Axle length?……..advantages/dissadvantages

popeyethewelder.com/facebook questions

 

2012

 

  • Carlos Urtiaga – In my knowledge the wider the better in terms of stability. I run a 1.8m axle & haven’t fallen over in a few years, saying that I am away tomorrow for 3 weeks buggying & surfing so lets pray I don’t visit A&E!!!!
  • Bobby Muse – I get along great with my 1360 on my Apexx. I’ve never lifted my upwind wheel by itself. Longer axle would probably need a longer buggy to balance it back out. I’m happy with mine just like it is.
  • Carlos Fandango – For years most of the axle lengths I made were 1600mm long. The PTW Dominator Axle plates were 1600, but to run a cadkat rims you had to add another spacer 80mm each side to stop the tyre chafing the axle plate…making the overall axle length 1760mm….
    The thing I liked about the longer axle more than anything was, I never had to worry how hard I went into a turn on any surface. Most buggies at the time I made my first race type buggy had 1500 axles, mainly because the stock lengths come in 6m lengths and that cuts nicely into four 1500 axles. I was so confident with the 1600 axle at the time, that when I was running Asymmetric hubs, I used to say to anyone, if you can get that buggy on two wheels you can have it, and no one ever did, (just as well I didn’t know Stephan van Bommel at the time)…..but the point being, I had no worries in a turn no matter how hard I pushed it, even on grass.
    When I spoke to Rudd about my Apexx, I asked him for a longer axle, (Apexx axles are 1360mm), I was quite worried about this, being so used to the longer axles.
    Of course, I should not have worried at all, Ruud knows his stuff, I have thrown my Apexx into very hard turns, and mostly I might add with the Landsegler disc wheels on, and have never even been near to flipping the buggy….So this has kinda made me have a re-think on the axle length question….do we really need axles 1600 or even 1500 long?
  • Joshua Walsh – Currently building them at 1524 (60″) and liking it. My old libre was more like 1360 & it would flip on surfaces with more grip. Light buggy though. Might be the difference there.
  • Marcus Edwards – The axle width on my suicide buggy is 700mm and I’ve never flipped it 🙂
  • Carlos Urtiaga – No Marcus because you go too slow!!!!
  • Marcus Edwards – Oi! I’ll have you know I’ve been 40mph no problem 🙂
  • Robin Cook – Hmm. Il answer in a month when I’ve got me new buggy. Flexibug is 1350 and I’ve never come close to flipping and only lifted wheels due to terrain.
  • Carlos Fandango – Its all about triangulation right!
  • Martin Smith – I allways thought the wider the axle the longer the buggy needed to be, aint that why the flexi wide axle adds length to the buggy as well ?
  • Kent Kingston – Wider axles will reduce the chance of flipping the buggy, but it is not all about length. You could put a 2000mm axle on a stock PL XR+ and I doubt anyone could flip it, regardless of how hard you throw it into the turns. The downside is that you lose the triangulation of the buggy making it harder to draw a straight line under excessive power. With the wider axle you drive the downwind wheel into the ground harder – because of the physics and leverage you put on it. This leverage gives it more grip but you will start to unload the front wheel, allowing it to lose traction. The weight and tow point needs to be centered properly for maximum traction. Generally, the longer the rear axle – the longer the overall length of the buggy needs to be to properly load the weight onto the front wheel to keep it planted. For normal cruising you probably won’t notice much of a problem. The issues will start to show up when you load the buggy up and start reaching for those higher speeds. Without the proper triangulation and weight transfer, the front wheel or rear wheels will start to break free, causing your tack line or speed – or both. To see the effect, try moving your buggy seat forward or backwards a couple inches. Usually 2 – 3 inches of seat movement (6 – 10cm) is enough to throw the balance of the buggy off.
  • Jerry Routh – Ok so whats the best ratio between axle width and buggy length. Surely head tube angle will also have an effect as well?
  • Nick TheTog Horler – Jerry I alway thought as a rule of thumb that the ideal buggy should be as long as it was wide putting the pilot in the centre of the buggy well that how I have both buggys and they run quite well !!!
  • Carlos Fandango – 1360 -1600 does it make a difference?
  • Naaman Firth – Just got rid of my 1800 axle. That made a big difference… wouldn’t fit in the garage with the wheels on.
  • Perrin Melchior – my favorite is 1200mm as a good all round dune and beach buggy. But I would say that 1600mm would be needed for the salt pans.
  • David Lees – Over the years, I have had different axle lengths; 1.2m, 1.4m 1.47m & 1.5m.
    I spend half my buggying times in sand dunes riding at unusually steep angles at times and have several considerations when determining axle length.
    1) Stability (has to be long enough to produce the risk of the buggy turning over whilst turning or on a steep slope.
    2) Our dune buggies are built higher to clear dune crests & other undulations, hence the C of G is higher increasing the risk of rolling over.
    3) The buggy length between front & rear wheels wheels & distance between rear wheels has to be optimised to prevent the middle of the buggy bogging down particularly on the dune crests .
    4) On running along the ridges a shorter axle would be preferable. Typically, we won’t straddle the ridge because the buggy underside will drag on the sand but we keep all three wheels on one side of the ridge. One rear wheel is normally kept right on top of the ridge crest. This demands the pilot exceptional pilot skills to maintain a very accurate steering control.
    5) One final issue not related to the bugg’s dynamic performance in the dunes is  that I don’t like to assemble & disassemble my buggy at my buggying site but strap the whole thing on the back of my trailer. A 1.5 m axle plus the two wide offset wheels added makes the width still quite acceptable for transporting through on the UAE roads.

