Sidecar Design Formula - IMPORTANT!

Discussion in 'Hacks' started by Get Back, May 25, 2009.

  1. Jeff 8

    Jeff 8 Been here awhile

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    Too fine, on the ones I have anyway. The 1/2 inch thread has 20 tpi which could be either.

    Jeff

    :2guns
  2. Jeff 8

    Jeff 8 Been here awhile

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    So I turned up some bits to match the Watsonian fittings I had laying around only to find the 'free machining steel' is unsuitable for welding. Should I start again with different steel and maybe turn these into threaded fittings?

    WP_20170124_003.jpg
    They aren't for attaching a sidecar, just a jerry holder and rack, but thought I'd use what was in the garage.

    Jeff

    :2guns
  3. RidgeRunner56

    RidgeRunner56 Adventurer

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    Free machining indicates the presence of lead in the steel...which as you note is not conducive to welding
  4. High Octane

    High Octane Long timer

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    ThreƔd them and use them
  5. Jeff 8

    Jeff 8 Been here awhile

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    Would brazing do the trick?
  6. Strong Bad

    Strong Bad Former World's Foremost Authority

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    Cracking is still a problem when brazing is what I've always heard.
  7. Old Mule

    Old Mule Long timer

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    Wot, no advances in sidecar design for two months now???
  8. rantingsmith

    rantingsmith Quadrilingual blacksmith seat of pants engineer

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    I was talking to a guy that brazes competition racing wheelchairs who pointed to the fact most old bike frames were brazed, his take was that if done right brazing is stronger than tig or mig as the brass alloys with the parent materials in a more gradual way.. also the frame on my Watsonian has all collars and mounts brazed on, brazed very nicely but brazed.

    On a different note, I have come across two things I haven't seen before both adaptations made by Turbodog over on VTF when mounting his chair to an XV920.

    Firstly, because of space restrictions the front exhaust runs through (!) the subframe..

    Secondly, when trying to up the spring rate of his forks he used stacks of different rate shorter springs from Amazon to replace the progressives he had..


    He had this to say about it:

    The spring selection process:
    I found the 3 springs linked above on Amazon, searching by 1" OD. I made a spreadsheet looking at combinations of these, compared mostly to the specs for Progressive 11-1117.

    [​IMG]

    Then I removed the sock springs, and found they only measured 22 inched long. I expected them to be longer.
    I added the last combo to the chart. I then tried it out, putting 1" fender washers between each spring. I had to compress the spring stack about 1 inch to get the fork cap on. I sent the unused springs back. Gotta love Amazon.

    As you can see, I gave up a fair amount of travel, but the forks do not ever bottom out. I am not running any air pressure.


    Cheers,

    Rant.
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  9. Old Mule

    Old Mule Long timer

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    Seeley, Rickman, and many other frames are brazed, an English method called "Sifbronze". It has worked well for generations.
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  10. claude

    claude Sidecar Jockey

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    Earler watsonian frames were brazed
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  11. davebig

    davebig Another Angry Hun !

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    It's held allot of bicycle frames together also ! Sifbronze refers to the type of rod used.
  12. rantingsmith

    rantingsmith Quadrilingual blacksmith seat of pants engineer

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    I'll try get a shot of the brazing on mine next week, it is rather impressive!
  13. Jeff 8

    Jeff 8 Been here awhile

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    Before we get off on a tangent about brazing, it was meant specifically about brazing 'free machining bright mild steel' also known as 1214. Not about brazing in general.

    Jeff

    :2guns
  14. rantingsmith

    rantingsmith Quadrilingual blacksmith seat of pants engineer

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    That's fine Jeff, I just interjected as from that initial mention it seemed that brazing as a whole was being slated.

    Cheers,

    Rant.
  15. ken williams

    ken williams Adventurer

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  16. ken williams

    ken williams Adventurer

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    The statement-if there is pull add a bit more lean. The lean is designed for neutralization. After seating oneself the bike leans to the right to a neutral position and is no longer leaning left. If the rig pulls it is because of other factors and not lean. Remember toe in is very small. Motorcycles originally used two tires of the same width. Today they usually have a wider tire in the back. So when measuring for toe in measure down the center of the tires and not on the outside or your toe-in will be off. After 40M miles my sets of tires are worn out show even wearing and can be constantly checked looking at dirt on the tires to note my contact with the road. If tire wear is off and there is pull go over the general installation of the sidecar. After 65 mph your sidecar will begin to pull and have handeling problems. Sidecars were never meant to exceed 65 MPH except for some racing types. I run with about 35 lb PSH due to increase weight of a sidecar and has been advantageous for handling especially on dirt roads . Stay away from slick tires and use Dunlop vintage type tires if you ride dirt roads. My sidecar is a strongly engineered Cozy Europa with Susuki 800cc, previously was a 650 V star yamaha. My best days run is around 800 miles . Motoken PS Afteryou ride a motorcycle with a sidecar you are hooked up for life. Love them.
  17. claude

    claude Sidecar Jockey

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    Hello Ken...I agree totally that sidecars and a ton of fun and quite additive. Glad you are having fun with yours and it is serving you well. Hope what I am about to write is taken well.

