Motorcycle vs Car Oil Filters

I thought my post had made it clear, but I'll try to sum it up. It's not just about "fit"; it's about ALL the filter specs.

Your oil filter typically will rarely, if ever, go into bypass. It's been debated here many times, but most agree that it just doesn't happen but in EXTREME circumstances, and even then, it's still rare. The bypass filter is designed to open upon pressure differential across the media; upstream pressure vs. downstream pressure, if you will, as divided by the media within the fitler. This might happen as a blip at start up. It could happen if you get a GIANT sludge filled agglomeration mass covering the whole media (but if this were true, you'd have bigger problems than filter bypass!). The filter itself represents a mere fraction of the lube system resistance, therefore the differential across the media isn't going to force the bypass open. If you're worried about the filter bypassing at ultra-low rpm, you're worried about the wrong thing. Basically, this is a non-issue.

As for flow ratings, it's typical that the flow capability of a filter FAR outpaces the flow of the system in an engine. So flow is also a non-issue.

Nominal micron ratings are better than no info at all, but the Beta ratios are a MUCH better indication of filtration efficiency. Regarding the filtration need for the HD oil cooling jets; do you think HD is the only manufacturer to use such technology? MANY, MANY of today's sport bikes use such cooling. And they do it at a MUCH higher RPM. Heck, even some diesel engines have jet cooling for the pistons. What makes HD so special in this regard? Nothing, that's what. Just because HD has a "premium" 5um filter available for sale, that does not mean that the engine requires such filtration for proper operation. And I seriously call into question any filter that claims to be a 5um FULL FLOW filter.

I can assure you that large companies such as Wix and Purolator spec filters that will meet the OEM criteria for all characteristics. Size, flow, filtration, bypass and burst pressures, etc. Do you honestly believe Wix would suggest filter XXXXX for an HD application, to risk "serious potential problems"? If anything, HD owners tend to be super-anal about their rides, overall. Don't you think Wix is legally aware of their obligation as implied in their warranty?

The OP's question was basically "what makes a motorcycle fitler different from a car filter?". Answer: nothing. Specs are specs. As long as a filter meets those specs, it'll work.
 
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You might want to take a close look at the oil system design on a Harley Evo or TC engine before you say the system will hardly ever go into bypass. It is a high volume/low pressure system which is very different from sport bikes. The EVO is very sensitive to which oil filter is used. The internet boards regularly have guys with EVO engines posting about lubrication issues especially with an oil filter that is too restrictive. The HD lube systems wil go into bypass frequently because of the design. Which is one reason they have an internal bypass check valve. You can't relate the experiences of any other Motorcycles with the Harley air cooled designs. Just too different.
 
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OK. I'll take that as good info. Do you have any specific references or such that I can read up on? Any links?

I've owned a few HD's, but never fell in "love" with them. Got out shortly after I got in. Just realized after a while, they weren't for me.

I do know that, due to the design nature of the 45deg V-twin with common crank pin, there has been, is, and always will be and oil level/crankcase pressure issue. Two HUGE pistons going up/down at nearly the same time makes it hard to control the presssure/vacuum cycles. That's why they use a dry sump system in the first place. A wet sump has a difficult time tolerating such vast and violent pressure changes. How that plays into lube system pressures is NOT a direct issue, but it does speak to some of the specific problems unique to a HD type engine.

As I recall, a dry sump type system uses two pumps. One is a low pressure, high volume scavenge pump that takes oil from the bottom of the crankcase and pushes it to the oil tank. Then, the oil feeds from that tank to a high pressure pump that supplies all the bearings, etc. This is how the Honda XR650L and such has been for years. Is the HD similar? If not, what differences exist? The reason I ask is that there is a difference between the oil pump bypass relieving, and the filter bypass relieving. I cannot resolve in my mind why the filter bypass would relieve in typical operation, but perhaps there's something more than meets the eye.

Still, I have to believe that Wix, Fram, Purolator and such would NOT have a direct recommendation for a filter that would jepoardize, or otherwise put at risk, any piece of equipment that they would have to pay for, presuming a failure of the filter, that didn't meet the engineering specs. On that note, I'd think you'd have to agree.

