Hmmmmmmm...... Got some FZR 1000 rotors......

[Country Joe]

......does anybody have 320 mm rotors mounted up on FJ forks? What I'm wondering about is the availability of adaptors to mount the calipers farther away from the fork legs to be able to run the larger rotors.  I will take some measurements to see if it jis even feasible.  Just thinking out loud..........

[aviationfred]

I know this has been covered before. 

I believe the 320mm FZR1000/FZR750R rotors are too large in diameter. The commonly used Arashi wave rotors are 300mm and fit perfect.

When I bought my FZR750R front wheel, it came with rotors. I didn't even check to see if they fit because I had read on here that they will not fit with OEM forks.

Fred

[airheadPete]

Hmmmm... If you want an idea, go to KLR650.net. There, this has been covered before, (a lot). It's a common conversion for better braking performance, there are drawings of a caliper relocation bracket that might give you some ideas. (Look under the $21 dollar brake/performance mod.)

[oldktmdude]

......does anybody have 320 mm rotors mounted up on FJ forks? What I'm wondering about is the availability of adaptors to mount the calipers farther away from the fork legs to be able to run the larger rotors.  I will take some measurements to see if it jis even feasible.  Just thinking out loud..........

Joe, I'm using the FZR1000 rotors but I have '90 FZR forks. The 320mm rotors are absolutely fantastic, so my suggestion is to do anything that makes using 320's possible. Having said that, I personally don't know of any way of easily mounting them.  Regards, Pete.   
                                                                                                                                                 

[Alf]

Take a look to my web, "suspension" at the menu. Its possible fitting 320 rotors and keeping the geometry with a mix of FJ and FZR parts. The work is in progress... well, I´m only waiting for completeing the day that any of the fork oil seal fail

[Country Joe]

Thanks for the feedback, it looks like there are a couple of ways going about fitting the 320 mm  rotors.  I think I will try drawing up some aluminum adaptors and try getting some whittled out.

Joe

[hein]

Joe.

As mentioed by Pete the 320 mm. discs are an upgrade worth doing. I've got a FZ1 with monoblocks along with 320 mm. rotors and in this case size does matter.

It boils down to a question of cost based on resources. I'm assuming the FZR discs have the same offset that the FJ discs have. I don't know this but this important. I've made a number of adaptors for odd brake and calipers combinations over the years and the one major tool you will need is a milling machine. If you don't but are prepared to pay maching costs its not difficult. Should you pursue this I would be happy to give you my insight. Before you dive into this think about how much money your prepared to spend. This is not a vice, hacksaw and diegrinder project.

In maching setup time is often more then cutting time.

Hein.

[Country Joe]

hein,
I appreciate any and all input on my projects. For a little background on me, I was a machinist for the first 14  years of my wage earning years, started out before that with 2 years of machinist training in our local vo-tech school. I started out as a button pusher running Cincinnati Milacron tape reader NC milling machines at my first job and finished my machinist career building  fixtures and tooling in a aircraft repair facility that specializes in thermal spray repair of aircraft and industrial parts. So I don't think it's bragging to say  that I could make these adaptors in my sleep. Happily, I have a retired neighbor that has a Bridgeport mill  and a  small Clausing lathe in his shop.  All I have to do to get to use his machines is to give him some lessons on properly using them. Pretty good deal to me, I may have to buy a few cutting tools, I don't know how well he
is set up in that regard.
So no worries about me trying to whittle something out with a file.

[jscgdunn]

Joe that is a dangerous background for someone with moditis

Jeff   envy

[Country Joe]

You're telling me! I even have a few blocks of titanium scrap that would be big enough to make the adapters. I've been lugging them around the country since 1989. I made some windshield brackets out of the stuff for a 1986 Radian. Talk about overkill, aluminum would have been fine, but not nearly as cool as titanium.

[hein]

Hi Joe.

  Seems like you've got the qualifications and the tools to do the job so I won't bore you with my thoughts on how I'd make the adaptors. The only thought I'll pass on is in reference to the disc offset. A few years back I made some adaptors for larger dia. rotors and different calipers for a project bike. The original rotors had positive offset but the new ones were straight thus moving the calipers inboard from the original location and obviously further out relative to the axle centerline. I was using the bare caliper, no pads, and everything lined up as intended. Installation with pads in the caliper proved to be impossible however. Options where either going to offset discs, or making spacers to offset the discs I had, which in both cases meant making two new adaptors. I took the easy way out and ended up installing the calipers first and then slipping in the pads. This meant dropping the pads out first before the calipers could be removed in order to do a wheel removal. Not a huge problem but still a pain in the ass.

  I too started out in metal fabrication and machining for the first 10 yr. of my working life. Switched over to motorcycles in the late 70's but always kept myself involved with machining which is a very handy skill in my trade. Never got to use cnc equipment, the dro on my milling machine is most modern thing I own.

Hein.