as much money that quads, car, semi, and tractor companies spend on this stuff.......and they are all still using gears and belts(on occasion)......I'd have to about bet that is the best way, that we know of.

 

Hey Doctorturbo. I don't think anyone will argue what is more efficient. The question is, is the hydraulics good enough? So lets compare a shaft drive ATV (2wd) at 35% loss to a hydraulics system with 10-15% in the pump and 10-15% in the motor. We put a single hydraulic pump on the engine. We put a single hydralic motor on the rear axle. This configuration represents 20% to 30% loss (comparable to gears!!). I think you are missing some important details when you compare a car with an ATV. The car does not have all the gears that the shaft drive ATV has. Now if you insist on this unrealistic comparison, then I will point out to you the comparison that all LARGE construction vehicles use hydraulics and 500hp is nothing in that world!

Next lets look at a high tech hydraulic solution to ATVs. That means putting hydraulics on each of four wheels. This solution gives you something that no other quad has. However, the 10-15% losses are not additive. You cannot simply multiply 5 pumps/motors times 10-15% to get 50-75% losses. The reason is that very rarely are we transfering equal torques on all four wheels. Furthermore, individual motors can be dynamically shut off, so efficiency increases.
Bryce

 

Bryce.......I live on a farm and we farm around 2200 acres....with John Deere equiptment. None of our equiptment is powered by hydraulics.....they are all gear driven(other than combine is hyrdostat...which is acutally belt driven)......



We do have hydraulic capabilities on our tractors, but they are only used for accessories(dozer blade, loader, etc)......and hydraulics require lots of power, and high rpms(to get max power out of them).....

 

its just a matter of time

the technology is still in the infant stages

after they get the bikes figured out it will work its way into our market (too much money not to)

 

LOL, you need to look at the hydraulics on the Yamaha cycle. It requires neither high speed nor high power to work. There are many other examples of similar uses of hydraulics.
Bryce

 

Yep, you got it!!

 

well I don't exactly have one to look at.....but I'll take your word for it.....



I also said high rpm's not speed.....but I'm sure you just mistyped that.


Next.....if you plan to run this......is it as reliable as quads are now?? Will it be able to hold up to the rocks, sticks, etc? What happens if you bust a line(or loose presssure)?? Any back up plans?? Also.....how much heavier would this be??

 

BryceGTX you keep on going back to bogus figures. Your figures are off, way off. You don't believe me and that's fine.
You say my analogy with the car is bogus because it does not have enough shafts, gears ect. What about a 4X4 truck? It even reverses the power 180 degrees. What about a diesel truck with duel drivers?

Here is the bottom line for me. I have other hobbies and work that deal with hydraulics.
To drive a wheel with hydraulics is nothing new. Here is one of my other hobbies; and this company deals with what you are all talking about. These people have one of the best juice motors on the market for what you are talking about. They know how, and do build what you are after.
My other hobbie

I want you to key in on the HP of the motor they use and the speed of these things. Granted, they are using two more tires and wheels but there is still a big loss. Also, look at the cost. Most of it is in the hydraulics. A similar unit with no hydraulics is about 1/2 to 2/3's the cost and twice the preformance with the same HP. BTW, look at the cooler they have on the system for just a 43 hp motor!!!!!

Hydraulics are good for one thing. Jobs where you need to make enormous amounts of power through fluid multiplication, and don't care how long it takes to make that power. In short, they can do huge amounts of reliable work; but they do it very slowly. IMHO not a good application for quads.

 

OK then.. What numbers of mine are wrong? So give us the efficiency of these things!! If they are so bad why did Yamaha use hydraulics on the front tire?
So whats your point? Whats this got to do with quads? Once again I suggest to you.. COUNT THE GEARS
Good, so if you're the expert, give me the efficiency numbers. BTW whats this got to do with quads again?
I suggest that you look very closely at the hydrostatic transmission used in the Honda ATV called the Hondamatic. Then come back here and tell us all how hydraulics cannot be used in quads and how inefficient they are.
Bryce

 

As far as I am concerned, reliability and durability is designed in. If you want it reliable/durable, design it as such. If you bust a line, shut off the flow to that line. As far as weight, thats a good question, but don't discount it if it has never been done. Why should it be any heavier. You replace a bunch of shafts, gears, transmission parts with a few motors/pumps and a few small high pressure hoses. I suspect it has more to do with costs than anything else.
Bryce