Yes, every 04-06 R1 part in the frontend is compatible.

From what I can remember, the only difference between 04-05 and 06 is the 06 has a longer swingarm.

 

As Kevin said, the outward stuff is all the same. There was a change in oil level in the 06 and some minor part differences which indicate to me that a valving revision took place (really not a major deal at all). All the parts will bolt up.

Why change from the FZ1 forks, if you don't mind my asking?

 

better forks.

the standard forks on the fz1 are not worth rebuilding due to the way there ware out the outer tubing.

installing a R1 front end on the fz1 lowers and adjust the rake so it improves handling in the corners.

yes could drop the cash (maybe even less) in rebuilding my stock forks. but why not invest in a very solid improvement in the first place.

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Overall weight is similar since the bikes are based on some of the same stuff, so I guess it would work out in the long run. Wasn't aware of a wear problem on the outer tubing.

Good luck with the swap! :thumbup

 

here is a link to a fz group in england this guy did a ton of research on this subject.
yes copyrighted so just a link to his work.

http://fazer1000.yuku.com/topic/3408

there has been a couple others that have used his thoughts and did other was of getting it done.

if i can find the writeup on it it shows how in just 20-30K miles ones forks can be totaled out from use. (NOT repairable).

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