Fork brake lugs need cutting back !!!!

[Pigford]

I need to trim 4mm off the lugs that hold the front brake calipers to make them align with the discs (on me Harris - ZZR1100 forks).

They will need to be trimmed 4mm (where the caliper mates to the lug) and remain parallel to the original surface!

Is there a way to cut them (some drill attachment) so I can use my drill - some sort of counter-bore/router type thingy

I was thinking some sort of bar with a cutter attached, so the lug can guide it true At least the forks are soft alloy.

[j.wilson]

Havent I heard of someone using a similar cutter for trimming down the width of a swing arm. A counterbore drill with a solid pilot,...a cutter at its end- a bit of the bar pokes thru the cutter and you then make a plug for your lug so it run true.

Not sure which thread I saw it on tho.

Like this http://www.gjhall.co.uk/category/9

[kev edwards]

Maybe a pic or two would help with ideas for suggestions,

[zed1015]

Is it both lugs on eace leg ?
I would seriously avoid trimming the leg.
On the Z1R to fit R1 calipers to ZXR legs i took 4mm off the calipers which was easier .
It left 10mm + of thread remaining which is enough for a 10mm bolt.
That was over 12 years ago and i'm still running them - Everyday.
It will be easier to set them up on the pillar drill and use a piloted counterbore coupled with the drill depth stop.
You will need to rig up a fixture to mount the caliper parallel to the table.
Or just take them to the machine shop and let them do it on the miller.

[CAT3]

Definately a job for a milling machine. Unless it is possible to make some off-set caliper mounts.

[rodge70]

if using a router,use it inverted then find a way of holding leg parallel to cutter and move leg with a fence to guide it,bit hard to describe but makes perfect sense to me

[Pigford]

Thanx for the input chaps

The brake lugs have plenty of meat on them, so 4mm won't hurt - but I can't take it off the calipers, they're the Billet-6 Harrisons

May take them to a local engineer to suus out

[Rich]

I would not mill that much off the lugs if I was you. Have you thought of different offset disks, different yokes or an adaptor plate?

[Pigford]

Here's some photo's of the lugs......



I want to take 4mm off the left lug (as viewed in the above photo) - it's the bottom lug of on the leg, you can see the scratched mark in the upper bit of the lug which is 27mm thick - and will make an adaptor plate for the other mounting point.



Here's a shot of the caliper with a bracket I was going to modify, but not now!

[zed1015]

Won't do any harm taking 4mm off that protrusion as it isn't cutting into the main structure.

It's a straight forward job.
You could do that easily on the pillar drill with a piloted counterbore.

[Pigford]

You got it Rob - my explaination wasn't that clear coz I'm not sure of the engineering terms for the equipment

I have access to a good pillar drill, just need to know what/where to source the correct "piloted counterbore"

[zed1015]

Here's a set on ebay.
They look very good for the money but a search will turn up single ones.
I made some for doing the 8 plug heads and the oil feed mod i did on yours.
They are mainly for countersinking caphead bolts etc.
The center guides (pilots) are interchangable for different sized holes.
The cutter part is like an end mill and the pilot keeps them centered and square to the surface being machined.
Just use a 10mm pilot and the largest dia cutter to remove that 4mm.
With one of these you would have to try really hard to f"ck it up

http://www.ebay.co.uk/itm/220928214079? ... 1423.l2649

[Pigford]

Cheers..... will this do ?


http://www.ebay.co.uk/itm/Multistar-Mar ... 4600c3a2e6

[zed1015]

Didn't know you had a wooden leg

I wouldn't try it unless i had one lying about as a last resort.
You would be taking a chance as it's only carbon steel and it hasn't got the flutes for chip clearance so would probably leave a very rough finish.
It might cut the ally but can't see it making a good job and might even only last for one side.
You need to buy the proper thing ,those sets are HSS and a real bargain for all that's in there, Although i'd probably only use them for cutting ally as the whole set is the price you would pay for just one SKF/Dormer cutter.

[kev edwards]

I would go with Zed1015 on this one, it's a safer bet, even if its a little more exspensive.