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Author Topic: Twin disk brake conversion  (Read 936 times)

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Offline Mr.Mazza

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Twin disk brake conversion
« on: February 25, 2019, 01:58:15 AM »
Hey everyone
I wanna stick dual disks on the old girl (750K4), now for some reason the right fork leg is already a disk leg! (Dunno why, lucky?)
I just need to know what differences on the right side of the hub there is, looking at it a different speedo drive?
Not concerned about brake lines ect I'll be making custom braided setup

Ill attach photos, any help appreciated  :)
« Last Edit: February 25, 2019, 02:00:36 AM by Mr.Mazza »
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AwesomeCB

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Re: Twin disk brake conversion
« Reply #1 on: February 25, 2019, 03:23:01 AM »
I'm not sure, but I vaguely recall this topic came up once, a long time ago... Maybe a search here might turn up something.
« Last Edit: February 25, 2019, 03:25:31 AM by AwesomeCB »
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Offline bryanj

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Re: Twin disk brake conversion
« Reply #2 on: February 25, 2019, 03:54:37 AM »
Look for the twin disc write up i did and you will see a picture of the speedo drive plate you need.

Go to manuals and technical and in menu at top right look under 500/550 then scroll down
« Last Edit: February 25, 2019, 03:57:50 AM by bryanj »
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Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline Mr.Mazza

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Re: Twin disk brake conversion
« Reply #3 on: February 25, 2019, 04:06:40 AM »
Righto so I had a search but the info is all over the place   :-\

Ive gathered the disc will bolt straight on, get another caliper plus arm ect

Do I just get slightly longer hub bolts or double ended studs to mount the discs?

And the speedo drive what actually does it need to be modified to fit into? I just find pictures of a metal thing and no further info

Thanks
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Offline bryanj

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Re: Twin disk brake conversion
« Reply #4 on: February 25, 2019, 04:49:44 AM »
Longer HT bolts with nuts and if you look at the hub on speedo drive side there are two flats machined on it. The original drive plate fits over the boss and is held by the chrome plate which has two pressings to hold two legs against the hub, the new disc has to bolt flush to the hub so the pictured drive is needed to drive from the milled flats, it was the original type on the VERY early 750 but due to slop the speedo wavered a lot and Honda modified it. With the second disc you frequently need to remove a small amount at 4 points on the inner of the disc carrier to make rectangular slots for the drive legs to go in with stops the movement anyway.
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Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline flybox1

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Re: Twin disk brake conversion
« Reply #5 on: February 25, 2019, 06:36:45 AM »
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Offline MauiK3

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Re: Twin disk brake conversion
« Reply #6 on: February 25, 2019, 08:04:33 AM »
Yamiya sells a fastener set to hold dual discs with very nice nuts that are thinned. They also have a speedo drive.
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Offline Mr.Mazza

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Re: Twin disk brake conversion
« Reply #7 on: February 26, 2019, 08:51:23 PM »
Alright looks pretty simple thanks guys
Just gotta find a set of calipers, restore them and start mounting them
Cheers
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