Author Topic: Yam DT1 front brake cam improvement?  (Read 10581 times)

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Offline John Orchard

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Yam DT1 front brake cam improvement?
« on: August 11, 2024, 05:27:39 pm »
Hey Guy's, does anyone know of a front drum brake cam that will work in place of the stock cam on a DT1 (and just about any Yam dirtbike from '68 to '76), the actuating pad between the brake shoes has a very gentle action, causing a spongy lever action. I guess I could weld a bead of weld across my stocker but I'd rather find something that will bolt-in from another model if possible.
Johnny O - Tahition_Red factory rider.

Offline PeterC

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Re: Yam DT1 front brake cam improvement?
« Reply #1 on: August 12, 2024, 08:06:38 am »
Can you measure the appropriate dimensions and post them.
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Offline sleepy

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Re: Yam DT1 front brake cam improvement?
« Reply #2 on: August 12, 2024, 10:24:34 am »
Have you checked everything else? I have an RT3 that I ride on the road and the front brake is quite good but when I tried to use an after-market cable it was super spongy.

Offline John Orchard

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Re: Yam DT1 front brake cam improvement?
« Reply #3 on: August 12, 2024, 08:58:44 pm »
I think I've found the issue, the elcheapo shoes don't sit central in the drum, when I lock the brake on, with the shoes in the hub, I can't slide the axle through, as I release the brake pressure, then the axle will slide through ...... hmmmm.
Johnny O - Tahition_Red factory rider.

Offline pokey

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Re: Yam DT1 front brake cam improvement?
« Reply #4 on: August 13, 2024, 11:37:09 am »
Yam brakes usually work quite well and not uncommon to find them on early Suzuki as they do fit the fork lug.  Likely nothing you dont already know but guess its the basics with inspecting the hub for roundness grooving glazing and take appropriate action. Not getting decent brakes from a slightly worn shoe is a sign the hub is out of spec. As you can see with a single pivot only one end moves unlike TLS so making sure everything is within spec so you get the most contact with the hub that may need relining. I hear metal spraying them is the way to go. Changing or packing the cam will only give you a different feel as the shoes still travel the same distance and path. One other thing to look at is some bikes have different length shoes in the same hub so check installation is correct. Best of luck with them.