Rotor Offset problems.....

[scottychop]

Hello,

I thought I'd post this as a separate thread from my build to get some specific advice. I am putting together a GSXR front end using a stock GS450 front wheel. I just discovered that the 93 GSXR caliper is very wide and hits the mag using my stock disks. I am wondering if it's possible to space the rotors out from the stock position using some sort of spacer?? I imagine as long as the spacers were all the same size with little variation things would be ok?

[Agemax]

slightly confused....if your caliper hits the wheel then i take it you are planning to space out the caliper too? a machined steel ring would be ok to space the rotor out, i wouldnt use seperate spacers for each bolt on the rotor

[posplayr]

slightly confused....if your caliper hits the wheel then i take it you are planning to space out the caliper too? a machined steel ring would be ok to space the rotor out, i wouldnt use seperate spacers for each bolt on the rotor

Yea seems a complete ring with bolt holes drilled rather than small rings around each bolt would provide much more support.

Of course if you are spacing a full floating disk it would not matter. Are you using GS450 rotors or GSXR rotors?

[scottychop]

I

I am trying to use the stock wheel and rotor, with the GSXR caliper. I already made a bracket to space the caliper to the correct width and depth of the 450 rotor, but hadn't had them in hand to measure the amount of offset needed. I am about 1/4" to 3/8" off.

Scott

[scottychop]

Like this?

This is kinda the direction I was thinking,

[makenzie71]

been there...done that...do NOT put a spacer behind the rotor. Leave the rotor flush on the wheel and do something different. Unless you're looking at radial calipers, in which case a spacer wouldn't work anyway, you have a ton of 2-piston options that will fit.



(yay I got to post my old CX TWICE today!)

I set that up to use Tokico 6-piston calipers...wouldn't clear the wheel and, turns out, they would have been way overkill anyway.

[GregT]

Been there, done that many times....

A stepped spacer is best - machined to locate on the hub and stepped to locate the disc center.
Given good quality fasteners this method gives no problems.

[Macmatic]

Doesn't the "twinpot" mod use spacers to bring the new rotors out from the hub? Its been a while since I made any measurements myself but I thought that mod used a 5mm spacer to bring the new disk out the same distance from the hub.

/\/\ac

[posplayr]

Doesn't the "twinpot" mod use spacers to bring the new rotors out from the hub? Its been a while since I made any measurements myself but I thought that mod used a 5mm spacer to bring the new disk out the same distance from the hub.

/\/\ac

I think part of the twin pot mod is to use non GS rotors that are larger .

[Macmatic]

I think part of the twin pot mod is to use non GS rotors that are larger .

Right, but I thought they had less offset built in and were spaced out 5mm to make them line up with the caipers. I can't find the details on it but I was under the impression there was a spacer with holes to match the GS hub which could be used to mark and drill the Fireblade rotors. It might have also been stepped to center the rotor on the hub?

By the way, I got a set of those emulators from the Yamaha site today, they look pretty sweet! I think they'll work on my 37mm GS750 forks too but I'll put that in another thread.

/\/\ac

"Doesn't the "twinpot" mod use spacers to bring the new rotors out from the hub?"

[salty_monk]

Yes... I might be able to find you some hub spacers that suit. Some I had were 5mm, some 4mm & I have also had some 3mm & 2mm made up at some time when I was experimenting but I am not 100% what I have left now if anything.

Should be getting some more soon but they are 4mm. I suppose you could use 2 sets.

No problem with putting the full ring behind the rotor that I can see or have experienced.

Dan

[Macmatic]

Yes... I might be able to find you some hub spacers that suit. Some I had were 5mm, some 4mm & I have also had some 3mm & 2mm made up at some time when I was experimenting but I am not 100% what I have left now if anything.

Should be getting some more soon but they are 4mm. I suppose you could use 2 sets.

No problem with putting the full ring behind the rotor that I can see or have experienced.

Dan

Two questions:

Are these just flat spacers or are they stepped to locate the rotors? If not then its fine to locate the rotor with only the bolts?

Is there a thread where these are discussed? I've seen a few posts that allude to them but no details.

/\/\ac

[scottychop]

SaltyMonk...

Any chance you have pics of the spacers you've had made up? I started on some spacers today out of .25" Alu. but that's almost 6.3 mm. When I measured the clearance of the stock caliper it was almost 9.5mm but didn't need to be. 6mm seemed like a happy compromise. I am not looking to locate new rotors, and am wondering about the design you have.

Scott

[salty_monk]

Looks like your flat spacer above. No step Mac but that would be the better way to go (if it didn't increase the cost several times over due to all the extra material that would have to be removed).

As long as the holes are drilled correctly (8mm not 10mm) & you use shoulder bolts of the right spec there should not be any problem.

[jwhelan65]

Just curious, what is the reason or benefit of the gsxr front end over the stock if you are leaving the stock 450 wheel?