Changing Rake Angle

Discussion in 'The Garage' started by OHjim, Jan 1, 2013.

  1. OHjim

    OHjim Been here awhile

    Joined:
    Aug 12, 2009
    Oddometer:
    522
    Location:
    KC
    I am modifying a Honda Shadow and am considering changing the rake angle. I have been playing around with it in CAD and think I can go from OEM of 32° to 27°, possibly even 26°, without having to extend the headstock out too far and keep clearances, etc. Anyone with experience doing this? What are the pitfalls/things to consider? I am thinking of cutting it at the yellow line and extending it thinking it will help to have the material on the headstock to keep it straight and vertical. Or should I grind off the weld on the headstock? The concern with grinding the weld is the VIN number/tag on both sides.

    [​IMG]

    Any comments will be appreciated.

    Jim
    #1
  2. Motomedic

    Motomedic Over-caffienated Raconteur

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    Oct 4, 2004
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    2,600
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    First thing that comes to my mind was "why?" :dunno

    Second was does he have enough clearance between the front fender/wheel and radiator/front cylinder etc at full compression?

    Then I thought about what that'll do to your trail. And I wondered about the fork length.

    Ans yes, keeping the original VIN tag is good.
    #2
  3. OHjim

    OHjim Been here awhile

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    Because I am raising it up and with the 32° rake, it makes the wheelbase grow from 61" to about 62.5". Also, I have to have longer forks with 32° than with 27° (36" vs 34 7/8")

    It will - that's why I need to extend the headstock out a bit - I cannot just "roll" the top of the headstock forward.

    The original trail is about 5.5". Changing to 27° will make it around 5.25". Original fork length is 33.25" and with 27° it will need to be lengthened to 34 7/8" which is only 1 5/8" longer. With the 32° rake, it has to grow to 36" which is 2.75" longer.

    The other thought which might be a decent compromise is to just extend the fork 1.625" and leave the headstock alone. This would give about 31° rake and 5.1" trail. The wheelbase would only grow about 5/16". Travel would be about 5.8" which matches the rear well at about 5.5".

    Note that this is all CAD layout and I think I have measured the stock configuration correctly.

    OR I could go all out and try the Hossack front end . . . . .
    #3
  4. Worroll

    Worroll Been here awhile

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    I'm going to ask why are you raising it up? When I had my 86 VT1100, I was surprised at how well it could be thrown around in the corners and day dreamed about kicking in the rake and shortening the swing arm to get it to really rail. It was something I knew I'd never have the time to do but always thought it would be cool to do.
    #4
  5. OHjim

    OHjim Been here awhile

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    Changing ergos to do touring with ability to do some gravel roads (longer travel suspension).
    #5
  6. JAB

    JAB Unsprung Weight

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    Beautiful Monrovia
    A quick Google search turns up "offset bearing cups". They show a 3 degree change. Don't know if that would even work, but it might be better/easier than cutting the frame. Good luck.
    #6