Further, do you have any direct information you can pass along (links, etc) that shows the specific HD specs for filtration and/or lubrication? From what I've seen, HD is very tight lipped about such info, preferring to have the HD faithful buy the HD branded stuff. For the longest time, HD didn't print much but their logo and grade on a bottle of oil. If there's something "special" about an HD oil filter, I'd love to see it in it's raw form. What is the filtration spec for the HD engine filter. That's a specific question. I realize they may sell a "premium" filter of micro-glass and such, but that's not required for proper operation. Just as we are all not required to run an Amsoil EaO filter on our cars, trucks, etc, there is likely no "requirement" of such a filter on the HD. It's likely a feel-good appliance added to the HD lineup.

For years, and even now, HD wants you to use their branded oil, but for goodness sake, if you've seen a few VOA's on the stuff, it certainly isn't anything special. I suspectd their filters are similar. What HD can evoke into brand loyality has little to do with the reality of where their specs stand. HD certainly isn't alone. Honda oil and fitlers aren't "special" by any standard either, unless you count in the price they want!

I'm not trying to be rude, I just have the annoying habit of wanting to see proof to reconcile facts in my mind. I love technical data. It's where the shade-tree gear-head meets the degree'd engineer in me.

Also, keep in mind that you're exempting a very specific relationship here from the OP's question. I still stand by my comment that there is no such thing as a motorcycle filter, or a boat filter, etc. Filters are made to an engineering standard of specs. As long as an aftermarket filter meets those specs, it is suitable for service and the OEM cannot deny warranty or otherwise blame the aftermarket item(s), realtive to the Magnuson-Moss warranty act, without proof of failure, and how the product(s) in question relate to the required specs.
 
I don't have any links but ask any HD wrench and he will tell you that all HD Vtwins go into by pass at every cold start up. The double gerotor oil pump which has one pump gear & one scavenge gear flows lots of volume but develops only 30-38psi under load (much less at idle)so the system relies upon oil volume moving through the engine uninterrupted. Now add some new hydraulic tensioners in the 96 engine and you need 5 micron filtration to keep those gunk free or else. Then add the bigger stroke & higher rotational mass of the 96 and you generate more heat than in the TC88 design configuration. SO the oil filter spec in this engine is critical to longevity from numerous angles. Add the fact that any damage done by using an oil filter not up to these specs will be so subtle & gradual that you will be out of warranty before any symptoms show up. The HD design guys have this system at it's maximum threshold so IMO changing any of the lube system criteria (oil filter is part of that) could cause a problem.

I have seen a couple of reports where guys have lowered the idle on a TC88 EFI model and worn the engine out of tolerance within 10,000 miles due to oil starvation which required a complete rebuild. That was reducing idle speed about 150rpm. (950-800)Interestingly, the engine was not making noise but the owners noticed gradual power loss to the point where they took it in for diagnosis.

BTW, the HD filters for the TC engines state 5 micron filtration on the box.

And if you want to know how different a HD Vtwin engine is hook a vacuum guage up to one sometime....you will see readings all over the place. Very very old time basic design they are still trying to optimize to suit the customer and the EPA at the same time. I think they will have to water cool it sooner or later as I am doubtful they will ever get one to pass the 2011 EPA specs.
 
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Lots of good info here guys. I asked a pretty broad question and got a ton of answers. The question I was trying to get at is it fine for me to use the Purolator PL14610 on my bike currently instead of the OEM Honda filter. I am not under warranty, so that isn't a concern for me, however engine longevity is.

Good stuff guys.
 
Send me the HD part number for the filter you're referencing and I'll try to do some research on it. Still doesn't seem all the "special" to me.

It's my opinion that ALL filters go into bypass for a split second upon start up (if they have a bypass). But that doesn't last but for a fraction of a second. Once the total resistance equalizes in the oil lube pathway, the bypass will close. The HD engine is no different than any other pressure lubed system in that sense.

Regarding the bearing wear, I'll agree that low rpm can contribute to that. But that is not effected by the filter. The volumetric flow through the filter is not the main restriction to the system. The tight tolerances in the oil pathways are the main restriction. Therefore, the oil filter is NOT the contributing issue for oil starvation.

