CBR600F2 to Dual Sport-ish/Off-Road Tourer?

Discussion in 'Some Assembly Required' started by getout, Sep 23, 2011.

  1. getout

    getout Adventurer

    Joined:
    Apr 13, 2010
    Oddometer:
    14
    Location:
    SLC, UT
    So, I'm looking for a winter project and something to fill the spare bedroom in our apartment (not that it isn't packed full as it is...but there's no motorcycle in there yet).

    I'm thinking about working to turn a early '90s CBR600 into something like:

    [​IMG]
    http://www.advrider.com/forums/showthread.php?t=644390&page=72

    Any thoughts? The engine is an inline 4 and I'm a little worried it'll be too much weight out the sides as it's not inline front to back.
    #1
  2. sailah

    sailah Lampin' it

    Joined:
    Aug 12, 2005
    Oddometer:
    7,066
    Location:
    Turning expensive metal into scrap
    Ha, were you reading my mind today? I'm finishing up my other !-4 build and wanted this old CBR out of my garage. Never occurred to me to do another build but it looks like a great candidate if I can keep the weight down. I threw the subframe on it and took a pic this afternoon.

    I will probably take things in a slightly different direction than you will as I already have a frankenbike with luggage. This build will be a day trip bike with the emphasis on simple. I might even ditch the tank and run an underseat tank to shift the weight back.

    With regards to I-4 being a good candidate for builds, it's yes and no. They are typically very reliable, smooth, efficient. Minor cons is that they are wider than a V or twin. Major cons are that any sport bike engine is just not geared right for anything really off road. They'll do fire roads and trails fine, but you won't be hounding XR's offroad due to the tall first gear and the close ratio gear box.

    If your idea is to make a V strom type bike, they are a winner. Too bad you're not closer, you could come take my sig bike for a spin to see if it's worth it. Most guys that have ridden it agree its pretty wicked.:deal

    Getting a CR front end on any bike is (relatively:lol3) easy. My concerns for my other bike were strong braking which meant 2 rotors. If you can keep the weight down, having one rotor is totally doable. You might find it difficult getting heavy enough springs for the weight of a CBR with CR forks, but I don't think that would be a major problem.

    The biggest challenge you will give yourself is if you try and modify the rear suspension. Trust me, it snowballs quick. I decided to go for a KTM swingarm as I wanted the WP shock to match the front travel-wise. This essentially tripled the amount of work from everything from a custom subframe, machine work etc. What you gain is full travel suspension like a KTM 950. I was willing to do it, but like I said it tripled the work and added a lot of money. I love the results just don't know if that's what you want to get into.

    For this build you and I are both considering, I would probably stick with the stock swingarm, maybe lengthen it a couple inches. I measured my YZ swingarm and its 23.5" center to center and the CBR is a few inches shorter. I might redo the suspension mounts in order to fit a dirt bike shock but preserve the linkage, that saves you room where the seat would be going. If you stick with the stock CBR shock, you might find it lacking in travel compared to the front. The cheap way would def be to leave it stock.

    Then you need to either go wire wheels or maybe V strom type wheels. A cush drive DR650 or KLR wheel would work well I think and then adapt the caliper mounts.

    Have fun, it's a lot of work and difficult to see the light at the end of the tunnel, but the rewards are sweet.

    [​IMG]

    [​IMG]
    #2
  3. heat762

    heat762 n00b

    Joined:
    Sep 23, 2011
    Oddometer:
    1
    Hello,
    First time posting on this site. Please do the conversion. I have a spare XR400 rolling chassis and this site has convinced me I can shoehorn a parallel twin in it, or use the suspension on a sport bike. Oh no!
    #3
  4. getout

    getout Adventurer

    Joined:
    Apr 13, 2010
    Oddometer:
    14
    Location:
    SLC, UT
    Well, I went and took a look at what I thought was going to be my project bike. The 'complete bike' that just needed the 'carbs installed' turned out to be in about 10 million pieces with 2 other bikes with all the parts scattered in the grass in the backyard. Once I got there he didn't have the title but promised he could 'get it.'

    I told him to get the title and call me. With ALL the parts he had from the mess of bikes, I figured I could do something with it, but trying to sift through it all to pick out the CBR bits (which upon arrival I found he didn't have the front end or front wheel) would have turned into a nightmare.

    Looks like I'll keep shopping.

    I'm pretty sold on the Hondas though and as my budget is just a fraction above $0, anything I get will have to be super cheap to start.

    Thanks for the advice! As soon as I find something I'll start posting.
    #4
  5. OaklandStrom

    OaklandStrom Long timer

    Joined:
    Sep 17, 2005
    Oddometer:
    1,624
    Location:
    East Bay