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MARTIN KELSON
06-01-14, 08:23 PM
Has anybody any experience of machining wheel hub face to alter offset?
Acquired some new wheels & after measuring offset I think there a 45mm & not a 49mm as sold to me so thinking if I can find somewhere if I can machine 4mm of the mounting face?

only other idea was thinking of changing to ally bells on the front brake so maybe have a different bell offset to move wheel inward, but then what do I do with the back?

Any thoughts or ideas appreciated.

ASH GSI
06-01-14, 08:45 PM
you think they are 45mm? it should say ET then a number on the wheel. I had a few mm taken off of a wheel hub years ago, it depends how much metal is there as to if it can be done or not, I think that you can go to around 4 or 5mm after the head of the bolt/nut if that makes sense. a local wheel refurb place did it for £20 cash but that was over 10 years ago. I didn't have any problems with that wheel after.

Novasport
06-01-14, 09:25 PM
I thought you had your old grey twin spoke Speedlines machined to fit. A 45mm offset is perfectly OK if you have the clearance. My Irmscher Spokes are 6x15" with ET42 and are fine.

MARTIN KELSON
06-01-14, 10:39 PM
No markings on the inside of the wheel for offset. I only 'think' there et45 by searching the net on how to calculate offset so as long as I've done it right then they are et45.

Yes my Speedlines were machined buy by Speedline themselves. Called them today & don't have facility to machine now.
45mm offset will probably be ok, I just if I can wanted them right!!

Novasport
06-01-14, 11:06 PM
Offset is dead easy to calculate. Measure the overall width of the wheel from outer rim to inner rim to get measurement A. Place the wheel face down and put a straight edge or plank of wood accross the back of the rim. Measure from the wood to the mounting face to get measurement B. Divide measurement A in two and deduct it from B to get your offset.

ie...

A = 150mm. So A divided by two = 75mm.

B = 124mm

124mm - 75mm = ET49mm

Benn
07-01-14, 09:37 AM
It's an easy job for a good machinist. Can be done on a mill or a lathe with only a bit of set up time. I've been looking in to it alot. Due to fancying wheels that dont fit.

Get a rim to a engineering shop they'll be able to tel you how much they can take off and it be safe and strong.

SimonTW
07-01-14, 09:37 AM
http://www.tttoolsltd.co.uk/services/-offset-et-of-wheels-increased-or-reduced

Benn
07-01-14, 09:39 AM
Ooo a very very handy place^

Altho.


There are two main offsets Positive and negative, We can create both, either Increasing or reducing the offset using our CNC Machines.

You cant reduce off sets by taking metal off, you have to add it.

MARTIN KELSON
07-01-14, 05:34 PM
http://www.tttoolsltd.co.uk/services/-offset-et-of-wheels-increased-or-reduced

did come across this place whilst searching the net, sadly nowhere near me.

Have just popped into a machine shop by where I pass on the way home, done wheels before & happily machine 4-5mm to give me the required offset & £80-100 for a set so not too bad.
will have a measure up & see what I want to do.

GRUNT 16V
09-01-14, 03:12 PM
What is the width (j) of the wheel itself ?? You have to go careful not to take off to much as you may get issues rubbing on the shock absorber !!

MARTIN KELSON
09-01-14, 06:34 PM
They are 6.5 x 16
just getting them machined to a proper 49mm offset & there only few mil out so hopefully no issue with shock rubbing.

Benn
10-01-14, 11:04 AM
Sounds like your all sorted. Just need to pick a colour now ;)

scott.parker
10-01-14, 02:38 PM
What wheels?? ;)

Nick J
11-01-14, 03:09 PM
What wheels?? ;)

;)

Pistol Pete
11-01-14, 03:24 PM
What wheels?? ;)

What he said