One of the main functions of the lube system is to seperate components from contact during motion, right? The pressure head of the oil system must be great enough to provide sufficient volume to have a rotating part "float" above a stationary part. What many don't realize is that the boundry layers of oil along the two parts are stationary, and as the flow moves towards the center of the action, it's velocity becomes greater. The spinning of the crank and cam and such actually create a hyrodynamic wedge, ala hydro-planning of sorts, that allows the moving component to float over the stationary one. If an oil filter can flow enough volume at full RPM to sustain this interaction, then a lack of flow at low rpm is not the fault of the filter, it's the fault of the pump. If an owner purposely drops the rpm of the engine at idle (very common for braggin' rights to some HD owners), then the low pressure supplied by the pump is to blame for the bearing issues, NOT the filter flow.

And again, I understand that the HD filter says 5um on the box. But I want to know what the spec for the lube system is. What PC and efficiency rating did HD design the engine for? Just because they make a super-duper filter, doesn't mean that's what's required for operation.

Get me some part numbers or reference manuals and I'll try to help figure this out.

BTW - in general, I don't trust many mechanicas at all. For me to ask an HD wrench jockey for his opinion just isn't my nature. Most (not all) of them are not my idea of well educated in the world of tribology, filtration efficiency, etc. Yup - they can turn a wrench. And yup - they probably got some certificate from some HD or motor cycle mechanic school. But I've had too many experiences to prove otherwise. In fact, if you went to 5 different HD dealerships and asked 5 different "mechanics" for their "opinion" on the very topic we're discussing, you'd probably get 1 answer; "We use what HD says, 'cause it's the best". Most of them are just as brainwashed as the rest of the HD faithful. They cannot compare and contrast the merits of lubrication. They just burp out a pre-programmed answer. On top of that, mystique runs DEEP in HD circles; it's very hard to get facts on HD topics. You get a lot of "he said this" and "they say that", but FACTS from documented sources; that's rare!

But in no way is that unique to HD. All the other major m/c brands are just as bad. Brand loyality often blinds those who stay within the fold.
 
Originally Posted By: MidnightG35X
Lots of good info here guys. I asked a pretty broad question and got a ton of answers. The question I was trying to get at is it fine for me to use the Purolator PL14610 on my bike currently instead of the OEM Honda filter. I am not under warranty, so that isn't a concern for me, however engine longevity is.

Good stuff guys.


Yes.

Actually, we use the L14610 (Premium Plus) .vs "PL" Pure one now because the "PL" series is that stupid gold color.

If you like a OEM length Purolator use the 14612. It's a little shorter and it's white and I have to tell you that a $2 rattle-can of your favorite color will spray-paint a LOT of white filters.

Works for me.
 
"All of us Harley-Davidson sheep just buy the Harley Genuine oil filters because they're chrome. That's the REAL answer."

Untrue.

But it's funny!
LOL.gif
 
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HD part # 63798-99a and you can get them in black on the internet for $6-7. So why not use them?
 
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Why not use them?

It's a matter of choice. Or, more appropriately, it is a matter of what is "best" as defined by each individual.

"Best" might mean least expensive, longest lasting, highest efficiency, some compromise of the three, etc.

I just have NEVER liked being tied to only one choice when it comes to anything. Options/alternative are important to those who cherrish freedom.

I'll see what I can find out about this HD filter.

Thanks for the info.
 
OK. Did a little research on the part number you provided.

Here's my synopsis of 63798-99A ...

It's more Harley Davidson marketing at it's finest. Period.

Depending upon what web page you want to believe, it's either a 5um or 10um nominal offering. Further, it's intended to be a one-size fits all replacement, or maybe not. Also, depending on what enthusiast web page you want to follow, the "A" suffix either does or does not mean it's chromed. Even the HD afficianados can't agree on what it is.

http://www.latus-harley-davidson.com/Genuine-Harley-Davidson-Oil-Filters-4.htm

http://www.v-twinforum.com/forums/evolut...il-filters.html

http://xlforum.net/vbportal/forums/showthread.php?threadid=201893

Now, let's agree that Wix and Baldwin are two top contenders for quality filters at a reasonable price. They are not the only vendors, to be sure, but they are very good at what they do. They both offer a few different options for HD motorcycles, depending upon application. Some are chrome, some not. Some flow a bit more than others. Etc, etc. The bottom line is that even these filters have multiple applications; not just HD, but Mazda's, Toyota's, cars, truck, motorcycles, etc. Don't believe me? Look them up at http://www.wixfilters.com and http://www.baldwinfilter.com

What is clear to me is that Harley Davidson has found yet another way to bring the sheep into the fold, and get the cash.

