My expanding teardrop trailer build

[Shiney]

....
Dont forget that we are limited to 100 Kph. whilst towing, and if this speed is observed the effective wind resistance is in reality quite small when compared to what  would experienced at a higher speed.
That is  if you were to double your speed the wind resistance would be increased by 400 percent. and that would be massive.
Cheers . winston66

  So no riding at 200kph with a trailer in WA   Damn

[Abe]

I'm lead to beleive (Teardrop trailer tragic for many years) the original teardrop trailers were made from old aeroplane wings cut into sections, they were cheap and they basically put an axle under them.

google teardrop trailers and start to dream.  Thinking of building one to go behind the hotrod (finish car first)

In short Sicman, Winston has less drag when towing like Steveo said.

[Williamson]

 

...... economy went from an
average of say 18.5 Klm. per liter for one up ,It dropped down to an average of about 15.0 Klm.  per litr. Whilst towing.....

Just had my first tour (around 400km) with the Elite camper behind the ST1300.  Fuel economy went from 16.5km/litre down to 13.5km/litre. 

The ST1300 has around 1,800km on it now, still being new, perhaps the economy will improve some more as it loosens up.  Having said that, I'm pretty happy with that so far, as the CB1300's fuel consumtion was more in the 15.0 to 15.5km/litre.

Despite the ST being approx. 80kg more than the CB, the fuel consumption is better.  I put this down to the fully faired and taller geared ST.  The CB was revving at around 4,000rpm at 100km/h, compared to the ST at around 3,200rpm - I have not worked this out as yet as I'm sure the speedo is reading over by 5 or 6km/h at 100km/h. 
Perhaps someone can enlighten me on this point. 

Back to towing.  The CB1300 towed the Classic trailer (100kg) and load (up to another 120kg in trailer) with ease and fuel consumption was around 13.5 to 14km/litre.  Close enough to the ST1300 (Elite camper 165kg) and load (another 60kg).  Sorry I have to say this but the ST1300 does not seem to have the same GRUNT as the CB1300.

Some hills where the CB would pull well in 5th gear and even a bit in reserve, I find the ST needs to be in 4th (proably the same as the CB's 5th), but then sometimes I need to change back to 3rd.  Perhaps that 80kg has an effect here?

Aerodynamics?  Well the Elite is as aerodymanic as a brick, because it is a BRICK!!  Probably would get a lot better economy towing the Classic with it's rounded, smooter, lower profile.  The Teardrop camper trailer would probably be better again.

I missed where the mass of the Teardrop was mentioned (if it was).  Any ideas on that point?

[winston66]

Winsto66.

Hello everyone, I have just checked the gross weigh and as it stands in the driveway ,fully loaded with beer, esky, ice , tinned supplies for a week; gass cooker, 5 liters of spare fuel, 6 liters of water and all the needed personal stuff. spare wheel and a assortment of tools, bedding , etc.and all the extra shit that you could ever want, it tips the scales at 190 Kg , including the 10 Kg draw bar weight.
How does that sound.

Cheers , winston66

 Ps   as an aside I figure that as the ST is fairly highly geared this seems to help the fuel economy as it does not have to exceed 4000 rpm. which seems to me to be just coming into a sweet spot , Which is at just about one half of the available rev range capability of this motor, and If I drive in 4 th. gear for any length of time , but not through the ups and downs the fuel consumed is increased.
Ie it uses less in top gear, if you are not pushing it , without lugging.
After all that is what a gear box is for.

[alans1100]

Just had my first tour (around 400km) with the Elite camper behind the ST1300.  Fuel economy went from 16.5km/litre down to 13.5km/litre. 

 an average of say 18.5 Klm. per liter for one up ,It dropped down to an average of about 15.0 Klm.  per litr. Whilst towing.
A lot seemed to be dependent on how heavy I was on the throttle whilst accelerating and if there was a stiff head wind or not, as well as to

Seems comparable to my 1100 figures when towing.

The classic trailer which I've had since Jan 2011 is a little larger than than my first trailer and I have noticed a change in consumption as well.

But generally around 15k/L is the norm now with throttle lock on and just letting it run and it will sit between 90 to a 100 kph (3000rpm +/-).

[Sicman]

All good answers  . I was in the Air cadets years ago so was interested to see who in here was aware of why the tear drop trailers are shaped like they are. The air plane wing effect helps to push the trailer along and thereby reduce the drag effect of the larger front end i.e saves fuel.

[STeveo]

People worry about the flat front end causing drag, it's not the front but the back end that causes so much drag as the air tries to come back together. (Follow a big Pantech truck and watch it swurl up dust from the side of the road. If you ride 25me behind you will feel the buffeting, ride 100me behind and you will be back in still air.) The flat front of a Kenworth truck builds up a buffer of relatively still air in front of it and the rest goes around this and down the sides, under/over the truck. The air going through the radiator is moving at around 1/5th of the road speed (20Km/h at 100Km/h) and this has the effect of making the engine run hotter than common sense would think. (Note the scoop under the bumper of some trucks). Air can be though of like a liquid (eg water) in its flow patterns, so think about the back of a yatch and how it is smoothly shaped. Bikes are very 'dirty' when it comes to smooth flow with a lot of turbulence behind them. Hard to explain without drawings.

