Here's yet another question for the expierinced MBers



FurryOnTheInside

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Sep 23, 2013
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This is a majority of the email.
For use when attaching a DISC Drive Sprocket
and a DISC Brake Rotor.
3/8 offset (3/4 inch total thickness)
1/4 offset (5/8 inch total thickness)
1/8 offset (1/2 inch total thickness)
Chose your offset,
It's obviously impossible for them to know the thickness of your sprocket unless it comes with a sprocket included.
I am going to suppose this is the offset of the adapter only. That means you have to add the thickness of your sprocket (including any + or - dish if you change it) to this figure because you're bolting it's left side to the right side of the adapter.

If your sprocket happens to be 3/8" thick (including any+ or - dish if you change it) then the figure in brackets is the actual difference in the sprocket position.
 
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FurryOnTheInside

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9 outer holes are 10mm diameter.
This means they use six of the nine holes in your sprocket. But are the holes in your sprocket 10mm diameter? You can open them up. It isn't a problem. But

You might also want to ask them about the BCD. BCD is Bolt Circle Diameter. Are the nine holes in your sprocket centred on the correct diameter to line up with the 10mm holes in the top hat adapter?
Im not saying they are different but you might as well know for sure.
I'm sure they would prefer you buy a new sprocket from them too and they should have lots of tempting sizes to buy and experiment with! :D The prices for MB sprockets are generally speaking pretty cheap.
But you probably want to know beforehand if your kit sprocket is completely compatible, adaptable or not practically very compatible at all.
BCD is important. If holes are just slightly different BCD then drilling to open them out is just about impossible, and filing out the holes and opening them up a bit, accurately, might just be too much PITA for you. I'm sure it could be done, it's just whether you want to know that you have to!
 

FurryOnTheInside

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To check whether the rotor will still fit so you can have disc brakes:
Reinstall the brake rotor on the wheel and reinstall the wheel on your bike.
Measure the clearance between the edge of the rotor and the rear stays of your frame.
The top hat adapter is 3/8" thick material so you need to measure at least 10mm clearance.
 

Frankenstein

In memory of Frankenstein 1991 - 2018
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This means they use six of the nine holes in your sprocket. But are the holes in your sprocket 10mm diameter? You can open them up. It isn't a problem. But

You might also want to ask them about the BCD. BCD is Bolt Circle Diameter. Are the nine holes in your sprocket centred on the correct diameter to line up with the 10mm holes in the top hat adapter?
Im not saying they are different but you might as well know for sure.
I'm sure they would prefer you buy a new sprocket from them too and they should have lots of tempting sizes to buy and experiment with! :D The prices for MB sprockets are generally speaking pretty cheap.
But you probably want to know beforehand if your kit sprocket is completely compatible, adaptable or not practically very compatible at all.
BCD is important. If holes are just slightly different BCD then drilling to open them out is just about impossible, and filing out the holes and opening them up a bit, accurately, might just be too much PITA for you. I'm sure it could be done, it's just whether you want to know that you have to!
10mm doesn't seem right, those holes use a 6mm bolt that has a 10mm wrench head and the holes will take a quarter inch bolt as well which is what I usually upgrade the rag joint bolts to.

If that adapter has 10mm holes what are they expecting you to use to bolt it down? And what sprocket do they want you to use lol..
 

FurryOnTheInside

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Sep 23, 2013
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10mm doesn't seem right, those holes use a 6mm bolt that has a 10mm wrench head and the holes will take a quarter inch bolt as well which is what I usually upgrade the rag joint bolts to.

If that adapter has 10mm holes what are they expecting you to use to bolt it down? And what sprocket do they want you to use lol..
They expect you to use the six 10mm hollow (looks like stainless steel or chromed cro-moly) bicycle chainring bolts provided with the adapter.
They want you to buy their sprockets.
Which is not really too bad since you will no doubt want to try out some of the different sizes anyway.
 

Frankenstein

In memory of Frankenstein 1991 - 2018
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Oh I see now, didn't notice that at first. Kind of OD to use such a large bolt but I suppose it will stand the test of time.
 
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