Friday 30 September 2011

I just realised my bikes are Special!

On the special the are a few slight dimensional differences but the quickest way to tell is the pillion peg mounts, here they are just a 'J' shape. On the standard thet are a full loop or 'U' shape. Standard also has two hand holds coming out at the sides behind the seat.



Thursday 29 September 2011

Most Famous Choppers..Built by Unknown Black


Easy Rider's "Captain America" - Mother of All Choppers

Ask anybody who knows a little bit about motorcycles to tell you what a Chopper looks like, and they will very soon refer to that one particular motorcycle that Peter Fonda rode in the classic road movie "Easy Rider".
In the movie, Peter Fonda plays the cool character of "Captain America" Wyatt. As a result, the bike he rides in the movie is also named Captain America.
With its Star Spangled Banner tank, sissy bar, apes, forward controls, chrome frame, chromed out Panhead engine, and the really, really long front fork, Captain America is THE big example of the classic Chopper.
Look at that bike:
Ben Hardy, legendary Master Bike Builder from Los Angeles, had the original Harley Panhead cradle frame raked to 45 degrees. To compensate for the increased rake he increased the length of the front fork by 12 inches.


Ben Hardy - Master Chopper Builder

Both the Captain America Chopper and the Billy Bike Short Chop were built by the legendary yet unknown bike builder Ben Hardy from Los Angeles, CA.
Check this out:





Motorcycle Hand Signals








Rake & Trail



So I am thinking I like my design but need to reduce the trial for a safe amount of cornering, long trail make a very stable bike in a straight line but also very hard to get off that straight course.
Typical trail 4-6" , stock XS650 is 4.47"
Stock XS Specs can't remember which model I go this from.



  • Tire Size 26.1"
  • Rake 27 Deg
  • Offset 1.938 "
  • Tree Rake 0.0 Deg
  • Calculated Trail 4.47"

My Options To Reduce the Trail,  

  • Increase OFFSET DISTANCE - Alternate trees with greater offset?
  • Increase Angle Between Neck & Fork
      •  Offset Neck Cups - Possibly make these but think they add trail same as increasing neck angle, opposite of what I want.
      • Raked Tripple Trees - Expensive option to buy & only for HD front ends.



How Does it all work??

Often mentioned in the main stats when looking at a new motorbike, but what do motorcycle rake and trail actually mean and why would you need to know this? Firstly, these terms refer to steering geometry and so rake, trail and offset effect handling and are directly linked to each other, altering one will effect the other. So if you want to alter the handling, cornering ability or straight line stability, rake, trail and offset are some of the first things that you should look at.

Motorcycle rake

Rake can be described as an angle at which the headstock of the motorcycle is inclined when compared against a vertical line drawn perpendicular to the ground. The rake angle effects steering ability, the smaller the rake angle then the easier the bike is to corner but will be less stable in a straight line.

Motorcycle trail

The distance on the ground between a straight line drawn through the center of the front wheel spindle and a line drawn through the center of the headstock axis. The greater the trail distance, then the greated the straight line stability but the harder it is to make the bike corner.

Motorcycle offset

The distance between a line drawn through the centre of the steering stem/ headstock axis and the centre line of the front fork tubes. Typically the offset inversely affects trail, if offset increases then the trail will decrease.
The diagram below illustrates each of the measurements and how they are calculated:
Motorcycle rake, trail and offset
Basic measurements



A bit more in depth look, when neck & forks are nor parallel.  


Your front suspension geometry is defined by the following six variables which are defined as




  • Offset-- Centerline of top of steering neck to centerline of top of fork tubes.
  • Rake-- The angle in degrees of the steering neck from the vertical.
  • Fork Length-- The distance between the top of the fork tubes to the centerline of the axle.
  • Diameter of the front tire.
  • Trail: Distance defined by vertical line from axle to ground and intersect of centerline of steering neck and ground.
  • Raked Triple Trees-- In order to bring trail figures back into line, triple trees with raked steering stems can be used. Expressed in degrees. Usually adjustable in 3, 5, and 7 degrees of rake.
  • Tire Diameter:
Tire Diameter Formula: If you do not know a certain tire diameter use the following formula:



  • Diam Inches = Rim Diam Inches + [ (2 x Aspect Ratio x Section Width) / 25.4]
  • Example: 200/55R18 Tire:
  • 26.7" = 18 + [(2 x 0.55 x 200)/25.4]

