VF1000F Conversion to Full Cartridge Forks

Discussion in '1st & 2nd Generation 1983-1989' started by JamieDaugherty, May 27, 2008.

  1. JamieDaugherty

    JamieDaugherty New Member

    Country:
    United States
    Joined:
    Aug 26, 2006
    Messages:
    2,389
    Likes Received:
    26
    Trophy Points:
    38
    Location:
    Fort Wayne, IN
    Map
    Here's one that I started about a year ago but only recently finished up. After doing many RaceTech Gold Valve Emulator conversions I wanted to go further. It's not that the RT parts suck, quite the opposite in fact, I just wanted something more.

    I started out with a spare set of 1000R forks (basically the same thing as the F forks) and a set of bent Ø45mm CBR900RR forks. I pulled the cartridges out of the CBR forks and made adaptors to allow them to fit inside the VF forks. This required an extension to the bottom of the cartridge sleeve and some spacers to allow the VF springs to be used. I then took the CBR caps and machined the proper thread and seal groove to fit the VF forks. I also shortened the stroke by 25mm (why in the world the stock pogo sticks have so much travel is beyond me). I'm starting out with 15w fluid but I really do not know how close the valving is going to be. I'm expecting to need some adjustments. At the same time I'm curious as to how much better/worse this is than the RT valves. If nothing else it opens me up to a world of possibilities with the valving that aren't there with the RT setup. Enjoy.

    [​IMG]
    [​IMG]
    [​IMG]
     
  2. GenLightening

    GenLightening New Member

    Joined:
    Nov 5, 2006
    Messages:
    248
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Minden, NV
    Any good reason to reuse the stock lowers? I want to lose the antidive mount and run some 4 piston calipers to get some real brakes on it. Would it be easier to run some normal forks (GSXR, FZR, CBR) and make gullwing triples to get the clearance for the front wheel? I made an adjustable offset set for my FZR1000. I may just have to start on another set..... where's that billet I had left over?:drool:
     
  3. JamieDaugherty

    JamieDaugherty New Member

    Country:
    United States
    Joined:
    Aug 26, 2006
    Messages:
    2,389
    Likes Received:
    26
    Trophy Points:
    38
    Location:
    Fort Wayne, IN
    Map
    Yeah, there is a good reason: cost. The triples you mention would be really expensive. Besides the Teflon impregnated hardcoat anodizing I have about $50 total invested in this project.

    Another reason, though not as important for me, is to maintain a stock "look." The whole purpose of this modification was to see how good I could make the stock forks perform.
     
  4. GenLightening

    GenLightening New Member

    Joined:
    Nov 5, 2006
    Messages:
    248
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Minden, NV
    Gotcha. Of course, that's always the reason, isn't it! I might have to try it next winter (too many projects right now), do some horse trading for some forks and go to town on the mill. I have the engine, I just need the front suspension and brakes to go with it!
     
  5. Sebspeed

    Sebspeed New Member

    Country:
    United States
    Joined:
    Apr 22, 2006
    Messages:
    621
    Likes Received:
    2
    Trophy Points:
    18
    Location:
    Catskill Mtns, NY
    Map
    Bump for you. Any progress?
     
  6. JamieDaugherty

    JamieDaugherty New Member

    Country:
    United States
    Joined:
    Aug 26, 2006
    Messages:
    2,389
    Likes Received:
    26
    Trophy Points:
    38
    Location:
    Fort Wayne, IN
    Map
    Nope, I've been too busy with shock conversions to even give that bike a second look. Poor thing, that's been it's life for the past several years.
     
  7. JamieDaugherty

    JamieDaugherty New Member

    Country:
    United States
    Joined:
    Aug 26, 2006
    Messages:
    2,389
    Likes Received:
    26
    Trophy Points:
    38
    Location:
    Fort Wayne, IN
    Map
    Bump....


    After some more work I've found the 15w fluid to be too heavy. With some shim stack adjustments and 10w fluid I should have it dialed in pretty well.
     
  8. crustyrider

    crustyrider New Member

    Joined:
    Jul 27, 2008
    Messages:
    5,012
    Likes Received:
    1
    Trophy Points:
    0
    Location:
    North Country, New York
    Map
    that red one off to the right ....doent get rode much does it...(expired tags)

    as usual Jamie...good stuff
     
  9. mrich12000

    mrich12000 New Member

    Joined:
    May 10, 2009
    Messages:
    269
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Calgary, Alberta.Canada
    Map
    Nice, let us know when we can purchase them Jamie..
     
  10. JamieDaugherty

    JamieDaugherty New Member

    Country:
    United States
    Joined:
    Aug 26, 2006
    Messages:
    2,389
    Likes Received:
    26
    Trophy Points:
    38
    Location:
    Fort Wayne, IN
    Map

    Actually, it's because I did this three years ago! That VTR is my daily rider, the VF's only get a couple of tank fulls of gas put them each year.



    I've been doing this for other's already. It's fairly time consuming so normally I work with each person to determine what is best for them. I just finished a set of VF500F forks which were a particularly challenging. This is a great way to improve the performance of the front suspension for a reasonable cost, reletively speaking of course!
     
  11. invisible cities

    invisible cities New Member

    Country:
    United States
    Joined:
    Oct 20, 2009
    Messages:
    2,259
    Likes Received:
    2
    Trophy Points:
    36
    Location:
    new york
    Map
    Vf500f

    What modifications did you make to the stock VF500F forks?
     
  12. JamieDaugherty

    JamieDaugherty New Member

    Country:
    United States
    Joined:
    Aug 26, 2006
    Messages:
    2,389
    Likes Received:
    26
    Trophy Points:
    38
    Location:
    Fort Wayne, IN
    Map

    The biggest modification to the VF500F forks involved the oil lock at the bottom of the stanchion tubes. Because the VF500F forks are a smaller tube diameter it makes it tough to fit the cartridges inside. That meant I had to remove the oil lock but keep some of the other parts in there. That was not easy to do! For comparison, the VF700/750 and VF1000 forks do not require any modifications to the stock parts.

    There are several custom parts that I have to fabricate to make the cartridges fit. It's also important to note that not all cartridges can be made to fit. You need to have enough material in the fork cap to machine the correct mating geometry for the top of the stanchion tubes. I think the most difficult part is setting up all of the lengths such that you have clearances, the correct stroke, and you can make everything fit. This is not a trivial process and usually takes some time to work everything out.
     
Related Topics

Share This Page