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Rotor thickness for 88 FZR1000?

Started by FJmonkey, January 22, 2012, 01:02:53 PM

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FJmonkey

Quote from: jvb_ca on January 29, 2012, 09:03:25 PM
Hi Hein. I just checked my Haynes...it says 4mm (3.5mm min) same as my Clymer. My GYSM says same thing for 89-90, and 91-93, 4.0mm with 3.5mm min. My GYSM is a CycleHippie version from Ebay that a fellow member sent me a few years back, so who knows how accurate it is. It appears to be scanned from original hard copy of GYSM. : :scratch_one-s_head:
Hi Arnie. I looked very close but don't see any stamped numbers on rotor.
At least everything seems to agree with the max wear limit of 0.5mm. :good2:
Cheers...Jake

Sounds like we got this bastard by the tail, 89 and up rotors from an FJ with a minimum of 3.5 mm worst case to get me through WCFJR and up to 4 mm giving me more mileage before a new set is required. Feels kind of like falling from the top of a tree and hitting every branch on the way down. Thanks again everyone.
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

Mark Olson

Monkey Mark, 

Don't sweat the thickness of the rotors too much as long as there is no deep scars in them and they are true .  If rotors are wasted they will be warped from the heat so check for run out as you spin the wheel.

Rotors may look good on the surface and be warped to hell.

save up the old front rotors of the 84-86 because they can be used to replace the rear rotor on all year fj's. :mail1:
Mark O.
86 fj1200
sac ca.

                           " Get off your ass and Ride"

FJmonkey

Quote from: Mark Olson on January 30, 2012, 12:38:56 PM
Monkey Mark, 
Don't sweat the thickness of the rotors too much as long as there is no deep scars in them and they are true .  If rotors are wasted they will be warped from the heat so check for run out as you spin the wheel.
Rotors may look good on the surface and be warped to hell.
save up the old front rotors of the 84-86 because they can be used to replace the rear rotor on all year fj's. :mail1:
Sounds good, I just need a set of 89 or up rotors not too far away from 4.5 mm and still straight. I still have all the bits I took off the rear when I did my 92 GSXR upgrade. Not sure if the FJ rotor will swap to the GSXR but I am not worried, I rarely use the rear brake as I spend most of my miles leaned over. The rear should last another 20 years.
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

Arnie

The FJ rear rotor is significantly larger in both diameter and thickness than the GSXR rotor.  It won't fit.

Arnie

FJmonkey

Quote from: Arnie on January 30, 2012, 07:17:36 PM
The FJ rear rotor is significantly larger in both diameter and thickness than the GSXR rotor.  It won't fit.
Arnie
Then it will likely go to a needy FJ owner on a budget. Thanks.
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

Mark Olson

Quote from: FJmonkey on January 30, 2012, 07:13:35 PM
Quote from: Mark Olson on January 30, 2012, 12:38:56 PM
Monkey Mark, 
Don't sweat the thickness of the rotors too much as long as there is no deep scars in them and they are true .  If rotors are wasted they will be warped from the heat so check for run out as you spin the wheel.
Rotors may look good on the surface and be warped to hell.
save up the old front rotors of the 84-86 because they can be used to replace the rear rotor on all year fj's. :mail1:
Sounds good, I just need a set of 89 or up rotors not too far away from 4.5 mm and still straight. I still have all the bits I took off the rear when I did my 92 GSXR upgrade. Not sure if the FJ rotor will swap to the GSXR but I am not worried, I rarely use the rear brake as I spend most of my miles leaned over. The rear should last another 20 years.

forgot you had the gsxr rear wheel .

If you have the fzr you can use the front rotor on the rear.
Mark O.
86 fj1200
sac ca.

                           " Get off your ass and Ride"

FJmonkey

Quote from: Mark Olson on January 31, 2012, 12:23:37 PM
forgot you had the gsxr rear wheel .
If you have the fzr you can use the front rotor on the rear.

Excellent, that means I have a 300 year supply of rear brake rotors, The one on it now is likely good for 100, and the other two fronts another 100 a piece. I am gonna take that off my shopping list now... :rofl2:
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

Dads_FJ

forgot you had the gsxr rear wheel .

