F2 Conversion-Front End
by Brian McCoy

Ok, so you've picked up the following from a CBR F2 or F3:
  • Front wheel with bearings, rotors, spacers and speedo drive (F2 only)
  • Axle and retaining nut
  • Forks with axle clamp bolts and caliper retaining bolts
  • Calipers with brake pads
  • Front fender
  • Triple trees with all mounting hardware (4 bolts)
  • clip-ons with bar ends

You'll also need the following from your VFR or new:

  • VFR lower triple (for the steering stem)
  • Steering bearings (you can use OEM ball, or taper - the OEM balls give a lighter feel)
  • All switch-gear and master cylinders (this can be switched out if you want, but it takes
  • some redesign)

First things first... do NOT do this conversion unless you have installed heavier fork springs in your forks. Your VFR will become downright DANGEROUS without these heavier springs. My starting point on the forks was 1kg springs, 10wt oil and Gold Valve Emulators on 4 turns - I'm also a 230lb guy who rides very aggressively). Hopefully you have a manual with you for assistance on braking down the VFR. Basically, you're going to need to remove the lowers and upper fairings. Remove the front wheel, remove the fender, and remove the forks from the triples. Pull the top triple, then slide out the bottom (watch those bearings, they get into the oddest places). You'll then want to remove the brake line from the master cylinder. So, your bike's been stripped down.

Time to have a machine shop press the stem from your VFR lower triple out, and insert it
into the CBR lower. If the shop doesn’t frequently work on motorcycles, make sure they know to press the steering stem out _through_the_bottom_ of the lower triple to remove it. They with have to lathe the diameter to match the F2 stem. Mine's tack welded just for some extra security. The steering stops will also need to be machined down a little bit (use the VFR for a guide). You'll need to tap out the bearing races from your VFR headstock at some-point (NEVER reuse races - that's asking for trouble later). Remove all the switch-gear and controls from your VFR bars, and install them on the F2 bars (you can use 90+VFR bars as-well, for a little more rise - that was uncomfortable for my 6'4" frame though it might work well for shorter people). You should also set up the lines for your new F2/F3 brakes and bleed them (make sure you stick something in-between the pads when you bleed them). Don't forget the ignition set like me... :)

Now for installing everything… You’ll need to insert and seat the new bearing races into the headstock first. I usually cool the races in the freezer (yeah, wives and roommates sometimes complain about the motorcycle bits in the house. This makes them a tiny bit easier to insert. PVC pipe again comes in handy to pound the bearings home. Once those are installed, clean the area REALLY well. Just douse everything with cleaner, and wipe it clean - you don’t want any dirt or grim in the bearing area. Pack your new bearings with grease, and slide the stem up and into the headstock.. fitting the packed upper bearing over the stem, and the 2 spanner nuts. Honda recommends torquing the new bearings to a certain spec first, then loosening and retightening – pay attention to this. If you don’t follow their directions, you’ll find the bearing slowly setting in over time, which means they’ll go from tight to loose every few hundred miles, and you’ll need to re-torque them over and over again… not only is it a pain in the ass, it causes sloppy handling, and could damage the bearings. Okay, now that you have the lower tree installed, slide the top triple and secure it loosely. Next, slide the fork-tubes up into the triples, and secure the clamp on the bottom triple. Personally, my forks are set at a height were you can just see the groove where the retaining clip (that I’m missing) should go. It’s a good starting spot. Install the other fork and secure in the same fashion. Next, put the axle in, and visually align the forks. If you want to check for straightness, I’d suggest getting a small piece of plate-glass that you can rest across as much of the fork tube (not the lowers) as possible and check for any raised edges. (Glass is used because it’s the most commonly available item that will be perfectly flat). Once you have the forks lined up, go ahead and tighten the rest of the pinch-bolts and torque them to spec. Time to check how tight you have the bearings.. and adjust to your desired level. I use a fish scale (like, to weigh small fish?) attached to one clip-on at the end and see how much actual force it takes to turn the front (the front has to be elevated, and this won’t work on a stand a Pit-Bull stand or any other that holds the bike by the forks or steering stem). Most people like between 3 and 5lbs, I have mine set at 6lbs.. it’s a bit harder to turn in around town, but I like the feel once rolling down the road. This is adjusted by the lowest spanner nut (and alternately changes the torque setting on the steering stem bearings). Now, it’s just a matter of reassembling the bike.. put the clip-ons back on the forks, put the fender on the forks, install the front wheel, and replace your bodywork up front.

Check to make sure all your bolts are secure.. that the brakes work, and your clip-ons are tightened down.. It’s a rather simple job, but be careful on your maiden voyage.. we all are human and may forget something important. Anyway, you’re done.. go out and enjoy the ride!

-Brian McCoy


Disclaimer: This information has been been reviewed and, where possible, verified. We are not, however, responsible for any mistakes or omissions that have slipped past us. When in doubt, seek official verification.


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