Engineering question

In the continuing saga of trying to use the pair of 16.5" Dymags that
I have on the Team UKRM racer, I've run into a problem with the front
discs.

The hub dimensions are identical to those for the 17" wheels, meaning
the standard discs (or EBC or other replacements) would bolt straight
on. Except that the hub is drilled and tapped for 6 holes instead of
5.

I've a number of spare EBC disc carriers (to which the rotors attach,
using floating 'buttons'). Would it be feasible to fill the holes in
a carrier with weld and re-drill for 5 holes?

Can anyone think of any other potential solutions?

 

sell the 16.5" wheels and buy more 17" ones.

 

The wheels are magnesium alloy, so failry Trick Stuff.

They are already drilled 18 times, with every third hole having a
helicoil insert. No scope for siting additional holes nearby.

In fact, the radius of a circle bisecting all of the mounting holes is
a relatively low 40mm, meaning that if you centre one of the five
holes in the disc carried over one of the six holes in the wheel,
there is still partial overlap with some of the other holes. I guess
I *could* drill a sixth hole in the carrier (opposite one of the
others) and slot the other four appropriately. Feels a bit crap, tho.

 

This solution has been considered. It'd be a right pain in the arse,
and ultimately cost more money unless I could find 2nd-hand 17" wheels
that would fit, and didn't involve me going through exactly this
rigmarole.

 

Eaton Engineering Disc Carriers?

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Ben

Nope. *Way* too safety critical for a dabbler.

 

I think I'd be worried about the carriers warping with the heat and then
your posh floating discs not floating any more.

Buy new carriers, they can't be that pricey can they?

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Champ

I can't remember, are the carriers made from steel?

I can do the drilling but I'd want the opinion of someone-wot-knows
regarding possible side effects from the heating involved in the
welding. I'm thinking of warping, cracking, or destroying any existing
heat treatment here.

 

Having an overlay ring cut/welded/drilled over an existing carrier would
seem like the safe and easy option for values of easy applicable to
engineering shops.

 

Is there really insuffient metal on the carrier to allow the 5 holes
to be drilled without the weld?

 

Good call. No disrespect to your skills, Nigel, but I don't think
that any of us know how far we can go in this sort of respect.
Well, I wouldn't - and I wouldn't ride the bike fitted with a
re-drilled/slotholed wheel and neither would I allow any of my friends
to. And I've done some well dodgy stuff in my time, too.

 

EBC have quoted 400 quid for a pair of carriers and discs. Twice the
price of standard ones.

 

It's not just money. As well as having quoted 400 quid for a pair of
discs with carriers, EBC also say 12 weeks *minimum*. The season will
be half over by the time I get them.

 

Couldn't you just carry more corner speed?

 

Aren't there any standard discs with the correct spacings you could buy?

 

In short, no. I wouldn't do it and I would not want you or the other
lads to ride the bike with welded carriers. It is way too dangerous.
I can see why you want to do it, but this is not the area to cut
corners. I can explain at great length so you will fully understand
if you like, but I don't have the time right now.

A set of appropriate carriers. Period. Sorry.

Confirmed by email.

 

You might already know but this lot might have what you need.

http://www.sportsbikeworld.co.uk/For Sale/parts_for_sale.htm

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Pip

Heh, wot skillz?

"A man has to know his limitations".

 

Std mounting is 5 hole.

 

Hence cut - welded - drilled.....
I can't think of another trustworthy way to do it. Still a bit of a botch
but probly safe enough.

Do you know what carriers the wheel was originally drilled for.