Based on the GPM listed for the Ryobi, and some assumptions on the properties of the hose, properties of water, etc... a .25" diameter 25 long hose will produce a significantly larger pressure drop than a .375" diameter 50 ft long hose when calculating the losses due to friction (both of which are small in the grand scheme of things).
I did some basic calculations to show this...
50 ft hose, 0.375 in diameter...
25 ft hose, 0.25 in diameter (using same assumptions as in the 50' .375" D calculations)...
The more critical part of the system downstream from the pump is the nozzle. The nozzle is what generates the output pressure by effectively reducing the area for the water to flow through. This is why I purchased a new set of nozzles that are appropriately sized for the flow rate of the pump and the desired output pressure using the chart found in the PDF I had provided a link to.
"The nozzle does not create the pressure in and of itself. The pressure washer pump creates a specific amount of flow. By damming the flow with nozzle, you create the pressure—much like when you put your thumb over the end of a garden hose to create a more powerful stream of water. The nozzle is part of a system and must be properly sized to be correctly paired with the flow of the pressure washer. Putting on too small a nozzle can over-pressurize the pump and cause problems. Putting on too large a nozzle lowers the pressure, meaning a loss of efficiency and cleaning power. "
Link for Reference
If you read through my OP, you will see a link to a PDF which has photos, descriptions, and links to all of the parts that I purchased.
To replace your hose, you just need to find another hose with the same connection (assuming it isnt a proprietary connection like the Karcher), or use a converter to change from whatever size connection your PW output is to a more common hose size like I did (convert from M22 to 3/8").
The flow rate and water pressure of most household water supplies is way more than is needed for a tiny pressure washer pump.
Having a 50' hose allows me to connect my PW to the water supply and maneuver myself around my entire driveway (and previously in my entire shop when I was a professional) without the need to move the pressure washer. A 25' hose means I would have had to have placed the PW fairly close to the vehicle, and then it would barely reach around both sides of a larger vehicle.
Like I said, the PW functioned just fine... it was the little things that really bugged me over the 4+ years I owned it. The hose, the spray wand, the parts falling off of the unit, etc.
Again, as was said in my OP, the Karcher operated perfectly fine. No one is disputing that. As a whole package, it is my opinion that the K5 was lacking in terms of quality of sprayer, hose, gun holder, cord holder, etc. that did not justify the 3x price over the cheap unit I have purchased. Upgrading the cheap unit with high quality parts for a lesser price than the K5 has made, for me, an ideal car washing unit.
Agree... the internals of the unit are nothing to be upset at. They work as expected and were perfectly fine for me... it is the attachments (hose, sprayer, wand, hose holder, cord holder, etc) that were poor and should have been higher quality for the price tag IMO.
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Originally Posted by zmcgovern45
Based on the GPM listed for the Ryobi, and some assumptions on the properties of the hose, properties of water, etc... a .25" diameter 25 long hose will produce a significantly larger pressure drop than a .375" diameter 50 ft long hose when calculating the losses due to friction (both of which are small in the grand scheme of things).J/K
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