Edited for spelling, formatting, and to thank the mods for moving it to the right place.
Hello! I'm a long time lurker who has finally decided to create an account. I've recently done something a bit crazy and have found myself in need of a little advice since it actually worked.
I ride a Chinese-made Hawk 250 motorcycle. The engine is an enlarged clone of Honda's CG125 engine developed in the early 70's. If you're familiar with old/small Honda motorcycles, you'll know that they don't have a true oil filter, but instead use a combination of a wire screen and a centrifugal oil separator to clean the worst debris from the oil. This works well enough, but it leads to a rather short oil change interval of 400-600 miles depending on how hard I ride. That means I'm changing the oil every 2-5 weeks since I use it as my primary transportation. Oil is cheap enough(or, it was), and an oil change is only about 15 minutes of work, but it's still a little annoying to do this so frequently.
I tried running an oil cooler for a while and it helped a little, giving me an extra 50-100 miles depending on the time of year, but unfortunately both readily available types for this engine have rather unfortunate flaws. I won't go into too much detail unless someone wants me to, but suffice to say one showed signs of inconsistent oil flow/circulation, and the other will inevitably leak due to a design issue. Since I greatly appreciated the benefits of running with the oil cooler, I set about finding a different and more effective way to feed oil through one.
The more I thought about it, the more I thought it would be nice to be able to run the entire oil supply through the cooler AND keep good, consistent flow. The best way to do that would be to plumb directly into the oil pump outlet, and if I'm already doing that, then I should be able to add in a more modern type of oil filter.
A year's worth of planning and a couple of days of work later, and amazingly enough I pulled it off. I successfully tapped the pump outlet, installed a filter adapter, and plumbed it right back into the engine and it works great! The entire supply of oil is now running through a filter, and I can tell a notable difference in both clutch feel and acceleration from the cleaner oil. I pulled an oil sample(roughly 200 miles on it) before installing the oil filter assembly, and will be pulling another sample in about a week to compare. I also have a pair of oil pressure sensors hooked up with display giving me real-time readings from the input/output on the oil filter adaptor. I will be adding the oil cooler sometime in the next few days.
The problem I have now is figuring out how to determine my new oil change intervals. My current plan is to do the first change on schedule in a couple of weeks and dissect the filter to inspect the media. If it doesn't look too bad, then I'll run the next filter an extra 250-ish miles or until I see a significant variation in oil pressures. Then, repeat the process until I get a comfortably high number(2k+ miles) or I start seeing signs of the filter becoming too clogged. I know with the wet clutch I will see much more particulate buildup in the filter, so I'm not planning on shooting for the moon.
Does this seem like a reasonable plan? Are there any issues/concerns with my current plan for progressively upping the mileage until I find a limit? I've never done anything like this and honestly wasn't sure I'd make it this far at all, so I'm just flying by the seat of my pants. Any input/advice at all would be greatly appreciated!
For the record, the current setup is as follows:
Rotella T4 15w40 oil(occasionally T6, but usually T4)
Briggs and Stratton Vanguard oil filter mount
Supertech ST3614 oil filter(will be replaced with a Motorcraft FL400S at next change)
3/8" transmission cooler hoses
Data I've gathered so far:
Idle pressure: 2psi-5psi inlet, 1psi-5psi outlet depending on engine temperature
Peak pressure: 38psi inlet, 34psi outlet
Cruising pressure: 10psi-15psi, depending on engine speed and temperature
Fairly consistent inlet/outlet pressure difference of 10% across full range of speed and load. Numbers all line up with pressures seen using mechanical gauges with old oil cooler setup. Engine has good oil flow to head and there have been no signs of pressure/flow issues anywhere in the engine.
TL;DR: Added a spin-on filter to my motorcycle, looking for assistance figuring out my new oil change schedule.
Hello! I'm a long time lurker who has finally decided to create an account. I've recently done something a bit crazy and have found myself in need of a little advice since it actually worked.
I ride a Chinese-made Hawk 250 motorcycle. The engine is an enlarged clone of Honda's CG125 engine developed in the early 70's. If you're familiar with old/small Honda motorcycles, you'll know that they don't have a true oil filter, but instead use a combination of a wire screen and a centrifugal oil separator to clean the worst debris from the oil. This works well enough, but it leads to a rather short oil change interval of 400-600 miles depending on how hard I ride. That means I'm changing the oil every 2-5 weeks since I use it as my primary transportation. Oil is cheap enough(or, it was), and an oil change is only about 15 minutes of work, but it's still a little annoying to do this so frequently.
I tried running an oil cooler for a while and it helped a little, giving me an extra 50-100 miles depending on the time of year, but unfortunately both readily available types for this engine have rather unfortunate flaws. I won't go into too much detail unless someone wants me to, but suffice to say one showed signs of inconsistent oil flow/circulation, and the other will inevitably leak due to a design issue. Since I greatly appreciated the benefits of running with the oil cooler, I set about finding a different and more effective way to feed oil through one.
The more I thought about it, the more I thought it would be nice to be able to run the entire oil supply through the cooler AND keep good, consistent flow. The best way to do that would be to plumb directly into the oil pump outlet, and if I'm already doing that, then I should be able to add in a more modern type of oil filter.
A year's worth of planning and a couple of days of work later, and amazingly enough I pulled it off. I successfully tapped the pump outlet, installed a filter adapter, and plumbed it right back into the engine and it works great! The entire supply of oil is now running through a filter, and I can tell a notable difference in both clutch feel and acceleration from the cleaner oil. I pulled an oil sample(roughly 200 miles on it) before installing the oil filter assembly, and will be pulling another sample in about a week to compare. I also have a pair of oil pressure sensors hooked up with display giving me real-time readings from the input/output on the oil filter adaptor. I will be adding the oil cooler sometime in the next few days.
The problem I have now is figuring out how to determine my new oil change intervals. My current plan is to do the first change on schedule in a couple of weeks and dissect the filter to inspect the media. If it doesn't look too bad, then I'll run the next filter an extra 250-ish miles or until I see a significant variation in oil pressures. Then, repeat the process until I get a comfortably high number(2k+ miles) or I start seeing signs of the filter becoming too clogged. I know with the wet clutch I will see much more particulate buildup in the filter, so I'm not planning on shooting for the moon.
Does this seem like a reasonable plan? Are there any issues/concerns with my current plan for progressively upping the mileage until I find a limit? I've never done anything like this and honestly wasn't sure I'd make it this far at all, so I'm just flying by the seat of my pants. Any input/advice at all would be greatly appreciated!
For the record, the current setup is as follows:
Rotella T4 15w40 oil(occasionally T6, but usually T4)
Briggs and Stratton Vanguard oil filter mount
Supertech ST3614 oil filter(will be replaced with a Motorcraft FL400S at next change)
3/8" transmission cooler hoses
Data I've gathered so far:
Idle pressure: 2psi-5psi inlet, 1psi-5psi outlet depending on engine temperature
Peak pressure: 38psi inlet, 34psi outlet
Cruising pressure: 10psi-15psi, depending on engine speed and temperature
Fairly consistent inlet/outlet pressure difference of 10% across full range of speed and load. Numbers all line up with pressures seen using mechanical gauges with old oil cooler setup. Engine has good oil flow to head and there have been no signs of pressure/flow issues anywhere in the engine.
TL;DR: Added a spin-on filter to my motorcycle, looking for assistance figuring out my new oil change schedule.
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