F2/F3 fork gurus

Discussion in 'WERA Vintage' started by DonDDR, Aug 30, 2019.

  1. DonDDR

    DonDDR Well-Known Member

    At some point years ago, I thot I had figured out I could put F3 sliders on F2 tubes. Bigger brakes. Now that I am looking back into this, I dunno if that is possible. Anyone done this? I havent had my F2 out in a long time and it seems all the parts are dried up. I want to put the F3 front stuff on but not for 700 bux to do it. I have the sliders and calipers, just need a wheel and new springs if I can make it work. Well and bushings etc. Any help is much apperciated.

    Thanks.
     
  2. peterleduc

    peterleduc Active Member

    There is a major difference between F2 forks and F3 and that is the “invention” of the cartridge dampening internally. The chrome tube is likely the same between both models as well as the outer leg and brake calipers. I could totally be wrong on the brakes but I know the are both the same fork leg diameter. It’s the dampening that’s vastly improved in the F3 forks vs. F2.

    If the bushings are different, they can most likely be made to work by using the F3 inner bushing and the F2 outer bushing (on the chrome fork leg). I utilized F3 chrome legs & cartridge internals with SV650 outer sliders on my bike to get cartridge dampening internals and use the sv650 front wheel & speed sensor.

    Good luck with your project. Also FYI, the VFR shares a lot of those same parts but the length can be slightly different.

    Peter
     
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  3. DonDDR

    DonDDR Well-Known Member

    Thanks for your reply Peter. The calipers are different as the F2 rotors are 280mm and F3 are 320, so the arc and the position where the caliper mounts are adjusted according. I dont see why the early or cartrage type of F3 fork tubes are different. I dont have an F3 tube to play with. Id buy a zesty beer for anyone that had a sht F3 tube I could play with to figure it all out. Used to be able to buy complete stuff for a few hun, now a decade later there is nothing out there. Even the $1500 beater bikes are gone. But consider I live in Oregon, so not much in my part of the world.
     
  4. beechkingd

    beechkingd Well-Known Member

    You can, I've done the same thing with hawks as well (installing the hawk sliders on F3 tubes so I could get cartridges). You need to keep the internals matched to the chrome they originally came with though, I believe the bushings are the same. The F2 had damping rods 90-93 and cartridge in 94 but with the smaller disks. What year forks are you working with?
     
  5. peterleduc

    peterleduc Active Member

    When it comes to finding a whole front end to convert to F3 (best option in my opinion) just be patient and ask around. The wanted forum here and elsewhere will probably get you what you need if you’re willing to wait. Another good option would be to convert the whole front end to Yamaha R6. There’s so many around parts are cheap. I’d say you can find a whole front end/wheel/brakes for $500 and then you’re getting much better stuff to start with.
     
  6. YoshiHNS

    YoshiHNS Mr. Slowly

    Maybe a little more patience and a cheap F3 will turn up. They are out there. I managed to pick up a whole spare bike for $400.

    I have F3 tubes on my 98 VFR800 forks. F3 tubes are about an inch longer.

    DMr did a cartridge set for my F3 forks based on his VFR forks if that's of any interest. Haven't been able to try them yet though.
     
  7. Chuck78

    Chuck78 Active Member

    It is likely that you can just swap the lowers on to the tubes, but as stated, you may want to keep the same bushings or buy new bushings. They are not terribly cheap but very well worth having a tight front end.

    As stated, the last year of the F2 used the same cartridge damping as all years of F3. Even the damper rod F2 forks are 41 mm, same as the F3. So it is likely that you will be able to do the swap you are proposing if you want to retain the damper rod forks. You can get Racetech Gold Valve Emulators, but a full set of F3 cartridge tubes or complete forks would be preferred of course.

    Trying to buy used forks of this vintage on eBay proves to be a complete exercise in frustration, as most sellers do not disclose the full condition of the chrome tubes or even care to thoroughly inspect them, and the majority have some sort of rust pitting on them at this age. It might be worth it to find a cheap set with some obvious rust pitting, and look into buying some replacement fork tubes. this may be perceived as taboo by many, but there is a Chinese company that is manufacturing really high-quality yet affordable fork tubes and selling them on eBay, for MANY Japanese bike applications. I have a set of these Chinese F4 replacement fork tubes, and they seem to be very good quality, although the bike has not left the garage as it is a track day canyon carver "project" at this point. I aspire to run it in Formula 500 some day, but with 37mm GS500 forks (38mm class limit) & Racetech gold valves ('79 Suzuki GS425 2V/cyl parallel twin).

