30W Non-detergent - Or is there something better?

[chico]

jenson how did you adapt a paper filter to a 305 motor?

[jensen]

Chico,

I explained the conversion elsewhere on the forum, but here the text :

In theory it's a simple conversion, practically it was a little more difficult.

The theory / wishes / engineering considerations stated in 2003 where as follows :

1. All the oil should be filtered before entering the engine, no unfiltered oil entering the engine.
2. As less as possible machining on crank cases, it’s difficult and I can’t change it back in the original state.
3. Because the oil pump is rather a volume pump than a pressure pump the oil filter should have a low flow resistance and a large surface.
4. Changing the oil filter should be really easy, without opening the engine or removing important parts.
5. Should be able to work with 10W50 full synthetic oil, and the oil filter should be easy to buy.

From a logical point of view there is only one place that meets the criteria above and that is a place before the oil pump, so I decided that the oil filter should be placed underneath the pump itself, as a part of the pumphousing.

Another advantage was that the the oil is drawn down by gravity to the lowest point (oil filter) and thus the oil pump itself is not working different than in any other standard engine.

I bought several used oil pump housings to experiment, and finally I machined a three part oil pump housing where the top (part in the engine) stays the same.

I removed the centrifugal oil filter, replaced the oil filter shaft by a direct pipe with a diaphragm to regulate the flow between crank, clutch and head and dismissed the oil filter chain.

After years of optimizing and further development (I destroyed / machined at least 12 oil pump housings) I got what I wanted, I even included a pressure sensor and a temperature sensor. On top of that the engine also gained an extra horsepower due to removing the oil filter and the chain (and less noise from the engine).

I hope that this answers the question,

Jensen

[jensen]

In the mean time I took the engineering a step further.

With an oil pump in new condition this solution works fine. The oil pump delivers enough pressure to overcome the resistance of the filter, and the pressure drop isn't giving any problems.

But when the engine is cold, it takes longer for the oil pump to overcome the pressure of the cold oil in combination with the paper oil filter (cold oil has a higher viscosity). For that reason I had an extra electrical oil pump (low flow, but high pressure) attached which pumps oil to the head before the engine is started. I works fine for me, even better then what will be possible in another way.

But a few CB72 owners here in the region showed interest in this conversion, and of course they don't have a new pump, and neither an added electrical pump. So I was asked if I was able to produce a simple add-on for the CB without all the hassle.

There are a few solutions, using a bypass, or using another type of filter or make the filter surface bigger. I looked around and found non paper filters with a much lower resistance.

At the moment I'm testing this conversion, and I am curious what it will do with the temperature around zero degrees. I'll keep the forum informed if interested.

Jensen

[e3steve]

Thanks, as always Jensen, for stunning, detailed info. My head hurts!

Next time NASA sends up a space shuttle, you can do the Rocket Science and I'll put the plug on the power lead for you!!

[jensen]

Hi Steve,

Thanks for your reply, but since you're the only one I'm not sure weather this kind of detailed information is accepted on the forum. This is one of the reasons why I did not finish the thread of the dynamo / stator. Is this kind of detailed information really appreciated ?

Looking at things in a different way, a more “I want to understand all of it” is a way of live to me, and it pays well. In my work as a vision application engineer and system architect I can make a good living out of it. If your goal is understanding to the full, braking every complex problem down to simple basics, it leads to new ways (idea’s) of doing things. Some idea’s lead to new methods and are patented, even worldwide.

No, I don't work with space shuttles, my CB72's and C77 are my shuttles, and it's difficult enough to understand every process in the engine completely.

The original calculations for the Fc differences are in fact much more complicated, on the forum I used only one formula to describe the process, and a relative easy one. In the original calculations I use more than 17 formula's and a very complex mathematics model to describe the dynamics of the particle in a spinner oil filter, including a complete computer simulation of the forces on this particle with different rpm's (done in math lab).

I did this math because I was interested in the effects of the Fc on particles suspended in a fluid, the shear effects of the fluid on the particle, the shape of the particle, the size of the particle etc to see if such a machine would work before it is build.

Jensen

[e3steve]

Jensen, me ol' Dutch mate, serious research & tutorial; respect to that! Physics is a way of life to me; and I, like you, sometime need to know not only 'if it will break', but 'if it breaks, then why did it break' also.

Your level of research into the spinning filter has stepped into the realms of the original designer's domain. And thanks for the insight into the theory of how it works with different lubricants.

[G-Man]

Jensen

I really appreciate your diligent and analytical approach. To hear your reasoning and descriptions makes me hungry to see some pictures of your work. Keep it up if you are happy to. It makes very interesting reading. I have a degree in Mechanical Engineering but have never really got serious about oil. Your posts add a new perspective to these things.

One has to remember that Mr Honda did the best he could with a budget. There is always a better way, especially after 40+ years. With your effort and analyses It may be possible to make our old 'bikes last much longer than we ever imagined..

G-Man