  • Front Tire inchesDiameter of front tire. 21" front typically 27.60". 19" front typically 26.10". 16" front typically 25.30". Hayabusa front 120/70x17 23.61".
    Rake degreesSteering Neck Rake: Softail 31 to33 deg. FXRS models 29 deg. FXLR 31 deg. Evo Dyna FXD/DX/DXT 28 deg. Evo Dyna FXDL/DWG 32 deg. Evo FLH 26 deg. Sportster 29.6 deg. Choppers 36 deg to 45 deg. FLH series 26 deg. V-Rod 34 deg. Early Hayabusa 24.1 deg.
    Triple Clamp Offset inchesDistance from center of top of steering neck to centerline of top of fork tubes. Typically in the range of 2.4". V-Rod 2.0". FLH series have a negative offset ( Enter -2.455")
    Fork Length inchesLength from to top of the fork tubes to the centerline of the axle. Harley forks are in the 30", 32", 34" or longer range. Length will not change trail if the triple trees are not raked. FLH Series 27.75". V-Rod 30". Hayabusa forks are 28.5".
    Triple Tree Rake degreesFor standard triple trees enter 0 degrees: The FXDWG uses 3 degree trees; V-Rod uses 4 degree trees; FLH series use 5 degree trees. For chassis that have been raked to 40 degrees or more, and too much trail is present, Raked Triple Trees are necessary. Enter the degrees of rake, typically 3, 5, or 7 degrees.

    For the functioning calculator go here:


    Trail & Rake Calculator


    Note: Trail cannot be a negative number as this will adversely affect handling unless you are building a shopping cart. 
    Typical trail figures are between 4 and 6 inches. 
    Various Harley models have the following trail figures: 

    • FXR 4.22". Softail 5.0" to 5.8". 
    • Dyna Models 4.1" to 5.1". 
    • Sportster 4.6". 
    • FLH models 6.2".
    • V-Rod 3.87". 
    • Early Hayabusa 3.8".


    The relationship between rake, trail and offset






    • If you increase the rake, the trail increases
    • If you increase the trail, the rake increases
    • If you increase the offset for both yokes then the trail decreases
    • If you increase the offset for only the top yoke/ triple tree then the trail will increase
    • If you increase the offset for the bottom yoke/ triple tree independently then the trail will decrease

    How to alter a motorcycles rake, trail or offset

    So why would you want to alter these values? Well if you plan to cruise mainly straight roads then you don’t want your arms getting tired by constantly correcting and holding the bike in a straight line, so you would want to increase the trail and decrease the rake. Which is why the American choppers have such long front forks to give great straight line stability. If you wanted handling around corners you would do the opposite to allow you to throw the bike around the corners and of course there is a fine balance to get the best of both. Also such inventions like steering dampers allow you to have a very low rake but keep the bike stable by stiffening the steering movement which you can buy as an after market part. So, love the look of the bike and the performance of the engine but hate the handling? Alter these values.
    You don’t need to be a mechanic or an expert to be able to alter the steering geometry and it can be done in a variety of very easy ways, just remember that you’re the one who has to ride it, so you take your life in your own hands. So for instance with my Yamaha XS750 the front forks were originally quite long, which is pretty useless for a cafe racer, so new shorter forks were put in to lower the rake and to improve the handling around corners.
    Motorbike rake and trail are also not only affected by the frame construction but by a myriad of other factors (which you can alter) such as:





    • Rear suspension – lowering it will increase rake and trail
    • Front forks – shorter forks will decrease rake and trail, also you can alter their position in the yokes to help shorten their distance
    • Aftermarket yokes/ triple trees – alter the offset to then alter the trail without affecting rake
    • Wheel diameter – smaller front wheel will decrease rake and trail, smaller rear wheel will increase rake and trail
    • Tyre thickness – same as the wheel diameter

    More importantly when riding the bike, braking and suspension travel will also dynamically alter the rake and trail, for instance, as you brake hard on the front, suspension will compress under dive thus decreasing trail and rake potentially inducing wobble in the bike. Bare that in mind if you make any alterations as you could end up with negative figures under extreme braking conditions. Additionally heavy luggage or pillion on the rear may also effect your rake and trail measurements slightly – which is why you should always alter your rear suspension preload.
    Also remember that while any alterations may seem small and un-noticeable at slow speed at higher speeds their effect will be magnified, such as reduced straight line stability!






    Data collated from Bikearama & RB Racing, amongst  others.

    Wednesday 28 September 2011

    Design Concept II

    This is where I am at trying to factor in all the functional elements to rough scale.


    1. 40 Deg Rake.
    2. 21" Front rim with standard tyre size.
    3. 18"  Rear rim with standard/200mm tyre size.
    4. 4" Ground Clearance
    5. Engine mounts in stock position.
    6. 0 deg Adjustment in triple trees
    7. Stock offset distance
    Need to transfer this into CAD and work it some more.

    The Trail looks to be about 14" I'm estimating which I think is a concern.

    Axle Plates

    Many variations on axle plates out there.

    I like the idea of hidden axle plates though.


    You can get em in different shapes and styles or even cut in a picture, like a ace of spades, or a skull, even flames.


    Inside hidden axle. Not a fan of the point personally.

