you want a bias.

[Eddy Wright]

Correct me if I am wrong Geoff. I think the Nissan tandem cylinder has a bias built in, if the brakes are piped up correctly the front get more pressure than the rear and sidecar.

[oldbelly]

I didnt think of that Eddy, come to think of it the brakes worked fine wet or dry although the front discs were smaller then, (when we were both a bit younger) lol.

[Whites]

Thanks for the replies everyone. I will check the head bearings etc, and if the brakes are still unstable we will have to manufacture a bias adjustment.

I recently found out that the previous owners moved the engine forward by 3 inches, maybe this is lifing the rear off the road and causing the braking instability. I can't really tell until we can do some pre-season testing.

[ACER]

What tyre pressure are you running?