 

[Yorkie]

A yacht doesn't get blown along it is sucked as the air pressure on the non wind side is twice the pressure hence we get so much buffeting behind the screen, air is trying to fill the vacuum.

[gaz]

....
Dont forget that we are limited to 100 Kph. whilst towing, and if this speed is observed the effective wind resistance is in reality quite small when compared to what  would experienced at a higher speed.
That is  if you were to double your speed the wind resistance would be increased by 400 percent. and that would be massive.
Cheers . winston66

  So no riding at 200kph with a trailer in WA   Damn

 

[Rodd]

Great trailer project, Winston! I like the way that you have taken advantage of the basic trailer, you have come up with your own adaptation of it, and you have actually taken the project to it's final stage (by building it).
There are some great 4WD camper trailers out there that allow you to quickly set them up for over night stops, and have quick access to kitchens for roadside meals. They can also then be set up for longer stays (with their annexes, etc). Something that is harder to do with the size limitations of a m'bike trailer.
An expanding trailer is a good idea. I have noticed the lost area of the draw bar that needs space to clear the bikes' panniers while maneuvering the bike. This space can be used when the trailer isn't being towed; as you have done.
 

[winston66]

Thanks for the nice comments everyone.
I must admit that I do like doing this sort of thing, It stops me from watching the grass grow.
I am now on to my third trailer build in two years.
What I want all this stuff for is a question that I cannot answer.
I just just that I am curious as to how all these thing will work and the only way that I can find out is to make something and then try it out.
I want this one for next years trip to the Nationals and then the rest of the trip around the paddock on the way home .
I figure the teardrop design whilst it is everything that I could have hoped for, it will increase the fuel consumption a fair bit over the anticipated 20,000 klms. and so a more fuel efficient design will probably pay for the new build.
Also  by having less cargo space I will not be halling as much (probably unneeded stuff)
My poor old dad used to tell me that the easiest and most useful stuff to carry when on a trip is MONEY
This latest build is going to be a mono wheel one with a very streamlined profile.
I have most of the body profile laid out already ,using 5 mm. round rod as the basic for the frame material , and I am using a discarded scooter chassis complete with the telescopic forks and its front wheel as the basis of the new chassis.
The towing coupling arrived today. I am using a ADR approved 2000 Kg assembly, Which is totally overbuilt for this application , but the RTA. regs" cannot be circumvented so I have taken the easiest way out for me and bought a a standard 4 Wd. Poly block coupling and when fitted I will just weld it solid in the vertical plane so that the  trailer will stay upright as it follows along behind the ST.
Some pics. will be posted shortly as the build progresses and there is something interesting to see.

Cheers , Winston66, Northampton W.A.

[Lionel]

Some years ago mono wheel trailers were advertised for sale.
They couldn't be registered in the ACT because the trailer (the distance between the rear lights) wasn't wide enough.
I don't remember the brand but I remember that Barry bought one for his BMW in Victoria.
Do other states mandate a minimum distance between the rear lights on trailers, mono or otherwise?

[winston66]

There has been an amendment to the ADR, Qld. which I believe that the other states have accepted.
 IB-12A states It will be acceptable for the rear lighting fitted to these specific single wheeled trailers to comply with the requirements for motorcycle ADR.  lighting requirements.Etc.
Specificatly The separation of the rear indicator lights require the inner lenses to be at least 240 mm. apart, etc,etc,
The UNI-GO brand name gets a specific mention and because of the lack of body width.
The inspectors are issued with a directive that  they are not to issue a Defect Notice if the vehicles non compliance aspect is the above mentioned technical non compliance with the ADR's
So it figures , that the Sauce for the Goose is , sauce for the Gander.
I think that I will be Ok.
Cheers ,
Winston66

[Couch]

Look forward to viewing pics when you have them Winston!!

[winston66]

As an aside to my previous post, a trailer must be fitted with a regular sized number plate.
These plates measure 370mm. in width.
I have designed the bum of this single wheel trailer to accommodate this and also have an extra bulge ,or extension each side of the number plate of about another 70mm.
This will provide plenty of room for the fitting of the LED. lighting clusters (stop, & tail,& the turning indicators). that I am making up.
The  tail or running lights will be a dual dual operational, and will work in conjunction  with the stop lights ie, increase in brightness,and act also as stop lights,with the  other,(4) separate stop lights.
I am planning to mount this stop tail,  light, cluster (A total of eight individual eagle eye 3 watt leds,) across the full width of the rear of the trailer and they will be positioned  nice and high above the number plate. They should be very easily seen.
The indicators will be mounted slightly lower, at the sides of the number plate.
Now I guess that it is all as clear as mud.
Cheers Winston66