If you have the fzr you can use the front rotor on the rear.
[/quote]

The FZR rear rotor on my bike is drilled... so if it is interchangable with the FJ 16" front rotors... does this imply that someone using a 16" front wheel can replace the front rotors with FZR rear drilled units?  That'd be cool...
John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20

FJmonkey

Quote from: Dads_FJ on January 31, 2012, 09:13:15 PM
forgot you had the gsxr rear wheel .
If you have the fzr you can use the front rotor on the rear.
The FZR rear rotor on my bike is drilled... so if it is interchangable with the FJ 16" front rotors... does this imply that someone using a 16" front wheel can replace the front rotors with FZR rear drilled units?  That'd be cool...
[/quote]
The rotors are too large in diameter I think to use for stock FJ. I think he was referring to using the FZR front rotor on my GSXR rear as a spare.
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

Mark Olson

whoa hold up.

the stock rear rotor of a fj is reused in the fzr rear wheel mod . the stock fzr rear rotor will not work on a fj front or rear.

The front rotors of a 84-87 fj are the same as the rear rotor of all years fj.   soooo if you mod a fzr wheel to the rear of your fj you can reuse the stock rear rotor on it and after you change out the front wheel to a 17" you will have two spare rotors left over for the rear wheel.

I hope that clears it up.
Mark O.
86 fj1200
sac ca.

                           " Get off your ass and Ride"

Dads_FJ

Quote from: Mark Olson on February 01, 2012, 11:44:33 AM
whoa hold up.

the stock rear rotor of a fj is reused in the fzr rear wheel mod . the stock fzr rear rotor will not work on a fj front or rear.

The front rotors of a 84-87 fj are the same as the rear rotor of all years fj.   soooo if you mod a fzr wheel to the rear of your fj you can reuse the stock rear rotor on it and after you change out the front wheel to a 17" you will have two spare rotors left over for the rear wheel.

I hope that clears it up.

ya, clear as mud!  I thought I had the FZR rotor and caliper on my '84 with the 17" upgrade, now I have to check when I get home.
John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20

Dads_FJ

Quote from: Dads_FJ on February 01, 2012, 12:02:07 PM
Quote from: Mark Olson on February 01, 2012, 11:44:33 AM
whoa hold up.

the stock rear rotor of a fj is reused in the fzr rear wheel mod . the stock fzr rear rotor will not work on a fj front or rear.

The front rotors of a 84-87 fj are the same as the rear rotor of all years fj.   soooo if you mod a fzr wheel to the rear of your fj you can reuse the stock rear rotor on it and after you change out the front wheel to a 17" you will have two spare rotors left over for the rear wheel.

I hope that clears it up.

ya, clear as mud!  I thought I had the FZR rotor and caliper on my '84 with the 17" upgrade, now I have to check when I get home.

I'm sure this is the rotor which came with the FZR wheel (I never had drilled rotors on the front).    Unless... you are saying that I should not be using it for some other reason.


John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20

Mark Olson

Quote from: Dads_FJ on February 01, 2012, 01:01:34 PM
Quote from: Dads_FJ on February 01, 2012, 12:02:07 PM
Quote from: Mark Olson on February 01, 2012, 11:44:33 AM
whoa hold up.

the stock rear rotor of a fj is reused in the fzr rear wheel mod . the stock fzr rear rotor will not work on a fj front or rear.

The front rotors of a 84-87 fj are the same as the rear rotor of all years fj.   soooo if you mod a fzr wheel to the rear of your fj you can reuse the stock rear rotor on it and after you change out the front wheel to a 17" you will have two spare rotors left over for the rear wheel.

I hope that clears it up.

ya, clear as mud!  I thought I had the FZR rotor and caliper on my '84 with the 17" upgrade, now I have to check when I get home.

I'm sure this is the rotor which came with the FZR wheel (I never had drilled rotors on the front).    Unless... you are saying that I should not be using it for some other reason.





how thick is the rotor ?  stock is .300"   .
it looks like that is the stock rear brake caliper , is that correct?
Mark O.
86 fj1200
sac ca.

                           " Get off your ass and Ride"

Dads_FJ

I'll have to mike the rotor to see how thick it is.  I did the mod a looong tome ago and I should have documented everything, but didn't - the caliper is silver so I believe it's from the FZR. 
John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20

Dads_FJ

Here's what I have, rotor measures 4mm. 

John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20