Very well thought out soliver. I would have to agree on the good to bad ratio of PL buggy. It's a economy buggy. And, like anything "economy" there is always the "next level up". I was also told by reputable people here the PL buggy is a great buggy to enter the sport with. It suited me fine and did what was promised. It allowed me to enter the sport, learn how to ride, and have a blast on a budget. I would certainly not hand a 1,2,or 3k ride to a newb. I doubt anyone else would risk their investment either. Also, not too many people can drop that kind of $ getting into the buggy side of the already ridiculously addictive and expensive hobby. The PL buggy is mass produced no doubt. With this type of production, there will be defects!! Just like anything similar.

Custom buggies are a different story. More time spent on building, better quality control, higher grade raw material, etc. But, this comes with a price. A $600 PL buggy wouldn't even cover the material cost on some of these buggies out here, let alone the build labor cost. This thread has had some very good thoughts behind it with a little bit of debate even. In my most humble opinion though, the PL buggy does serve a great purpose in that it allows the average working man to have fun, and bring new people into the sport who may be on a tight budget. No different than golf clubs, firearms, mountain bikes, etc, etc, etc. There are setups to get you started, and there are setups that pros use that cost major $$$.

Heck, my post here may even be subject to debate, but that's just my thoughts on the topic.

The production buggies are thin wall tubing. The UNDERCUT (a major defect) weakens the base metal by washing away metal , leaving a sharp gouge in the tubing thereby creating a stress riser,which will cause cracking. Combine that with a heavy load,throw in some slides,bumps and whatnot. The next thing you know it's cracked. High speed isn't that much strain,bumps and sliding are far worse. Your steel buggy Van made has thicker walled tubing,it may even be pipe. You will be fine. And 22mph is nothing,you will go faster and not even realize it. Then you will do it again .Then you will go out of your way to go faster.

Well think I'll have to pad up with some 'Charmin' next time I go out!! I'm also going to get my head checked (short visit I'm sure). My lil kite trike is holding up pretty well for me so far. @ 230 and riding on grassy fields so cracks yet. Would I go faster than 40 with it????? YEP more than Once sure. LOL
WG what's you take on proactive approaches to eliminate catastophic failures? Going to be putting buggy up and if I can address issues over winter would be perfect time.

Brian,there is a fine line between fatigue and failure. You don't get much notice. Look for small cracks at welds. Watch for bending as well. Unless you have access to NDT equipment, there is not a lot you can do to find defects. If you think it's "not acting right" ,stop and check it out.

Soliver, speed is all about perspective. I still remember how fast it felt when I broke 25 mph at OOBE field that blustery day. It felt WAY faster the next time I was at Jekyll and came to understand what a broad reach does and was hammer down at over 35 mph.

At Ivanpah, there isn't much sense of speed at all till you get over 30 mph. At 20-25, you are totally relaxed and wishing some wind would come along to give you a ride. The day is a bust if I don't go over 40 mph, and 50 mph happens almost every time out. That being said, Brian Holgate usually rides on his little XR+ when we ride together. In the light winds, he has an advantage over me with he and his buggy being lighter, so he can go faster than me in the lulls. In decent winds, we are well matched and ride right beside each other, provided we both have the right kite out. He can hang with me right up to 50-52 mph and then can't handle any more power from his kite. My buggy and weight are just coming into the zone at that speed and I can start to pull away from him.

I've never seen him break a buggy part on his XR+ even while this is the scenario most every time we ride. Ivanpah isn't smooth everywhere either. There are some tire tracks that run along the gasline and they can bounce your tires off the ground which is exciting when you are going fast and skip sideways 10-15 feet.

So I feel the XR+ can handle most smooth riding. I don't think speed is the biggest test a buggy is put through. I think the bouncing on a grassy field is much worse, then consider what stresses it puts on the buggy when you are cruising along on a beach and hit one of those 4-6" deep rivulets. And then there is just big boys plopping down in the seat with some momentum. These are the stresses that push minimalist mfg materials past their limit.

@BB,

Yeah, that's what I'm gathering from what WG said above. For some reason I was under the impression that cruising at speed with the forces at work making the buggy move were what was under question, esp. when taking buggy strength into consideration. I had not even considered how the "bumps in the road" tested the weld strengths. All my riding spots are grass fields, but are relatively bump less, but now I know...

