Rear caliper mount

[croat1]

JJ’s Machine 86-89 Trx250r rear caliper mount

[Langbolt]

Hey Joe, I reached out to him and suggested he offer a mount like that , that would incorporate the 250R caliper mounting holes....BUT would use a NEWER Nissan caliper from the HONDA CRF Front Caliper. Like the Swap I did years ago....It's a Twin Piston Caliper with no Emergency Brake.....I have not heard back from him.....

Here's the old post for reference

https://www.forums.trx250r.org/index.php/topic,2591.60.html

[croat1]

John, that would be an ideal setup utilizing a dual piston front caliper.

Joe

[Langbolt]

Joe,

This pic shows how close the CRF Caliper mount is to the TRX Support.....it's off by 1/4"

So, either supply a NEW Steel Support....which I have made out of Stainless.

Or supply a NEW Caliper mount to adapt to the TRX support.

[All250R]

Joe,

This pic shows how close the CRF Caliper mount is to the TRX Support.....it's off by 1/4"

So, either supply a NEW Steel Support....which I have made out of Stainless.

Or supply a NEW Caliper mount to adapt to the TRX support.

That is really close, especially if it floats center line with the rotor.
Is the leverage ratio the same as the stock caliper too (calculate piston face area)?

[Langbolt]

Joe,

This pic shows how close the CRF Caliper mount is to the TRX Support.....it's off by 1/4"

So, either supply a NEW Steel Support....which I have made out of Stainless.

Or supply a NEW Caliper mount to adapt to the TRX support.

That is really close, especially if it floats center line with the rotor.
Is the leverage ratio the same as the stock caliper too (calculate piston face area)?

It's so close that HONDA should have made it the same size...

The Caliper Pistons are the same diameter, so I would say the lever ratio is the same....it works really good and it's a very clean look.

[All250R]

Joe,

This pic shows how close the CRF Caliper mount is to the TRX Support.....it's off by 1/4"

So, either supply a NEW Steel Support....which I have made out of Stainless.

Or supply a NEW Caliper mount to adapt to the TRX support.

That is really close, especially if it floats center line with the rotor.
Is the leverage ratio the same as the stock caliper too (calculate piston face area)?

It's so close that HONDA should have made it the same size...

The Caliper Pistons are the same diameter, so I would say the lever ratio is the same....it works really good and it's a very clean look.

I haven't done much with R tech, or riding since we focused on our relocation to ID.
That caliper is still used for 2026 bikes. Have you done anything to make this a kit for people to buy? If the leverage ratio is the same, seems like a great solution, given how many stock pistons and calipers are corrosion damaged by now.

I still need to get my cylinder head prototype dome machined and tested - however, my lathe got damaged in the move. At least I have lots of ground to actively test now.