Is the 63798-99A a good filter? Possibly so. But even HD calls it their "SuperPremium" filter. It's meant as an upgrade. It's a feel good option that is not REQUIRED for proper operation of the motorcycle; it's an upgrade.

Here's a direct link to the HD official site:
http://www.harley-davidson.com/gma/gma_p...&bmLocale=en_US

"63798-99A
SuperPremium5™ Oil Filter
Fits all '99-later Twin Cam and Evolution® 1340-equipped models and available as an upgrade for any motorcycle that requires Oil Filter P/N 63796-77A, 63805-80A, 63812-90 or 63813-90.
Chrome
MSRP US $13.95"

Notice that they state " ... an upgrade for any motorcycle that requires ..."
There you have it. It's an upgrade. It's NOT required.

It's no different than choosing a Fram, or a Wix, or an Amsoil filter. There are always different choices for grade and quality. I will not disagree that this filter is a "better" filter than their standard offerings, but I contend that it is not a REQUIRED filter. Choosing this filter over the others is no different than choosing a "synthetic" over a "dino" lubricant.

Wix, Baldwin, Purolator, etc all make offerings based upon the OEM spec'd criteria for filtration. They take all characteristics into account. And there is NO reason be think that Wix filter 51348 that fits HD motorcycles, is better or worse than other options, just because it also fits Toyotas, Koehlers, Mazdas, John Deeres, etc.

I hope that I've now put to bed the fact that a filter is spec'd upon size, flow, bypass and burst pressures, efficiency, etc as determined by the OEM.

AGAIN, THE OP ASKED IN THE INTITAL POST WHAT MAKES A MOTORCYCLE FILTER DIFFERENT FROM A CAR FILTER?

THE ANSWER IS .....

NOTHING. UNLESS YOU INCLUDE EXORBITANT PRICE.
 
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I still say it's the CHROME.
Say it.
Chrome.....Chrome.....Chrome......
.
.
.
.
55892006_XL1200C-3.JPG


5589Fat_Boy.JPG

.
.
.
And really shiny aluminum stuff is OK, also.
.
.
.
 
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Originally Posted By: dnewton3
OK. Did a little research on the part number you provided.

Here's my synopsis of 63798-99A ...

It's more Harley Davidson marketing at it's finest. Period.

Depending upon what web page you want to believe, it's either a 5um or 10um nominal offering. Further, it's intended to be a one-size fits all replacement, or maybe not. Also, depending on what enthusiast web page you want to follow, the "A" suffix either does or does not mean it's chromed. Even the HD afficianados can't agree on what it is.

http://www.latus-harley-davidson.com/Genuine-Harley-Davidson-Oil-Filters-4.htm

http://www.v-twinforum.com/forums/evolut...il-filters.html

http://xlforum.net/vbportal/forums/showthread.php?threadid=201893

Now, let's agree that Wix and Baldwin are two top contenders for quality filters at a reasonable price. They are not the only vendors, to be sure, but they are very good at what they do. They both offer a few different options for HD motorcycles, depending upon application. Some are chrome, some not. Some flow a bit more than others. Etc, etc. The bottom line is that even these filters have multiple applications; not just HD, but Mazda's, Toyota's, cars, truck, motorcycles, etc. Don't believe me? Look them up at http://www.wixfilters.com and http://www.baldwinfilter.com

What is clear to me is that Harley Davidson has found yet another way to bring the sheep into the fold, and get the cash.

Is the 63798-99A a good filter? Possibly so. But even HD calls it their "SuperPremium" filter. It's meant as an upgrade. It's a feel good option that is not REQUIRED for proper operation of the motorcycle; it's an upgrade.

Here's a direct link to the HD official site:
http://www.harley-davidson.com/gma/gma_p...&bmLocale=en_US

"63798-99A
SuperPremium5™ Oil Filter
Fits all '99-later Twin Cam and Evolution® 1340-equipped models and available as an upgrade for any motorcycle that requires Oil Filter P/N 63796-77A, 63805-80A, 63812-90 or 63813-90.
Chrome
MSRP US $13.95"

Notice that they state " ... an upgrade for any motorcycle that requires ..."
There you have it. It's an upgrade. It's NOT required.