And like G.I. Joe said, knowing is half the battle.

Quote: Originally posted by soliver

@BB, Yeah, that's what I'm gathering from what WG said above. For some reason I was under the impression that cruising at speed with the forces at work making the buggy move were what was under question, esp. when taking buggy strength into consideration. I had not even considered how the "bumps in the road" tested the weld strengths. All my riding spots are grass fields, but are relatively bump less, but now I know... And like G.I. Joe said, knowing is half the battle.

Like the welders and metals guys said above, the metal can give and take a little while stressed and bounce back to original. But push it really hard like on a hard bounce and you can push it past what it can recover from, especially with thin materials and substandard welding.

Having a failure is worse and worse as the speed increases though. If you broke something earlier but it hasn't shown itself yet, the torque on the buggy frame due to a high speed run could cause it to fall apart when you'd most like it to stay together.

Quote: Originally posted by ChrisH

Try this, take a piece of 12"x1"x.125" stainless and mild steel tubing, weld them both to a metal table and then hit them with a hammer and see which one moves/cracks/bends/breaks etc.

I've been thinking about this a lot lately. What if those same strips of metal were welded to a table of the same material for each strip. Weld the 1" end to the table so the 12" is pointing up. Now start flexing both materials back and forth and see which one work hardens and breaks first. I kinda think this is the case with the thin wall stainless buggy. It's flimsy and can only be flexed so many times. I think if it was stout and made of heavy wall material; it would never break.

But I still wonder about thin wall mild steel because bicycles don't seem to have the same issues but maybe there it is more of a design issue and difference. Plenty of "cheap" lightweight 10-speeds from the 1970's out there still being ridden.

Also too the design or manufacturing decision to use autogenous welding and take away material from each piece to fuse them together instead of adding more material from a welding rod; I don't think was the best choice. Peter Lynn really should reconsider that choice.

Considering the price these buggies are going for these days; they really should be top quality.

I thought the going price of $550 for the little folding model several years ago was outrageous then. Have you seen the current prices of buggies lately?

http://www.bigmikeskites.com/PeterLynn/Buggy/PeterLynnBuggy....

Quote:

But I still wonder about thin wall mild steel because bicycles don't seem to have the same issues but maybe there it is more of a design issue and difference. Plenty of "cheap" lightweight 10-speeds from the 1970's out there still being ridden

Bicycle frames often have lugs the tubes sit in at the joints instead of being welded directly and unreinforced. But many bike frames skip the lugs. So let's go there.

Not any expert, but seems that bike frames get a special boost from their geometry...being a closed triangle...each of the three joined tubes keeping the joints or their 'vectors' from spreading wider under stress...and also where same force is distributed along triangle and not just joint.

Geometry angle also effects the force applied.

Two words ....... HEAT TREATMENT

It is more that strength is not the issue in bicycle frames. The issue is stiffness.
Don, I await with baited breath to hear how you are going to improve the strength of the low carbon mild steel, they build cheap bicycles from, with heat treatment. You need a higher amount of alloying or carbon to impede the austenite to ferrite transition. You can not get a cooling rate high enough to form marteniste by conventional heat treatment. There are ways to get cooling rate high enough but they are to costly to use on bicycles. You should know that from the Jominy bar.
S
PS lugs are used on some brazed frames, never seen them on welded ones.

I will not jump into the fray more than to relate that I'm not sure what WELDNGOD did to the aluminum in MY buggy but it's built like a tank and I'd trust it with my life. In fact, I already do every time I sit in it. He cites "strength by design" and I'm sold on that concept.

Quote: Originally posted by riffclown

I will not jump into the fray more than to relate that I'm not sure what WELDNGOD did to the aluminum in MY buggy but it's built like a tank and I'd trust it with my life. In fact, I already do every time I sit in it. He cites "strength by design" and I'm sold on that concept.

Yes riff. WG's rides are insanely tough built!!

I don't have any metal knowledge but there is no comparison between the forces on a 2 wheeled bicycle frame and a 3 wheeled buggy frame that is concentrating stress on the welds as the buggy moves over uneven ground.