Fitting an '05 cbr600rr front-end onto an '03....

Will this work? Do you know anyone who's done it, or tried to?  

If you don't get any answers on this, you can try to find out yourself with some research. Go to the Honda dealer and find out if the steering head bearings and races are the same part number. If not, then you'll need to find a way to get measurements on those parts to see if they're adaptable in some way.  

I've been curious about this myself. I am going to check out the parts and see if Max at Traxxion Dynamics has worked on any yet to get a little more insight on the geometry differences.  

I'd take the money and revalve/spring your '03 front end.  

Revalving the stock 03 forks will only make it more adjustable and smoother. The 05 front end are inverted with radial calipers "much better braking". Revalving the 03 forks will make it more stable under braking but the 05 will brake much better. If he's going to get the 05 front end then he should replace the stock master cylinder because it's not a radial master.  

A bit hard to judge no? Who is to say that the more controlled suspension won't yield shorter stopping distances in many cases? The '03 brakes are plenty powerful I'm sure.  

The cbr is a very stable bike from the start so I don't beleive revlalving the front will out perform a completely better brake system, just my opinion.  

I actually have a re-valved and re-sprung racing front end including a nissin radial master for the front brakes [why won't honda do this stock?]. It is not a question of the performance of the forks themselves but a question of the amount of flex in the system as a whole. In real world terms I don't think radial mounted calapers do squat for breaking performance. The feel of a stock system may be better with radial mounts but some very basic mods quickly close that gap. To me the real benefit of an upside down fork is that the fork attaches using the thickest and stiffest part of the fork tube and therefore flexes less as it is loaded. This reduces stiction and bending in the fork tubes which makes the suspensions behavior more predictable. Under heavy loading conditions the UD forks should remain more consistent.  

While every bike will act differently under braking conditions and I've ridden three different cbr600's all three brake very well. However, I have an 03zx6rr with radial mounted calipers and I can out brake them at the track with very little effort.

Honda didn't change their forks and brakes for 05 for no reason they did it because it's a better braking package.

You don't see many people racing professionally with standard forks and brakes they use inverted forks with radial calipers and master cylinders.  

I worked with break tech for quite a while when considering where to spend my racing budget. After a great deal of research I can promise you that a radial mount for your calipers makes very little difference to the real world performance of the braking system overall. What it does do is allow the calipers to be lighter due to a reduced need to combat the torsion inherent in a perpendicular mount. It also means that the chances of misalignment of the caliper are reduced. That means that ultimately you could experience longer pad life. It has no discernable effect on the stopping power or feel of the brakes. That has more to do with improved technology in the master cylinder, lines and caliper internals rather than with the way they are mounted. The primary reason for the radial mount is weight savings. The primary reason for an upside down fork is improved suspension. The mounting of the brake calipers is secondary to the overall design of the system. That is why with a master cylinder, brake line and pad change I am able to equal or surpass the braking capabilities of a new bike. I want the UD fork for different reasons.  

And if you notice in an earlier post I had suggested that if he was to change to the 05 inverted fork that he also replace the master cylinder. With that package it will brake better.