    Nicely finished with the end caps below.




    David Bird Loop

    Not bad

    Cole Foster Salinas boys


    Chrome plates which are bolt in….Thought I liked these ...

    Looks weird on the bike one painted.

    Bog Round.




    Stockers

    Now this is what I want. Nicely finished.




    It's all in the details,…You can't beat a nicely finished tail end


    Tuesday 27 September 2011

    Change of Heart…….Bobber II

    My original Concept


    Concept Ver II
    New tank, more accurate render of rear fender.
    Stretched up and forward in the front to give the bike a bit more size.

    Standard XS vs Concept II


    H@nd Job….


    The Crusty Old Biker……..?

    A crusty old biker, on a summer ride in the country, walks into a tavern and sees a sign hanging over the bar which reads:
    CHEESEBURGER: $1.50
    CHICKEN SANDWICH : $2.50
    H@NDJOB: $10.00

    Checking his wallet for the necessary payment, he walks up to the bar and beckons to one of the three exceptionally attractive women serving drinks to a meager looking group of farmers.
    “Yes?” she inquires with a knowing smile, “can I help you?”
    “I was wondering,” whispers the biker, “are you the young lady who gives the h@nd-jobs?”
    “Yes,” she purrs, “I am. What can I do for you?” 
    The old biker replies, “Well, go wash your freaking hands, I want a cheeseburger.”




    lol, that was unexpected, lol… . ….

    Monday 26 September 2011

    Just cos I thought it was cool…..

    Just cos she is hot & I thought it was cool…..










    Who says air bags are safe???????









    Boobs or he dies...










    Denied..













    Try this….




    Sunday 25 September 2011

    Sat Arvo Cruising…...


    Took the two girls out for a cruise, and spotted this cool Buick.

    This is why I keep the keys on me & the bike in one piece!……….







    Thursday 22 September 2011

    Clash of the 70's

    Sissy bars now all black. And is very versatile for transporting stuff on the bike!





    This is my mates Kawakka Z900 in showroom condition 22,448Km Original Km on the clock.  His dad bought it new and he bought it from him. Hardley even been on the road.

    Untill a few weeks ago it had the massive front fairing on it and the original panniers.
    Well they are now hanging on the wall. Fairing looks like a giant f/glass moose head!


    Decided it was a good day for a ride and talked Gary into charging the battery on the road.  So we headed out 70's style with the bikes and went for a trip through the winery region.

    Stopped after 2hrs and had a chat about the bikes.  Gary says to me that bikes got some grunt.  I can't hear my bike over the roar of your pipes.  Is it an 850 or 650……Yep only a 650!

    The Z900 has more power but it is heavier and between the fast off the mark and nimbler through the twisty bits the XS was easily a match for the Z900 on this trip.   Wouldn't want to compete in a long straight line me thinks though!….


    The other thing his bike is in such good nick it makes mine  look a bit tired and dirty…………….then mine gets ridden daily no garage princess. She's a working girl lol. What do you expect from a naked lady.




    Monday 19 September 2011

    Imperial vs. Metric

    Was just told:

    I was rereading one of my books the other night and came across something that applys to you. Measure in metric, multipy by 40, call that 0.001"s. If you want the last cut to be 0.1mm move it 0.004" instead, you'll be out by 0.000063" or 0.016mm, not often that that will matter.


    Might help me get my metric mind around my imperial Myford!



    Normally most wouldn't aim to take that much off to get to size without measuring along the way.
    But the math would be

    5x40=200. wind 200 on your crossslide. 200/1000 is 5.08mm so in a perfect world you would be out by 0.08mm.

    Normally I would take somethign like 4mm off and measure again.
    4x40=160 (4.064mm). That would leave you(in a perfect world) with 0.936mm x 4=37.44. Call it 37.5 on the dial. That would take you to a total of 197.5/1000. total of 5.0165mm. See how the error is much reduced and in most cases not worth talking about(depending of course what you are making, but it you are working to that close a fit you would likely use more steps)

    p.s. this ignores that metric lathe crossslides are normally moving half the distance. imp crosssildes aren't like that.
    Myford goodies, Pratt 4-Jaw independant chuck, Myford Swivel Vertical slide, Myford faceplate.    Not sure what the little gears are for. The have a 20 marked on them, the sleeve goes in side them and fits the keyway. Then there is a ring with a locking grub screw.  These bits and the Myford name plates were a little surprise :-)

    If anyone knows what they are for be great if you can leave a comment below.


    Here are all the raw weleded joints.

    Started cleaning them up with a file.  There were a few low points so I decided rather than keep removing metal i would fill with epoxy metal putty and then sand back hopefully less work and a nicer finish.  I didn't want to remove too much weld, and weaken the joints.  Will have to wait for the putty to cure and get back to it tomorrow.