    We are talking conventional sidecars here just to make that clear for everyone and hopefully curtail any confusion.

    LEAN OUT is the main static adjustment that provides straight tracking. This is defined as leaning the bike away from the sidecar to resist a pull toward the sidecar. TILT on the other hand is leaning the whole rig in the direction away from the pull toward the sidecar. TILT can be manualy adjusted or done so with a linear actuator that picks up or lowers the sidecar suspension. TILT should be thought of as a fine tuning adjustment where as LEAN OUT is the main thing to get things close.

    Road crowns, passenger weights, loading of gear and such in sidecar or on bike can change TILT whereas the initial leanout remains the same as related to the sidecar to bike connection. Note also that an antiswaybar is somewhat of a self compensating device to help tilt from being all over the map due to the circumstances mentioned previously.

    As a sidenote it is common that Discussion boards on the net seem to talk toward 'absolutes' which may apply under most circumstances but there are exceptions from time to time.

    There are also other factors that come into play. The suspension on the sidecar related to that on the bike can be a factor once on the road. If the sidecar is a little stiffer sprung and then loaded weight transfer will go the the bike quicker to prevent the whole rig from leaning (tilting) toward the sidecar when a passenger gets in. This is not a bad thing. A really soft sprung rig is much harder to find a 'sweet spot' with than a stiffer sprung outfit.

    TOE IN? If we think of toe in as keeping all the play out of the various swinarm piviot points and wheel bearings it is a safe way to describe it. Too much toe in will create tire wear (usually the rear but sometimes the sidecar depending on tires size variations and such) No toe in will create a wandering feeling if one os sensitive to it and does not confuse it with reduced trail or tire variations. Toe out will pull you toward the sidecar and wear tires quickly due to a reverse snow plow effect. Note that on reverse pivot swingarms toe in can be even more critical due to the inability of the sidecar wheel to 'caster' behind as a front pivot will usually do. Swingarm pivot bearings or bushings are more critical on a rear pivot swingarm. Yes measuring tow in can be done with centerlines as you mentioned. If going this way it is good practice to insure that the front and rear tire track one behind the other. Some may be surprised but all do not. If using a straightedge on the outside of the wheels use only the rear and sidecar wheel and NOT the front. It is good practice to do two things first....Number one: Spin the wheels and check for run out. Number two: Place the valve stems at the bottom. Why? If there are any variations you will be measuring in a way that can be duplicated. It is best to get the straightedges up as high a possible to get away from any tire bulge. So air up the tires quite high which is also not a bad idea. Some keep the straightedge away from the tire and measure to the rim in two places which is probably the best way to go. We normally go for between 1/2" and 3/4" or toe in measured just in front of the front tire and just in back of the rear tire. Yes, there are variables related to wheel lead, track width and such and there are formulas to work with also that can be used. This does make sense especially when wheel lead and the bikes wheelbase and track width is thrown into the equation but that is another story.

    Your statement : " After 65 mph your sidecar will begin to pull and have handling problems. Sidecars were never meant to exceed 65 MPH except for some racing types." Sorry but there are superslabs out there that if you stay below 65 You will be your own hazard. Solution? Stay on smaller roads? I hate interstates but most here will admit they run them whether they like them or not. They are good for getting from point a to point b but in many cases the only way to do that safely and not be a hazard to yourself and others is to run with the traffic like it or not. If a rig begins to 'have handling problems' at speed it IS NOT setup right. I have had many a rig far above that with no 'handling problems' as have most here. We won't go into the ZX14 hps rig nor even the Rocket 3 rig I had but will say the ZX14 exceeded the Rocket 3 that was well into the triple figures on the speedometer . Handling ? Not bad even at irresponsible foolish speeds.

    Have fun be safe and enjoy many miles of smiles.
  18. claude

    claude Sidecar Jockey

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    BTW the first post in this section is a write up by Peter Smith (Brock's father) of what was Side Effects and is an excellent read.
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  19. claude

    claude Sidecar Jockey

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    One thing to check on any given sidecar rig to see how it will steer is to turn the bars from lock to lock while watching the sidecar wheel. If it moves a lot it may be hard to steer...if it moves none or a little it will be Easier to steer. The results are due to trail, track width and wheel lead.
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  20. ROADOG 62

    ROADOG 62 Aint done yet

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    I'am about to be hacked by Claude. Getting a CSM1A on my 2013 Triumph Explorer. Cant wait, excited
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