Since the price of TRX parts are on the rise I find it beneficial to all to find parts that are not only a cost effective replacement but also OEM Honda.
Here I'll be installing a CRF front brake master cylinder.
Any year CRF250/450 can be used.
The body of the cylinder is smaller than the stock TRX and will clean up the handle bars nicely. These are easily found used in great condition on eBay or group pages on Facebook.
Let's get to it.
Top is a CRF. Bottom is TRX. Notice the TRX has a much thicker mount for the handle bars. This thicker mount is so the master will clear the throttle.
Here is a picture of the CRF master on the bars. Notice the master is touching the throttle. Also the brake line is touching the bars. Clearance needs to be made to properly mount the CFR master.
But how you ask? The solution is simple.
You'll need a spacer like this:
You can purchase this spacer at one of two places.
(Mike's custom machine link)
or
(eBay dick head)https://www.ebay.com/itm/274438804438
I personally would purchase from Mike. His customer service is great and he is so easy to work with. My spacer came from Mike. I'll give him a good plug at the end of this post.
Notice now with the spacer installed the CRF master (bottom) now has the same mounting distance as the TRX master (top).
And here she is all installed. Clearance is good next to the throttle and the brake line clears as well.