    If you see any F3 eBay forks tubes for sale from China, do a Google search on the manufacturer, you will see many people that have really put them through the paces and were very happy with the quality, saying that they were indistinguishable from the OEM. China has a lot of factories that have really substantially upped their quality output in recent years, as they are clearly on their way to world economic and manufacturing / technology domination! That is not to say that you no longer need to be wary of the cheaply made Chinese crap, however, because it definitely still exists in extreme quantities!

    Best wishes,

    Chuck Lambert
    Columbus, OH
     
    Last edited: Aug 30, 2019
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  8. ducnut

    ducnut Well-Known Member

    Are you sure about that? Should be 298mm.

    ‘98 VFR to ‘98 F3, the latter are only 5mm longer.

    I have VFR tubes, axle, spacers, wheel and discs, combined with F3 lowers and calipers, with Traxxion internals, mounted to a ‘98 VFR.
     
  9. Chuck78

    Chuck78 Active Member

    Yes I did not catch that, but the F3+ are 296 mm rotors. Some of the the later Hondas of this era used 310mm rotors ('98-ish+). 276mm was the F2, whose wheels have a completely different rotor bolt pattern that is much larger, and not much in the way of a rotor center at all. F3+ used 74mm & 78mm bolt circles with the ornate aluminum centers and floating rivets.
    320mm is a race version, if available. I think I do recall seeing that in the EBC catalog, in the EBC Racelite rotors, but they do not work with the stock mounting and calipers obviously.
     
    Last edited: Aug 30, 2019
  10. ducnut

    ducnut Well-Known Member

    298mm was used on pretty-much everything sporty, through 2002. The RC51 was the exception, with 320mm. The 600RR/1000RR started 310mm.

    Webike, in Japan, offer a variety of caliper brackets to run larger rotors, Brembo calipers, and/or radial mounts on standard lowers. However, when I tried to order a set for an oversized/Brembo combo, they responded with an extended backorder notice. In fact, all three items I ordered were backordered. I told them they needed to pull every listing they don’t actually stock, as it’s very misleading to the consumer. Further, they charged my CC. Thankfully, I didn’t already secure the rest of the system and they refunded my card.
     
  11. TZRusty

    TZRusty Well-Known Member

    I have an F3 wheel with 300 mm EBC prolite rotors. $250
     
  12. Kev59

    Kev59 Well-Known Member

    Don, if you weren't on the other coast I would get my F3 back from my mechanic & sell it to you cheap. Shipping would probably kill the deal!
     
  13. beechkingd

    beechkingd Well-Known Member

    FYI the 98 F3 cartridges are a slightly different design to the ones in the 94 f2 and 95-97 F3. As long as you use all the parts from the 98 forks they would fit in the forks the same. The older ones have a long needle screw that adjusts the rebound and the newer ones I think have the rebound valving up higher with a short needle.
     
  14. VFR#52

    VFR#52 Well-Known Member

    if you use F2 tubes and internals the F3 lower sliders bolt right up.
    I used Race Tech emulators on my F2 forks with F3 sliders with F3 front rim and calipers.
    I even made an adapter for piston calipers on F3 rotor and rim.
    the rest is covered here.
    need any parts PM me I have plenty.

    Steven
     
  15. beechkingd

    beechkingd Well-Known Member

    Curious why you would want emulators over cartridges? Personal preference or rules? I've never used emulators, and always found a way to convert to cartridges.
     
  16. VFR#52

    VFR#52 Well-Known Member

    Bahhhahahhaha.
    Because I had them before the cartridge setup was put on F3s.
    And honestly it worked so why change it?
    I built my 86 VFR 750 with leftover parts from F2 sprint bike and F2 Endurance bike.
    It was to be my street bike.
    It turned into my race vintage bike pretty quickly.
    I also have F3 for with race tech valves and the emulators work just as good.

    Steven
     
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