    As you can see for our buggying purposes, the axle length is an optimisation to meet the different demands we have.
    One of my friends has built a 1.6 m long carbon laminate axle. This particular axle has also been designed to flex in order to provide a more comfortable ride.  We do discuss the pros & cons of a 1.5m versus a 1.6m long axle. There isn’t a lot to choose except he has to remove his axle for transportation. That’s not a big issue as it requires only two retaining bolts that are quickly installed & removed.

  • Carlos Fandango – I believe the main reason behind most of the 1500 axles is the stock lengths of tube comes in 6m lengths, so cut equally you get 4 axles. I always made my axle 1600, the dominators were also 1600, but as there were no axle tube to go inside the hub like your normal buggy, the wheels had to have clearance over the 1600 dimension, meaning is I were using beach racers, the overall width was 2200…..this was a major concern for me when I got the Apexx with a 1360 axle, much less than I was used to…..and I had many disscussions with Rudd about it, and he convinced me that it would ok. I have to say in all honesty, I have not noticed the difference at all, and that has surprised me, I can still go into corners just as hard as I did before without raising either of the rear wheels.
  • Craig Hansen – Air Travel postage and shipping as well as stock legnths of tube supply have had a bearing on Axil legnth , so they have not always been made with optimal buggy design in mind. I would be intrested to hear what Wayne Carkeek and Gannets opinions are on this, a quick chat to Peter on this subject revieled stability and handeling is not just all about legnth of axil but also a component of the distance the COG is from the rear axil the closer to the axil the shorter it can be for the same effect (to a point) and the further from it the longer it has to be for the same effect. For example Buggy number to the pilot sat in a seat betwean the wheels, the axil joined the fram about where the pilots hips were, i have riden this byggy and it is a great buggy.
  • Wayne Carkeek – i dont notice the difference between 1500 and 1400 , im a bit Scottish (literally) and tend to use all the material , true 1500 is economic for nominal 6m pipe.  i stick with 1500 its 50mm wider than a 1400 per side and if you run asso rims vs symmetrical it makes a farce of axle width original design anyhow .  the wheel centers move by quite a bit !   a long narrow buggy is more stable but my buggies are super stable so no need to go narrower