It's no different than choosing a Fram, or a Wix, or an Amsoil filter. There are always different choices for grade and quality. I will not disagree that this filter is a "better" filter than their standard offerings, but I contend that it is not a REQUIRED filter. Choosing this filter over the others is no different than choosing a "synthetic" over a "dino" lubricant.

Wix, Baldwin, Purolator, etc all make offerings based upon the OEM spec'd criteria for filtration. They take all characteristics into account. And there is NO reason be think that Wix filter 51348 that fits HD motorcycles, is better or worse than other options, just because it also fits Toyotas, Koehlers, Mazdas, John Deeres, etc.

I hope that I've now put to bed the fact that a filter is spec'd upon size, flow, bypass and burst pressures, efficiency, etc as determined by the OEM.

AGAIN, THE OP ASKED IN THE INTITAL POST WHAT MAKES A MOTORCYCLE FILTER DIFFERENT FROM A CAR FILTER?

THE ANSWER IS .....

NOTHING. UNLESS YOU INCLUDE EXORBITANT PRICE.



All you have proven is that you know how to use google. And you are another frustrated Harley Basher
 
If this is your "research" then you are simply pulling this all out of your butt. I would have expected something a bit more technical.

This is nothing more than typical frustrated Harley Basher jibberish at it's finest. PERIOD! Your "synopsis" can be found at any Honda forum. Why are you scumming up this forum with nothing more than your trite opinions? If you have some real evidence of why a 5 micron filter should NOT be used when HD spec's it for the TC series engines then let's hear it. Cutting and pasting quotes from advsrtisements and other forums and trying to pass those off as some type of technical proof is simply an insult to the readers of this forum. Sheesh!
smirk2.gif
 
I'm not trying to be rude, I just have the annoying habit of wanting to see proof to reconcile facts in my mind. I love technical data. It's where the shade-tree gear-head meets the degree'd engineer in me.

If you are a degreed engineer......I'm George Washington. Your posts are 100% opinion based on an internet filter application chart where you make wild assumptions about a filter manufacturers product liability. If I made a presentation like this at my job I would be laughed out of Detroit. You offer no technical data regarding how a wix filter matches the 5 micron rating of the HD filter. None. Reason= The Wix filter doesn't match it. Oh sure it will screw onto the filter plate of the Harley. But will the performance match the HD spec. ANSWER: No.

HD specs 91 octane fuel. Will 87 work? Maybe. Will it cause engine damaging detonation? Maybe. Is 87 cheaper? Sure. Same logic applies here. Since you have owned several HD's and "gotten out of them" it is obvious you have some type of axe to grind here. Me I am looking for some type of technical data that will prove to me I can substitute a less expensive filter for the HD ones I use and make an informed decision and maybe save a few bucks and still reap equivalent performance. You arguments while they seem logical are nothing more than opinion. No empirical data based on experience or technical data based on real research just blah, blah blah.

Well, not good enough for me to take a chance on toasting a $4,000 engine for $3-4 savings on a wix filter.

Got data? Let's hear it.
12.gif
 
Well it seems your filter has a nominal 19 micron rating versus the HD on at 5 micron or the evo filter at 10 micron as well as paper media versus synthetic zoom
Part Number: 51348
UPC Number: 765809513488
Principal Application: Various Chrysler/Jeep (82-08), Various GM, Saturn (85-07), Lexus (90-08), Saab (67-08), Suzuki (86-02), Toyota (88-08), Yugo (86-89), Harley-Davidson, Various Lawn&Garden, Farm Equip.
All Applications
Style: Spin-On Lube Filter
Service: Lube
Type: Full Flow
Media: Paper
Height: 3.404
Outer Diameter Top: 2.921
Outer Diameter Bottom: Closed
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes
Beta Ratio: 2/20=21/37
Burst Pressure-PSI: 275
Max Flow Rate: 7-9 GPM
Nominal Micron Rating: 19

Gasket Diameters
Number O.D. I.D. Thk.
Attached 2.734 2.430 0.226





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