Cbr600f4i rear master

Recently I changed my oem rear master with a cbr600f4i rear master on my 98 vfr. I used the internals of the vfr, onto the cbr shell. And the vfr res. Using a new seal kit from all balls.

The bike has hel delink, the rear locked on after 30 minutes. I rebuild the caliper New lines,.New pads,  new rotor. Bled it all.

And today I rode and 30 minutes the pedal went rock hard so.i stopped, rotor was very hot. 

What am i doing wrong, somebody is saying to.make sure the piston is allowing the compensate valve to put fluid back into the res when it gets hot.

[image: IMG_20221104_174144_109.jpg]

Where did you read to swap the internals?  Put CBR parts back in the CBR unit.

Maybe I'm missing something, but I thought the whole idea is that they are different diameter Masters, and CBR unit gives you some pedal feel back.

Perhaps you need to shorten the CBR threaded section for clearance and/or pedal height adjustment.

Idk...   just going off what I have read over the years.  Somebody else will come along.

5 hours ago, StormShadow3

Recently I changed my oem rear master with a cbr600f4i rear master on my 98 vfr. I used the internals of the vfr, onto the cbr shell. And the vfr res. Using a new seal kit from all balls.

The bike has hel delink, the rear locked on after 30 minutes. I rebuild the caliper New lines,.New pads,  new rotor. Bled it all.

And today I rode and 30 minutes the pedal went rock hard so.i stopped, rotor was very hot. 

What am i doing wrong, somebody is saying to.make sure the piston is allowing the compensate valve to put fluid back into the res when it gets hot.

[image: IMG_20221104_174144_109.jpg]

I agree with the Captain. There are some critical dimensions between the brake pushrod (which locates the piston) and the master housing and its ports, and assuming the ports are clean then your lock up may be due to fluid being unable to escape after applying the brake.

I used an unopened CBR600F4i rear master when I delinked my last VFR and did as Mike suggests and cut some length off the threaded rod to get the VFR pedal in the right location for my big feet.

2 hours ago, Terry

I agree with the Captain. There are some critical dimensions between the brake pushrod (which locates the piston) and the master housing and its ports, and assuming the ports are clean then your lock up may be due to fluid being unable to escape after applying the brake.

I used an unopened CBR600F4i rear master when I delinked my last VFR and did as Mike suggests and cut some length off the threaded rod to get the VFR pedal in the right location for my big feet.

So your using the f4i push rod cut down?, none of the vfr parts

I did the same....used a new RC51 rear master and hacksawed the threaded rod down to length.....

10 hours ago, mello dude

I did the same....used a new RC51 rear master and hacksawed the threaded rod down to length.....

Being shorter it does it still engage all the way

The threaded rod just moves the resting position of the pedal. I found the pedal sat much too high for comfort with the original length of the CBR600F4 master, even with the clevis adjusted to the minimum where the end of the rod starts bottoming out and can go no further. Once I shortened it, it was fine.  

StormShadow3, 11/5/2022 at 5:50 AM

Being shorter it does it still engage all the way

I believe I just shortened it to OEM length, it functions normally....