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Discussion Starter #1
So, I got a really good deal on a set of PVM wheels for a 2012 R from a buddy of mine who use to be a Dealer. Fitting the rear is no big deal, gonna do the axle swap, blah blah blah.
My question is about the front. I have the bearings, seals and axle spacers sorted but the brake rotors don’t quite hit center of the calipers. There is about a 2 to 3 millimeter difference between the two. My existing rotors look to have a 12mm offset. So I Googled 5 bolt 15mm offset brake rotors and it came back with rotors for a Ducati 749. Has anyone done this successfully? I know I can get custom rotors but that is a bit pricey and I would prefer to stick with off the shelf parts preferably Triumph or Ducati if it works.
Thanks in advance.
 

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Discussion Starter #2 (Edited)
Damn...Tough crowd...
How about this. Is the retaining ring necessary since the three spacers seem to lock the bearings in place?
 

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Damn...Tough crowd...
How about this. Is the retaining ring necessary since the three spacers seem to lock the bearings in place?
How about this...been looking for a set of PVMs for my '14 S3R, if you can't make them fit ring me up and I'll take them off your hands...:)
 

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Discussion Starter #4
Heyyy, there is life out there. Absolutely, in the meantime got any suggestions to make ‘em fit my bike cause we already know they fit yours.😁
 

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...the brake rotors don’t quite hit center of the calipers. There is about a 2 to 3 millimeter difference between the two. My existing rotors look to have a 12mm offset. So I Googled 5 bolt 15mm offset brake rotors and it came back with rotors for a Ducati 749...
Are you saying the discs need to be further away from the wheel centreline or closer to it? If the former then you could put washers between the disc and wheel to make up the difference.

Otherwise I would contact a brake disc manufacturer to confirm if the pitch circle diameter for the Ducati mounting bolts is the same as for your wheel.

I assume you've checked the discs from 2011+ Speeds don't sort the problem?
 

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I had a similar situation when I fitted the Brembo equipped fork assembly from a 2009 S3 to my originally Nissin equipped 2006 S3. Fortunately my local wrecker let me rummage through his pile of Triumph discs until I found some with the offset I needed. I ended up with a set from a 2005 Sprint ST. It's important to know the correct way to measure when determining offset so you might find the attached diagram of use.
brake-disc-offset-measure-mm.jpg
 

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I've been doing some digging for something else and found the Galfer online shop gives all the specs for a disk including offset and mounting pitch circle diameter. Hope that helps.
 

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Discussion Starter #10
Hey, thanks for the responses.

Rampant, the rotors need to be further apart. I’ve heard a little bit about using washers to space them out and I can order ring shims as well as have a single piece shim fabricated but I was a little worried about the sheer load introduced on the rotor bolts. I’m probably overthinking it, 1.5 to 2mm probably isn’t enough to overload the bolts. Have you done this and was the bike used in heavy braking applications like track days or racing? Also, thanks for the heads up about the Galfer website. The 2012+ rotors from an R with PVM wheels has the same offset and bolt up to the 2005 wheel and vice versa. So if anyone is looking to upgrade their rotors 👍.

Terry, that is pretty close to what I’m trying to accomplish. I had a 2009 donor bike that I have grafted parts from. Didn’t care to much for the blacked out front end and I wanted to use R1 calipers with the 05 wheels. But, having come across ‘12 wheels I can overlook the color (first world problems)😁. Anyway, I’m having a hard time understanding why I keep reading the brake rotor offset is measured from the mounting face of the carrier to the outside of the rotor. Most applications (eg.pipe, handrails etc.) are measured from center to center (mounting face to inside of rotor), including. ISR’s form for custom brake rotor fabrication. Is this just against the norm?
 

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.......... I keep reading the brake rotor offset is measured from the mounting face of the carrier to the outside of the rotor.
Which is as per the diagram I posted and the way I understand most in the motorcycle business would do it.

.........Most applications (eg.pipe, handrails etc.) are measured from center to center.......
Yes, I agree. Having spent most of my life in industrial engineering, centre to centre dimensions are the norm especially where rotating plant is involved. The last few years though have introduced me to drafting services out of places like India and they will flout engineering conventions if you're not careful. Can make for some expensive mistakes so you have to be immune to criticism when insisting on compliance.

.........including. ISR’s form for custom brake rotor fabrication. Is this just against the norm?
Not sure who ISR are but if they measure it that way I'm not in a position to say it's wrong. I only posted the illustration so you had a common basis on which to base your comparisons.
 

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Rampant, the rotors need to be further apart. I’ve heard a little bit about using washers to space them out and I can order ring shims as well as have a single piece shim fabricated but I was a little worried about the sheer load introduced on the rotor bolts. I’m probably overthinking it, 1.5 to 2mm probably isn’t enough to overload the bolts.
Cool I thought so but wanted to check.

I agree you're overthinking it, people space out their rotors all the time when doing front end swaps. I know for a fact that D'Ecosse has been running his front rotors spaced out 1.5mm for at least 10 years, see his GSXR front end swap thread in his signature. He initially used washers then had a ring shim fabricated.

If you go the washers route, make sure you measure them all with a decent set of calipers or micrometer to make sure they're all as close to the right size as possible. If they're all over the tolerance band you may give your disc a slight runout. I'm probably overegging it but brakes are important :)
 

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010509Speedy, I've a set of perfectly good stock discs from a 2006 1050 Speed Triple (the 2005-early 2007 model). They are the ones with gold carriers, are straight and true, have done very little work (less than 20000kms and are sitting in a corner of my garage. They have an offset of 18mm measured in accordance with the illustration I posted. They're on ebay if you follow the attached link. Freight between USA and Australia is usually pretty expensive but the exchange rate between our currencies is so whack ATM it might be worthwhile. If they are of interest let me know.

 

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Discussion Starter #15
You guys are awesome, thanks so much for the advice and information.

Rampant, I remember Decosse mentioning the shims in another thread somewhere and I searched trying to find more info on them, didn’t even think about the thread he has for the front end swap on his bike. The shims I’m thinking of using say they have a tolerance of + or - .14 to .21mm. I will double check with a set of calipers.

Terry, thank you for the offer on the rotors but I have 05 rotors on my bike currently and when I measure as you describe they are also the same 18mm offset. I’m glad you cleared that up for me because obviously the Ducati rotors wouldn’t have worked being only 15mm.

One final question though, do you all think I will need the c-clip that holds the bearing in place on one side? I’m thinking, I won’t need it because once everything is assembled the three spacers, shoulder on the axle and the left side fork leg will hold everything in place.
The reason I want to delete it is because the original bearings in the ‘12 wheel are 14mm thick and the bearings I’m going to use are 12mm thick.
 
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