What did you do to your FJR today?

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SkooterG

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Air filters are, for most people, the most overly completed service.  Unless you typically ride in a particularly dusty area, it is sufficient to use compressed air to blow out the loose dust. Reverse the installation direction and carry on.  50,000 miles or more shouldn't be an issue.  The filter actually becomes more efficient as it gets "plugged".  


I am having a tough time digesting this.  Got any links to a reputed source that says the dirtier an air filter the better?  I replace mine at the recommended interval of 12k.  It is inexpensive piece of mind.  I recently took one out of a used bike I bought that has 56k miles and it was black.  I have no idea if it is the original or not, but I was glad to get it out of there.

 

Ignacio

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I am having a tough time digesting this.  Got any links to a reputed source that says the dirtier an air filter the better? 
Resisting COVID patient analogy of the more efficient their lungs becomes the less they can breath.

....oh, I guess I didn't resist actually.  And I call hooey on the claim.

 

RossKean

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I am having a tough time digesting this.  Got any links to a reputed source that says the dirtier an air filter the better?  I replace mine at the recommended interval of 12k. 
Owner's manual says clean OR replace at the specified intervals.

If a filter was uniformly dirty end-to-end, there is no doubt I would replace it but in my riding region, this is never the case.  Most of the dirt blows out with compressed air, as per the owner's manual, and I don't worry about continuing to use it for far more than 12,000 miles.

As long as "enough" air goes through the filter to keep the engine happy, the filter will actually stops a higher proportion of dirt (down to smaller particle sizes) as the openings become occluded with dirt.  Of course, there is greater resistance to flow and eventually the engine will not be getting enough air.  You will notice that typically one end of the filter is much worse than the other.  This tells me that flow restriction is not yet severe and air still passes easily on a direct path - as it became restricted to flow, you would see more dirt on the other end as well.

As you say, an air filter isn't that expensive and it isn't particularly difficult to change.  Just saying it probably doesn't need to be changed as often if the environment is not especially dusty or high in pollen or other particulates.

 

RossKean

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I never said the dirtier the filter the better.  I merely indicated that it becomes a more efficient filter (i.e. smaller particles) as it becomes partially plugged - the holes get effectively smaller.  Less dirt, not more, gets through.   At the same time, a greater pressure differential across the filter medium is required to maintain the same flow rate.   Obviously, at some point, the filter will not allow sufficient air to pass and the filter has to be cleaned or replaced.

Not advocating that it is preferable to use a dirty filter, just that it probably does not NEED to be changed as often as some people do.  (In agreement with owner's manual - clean or replace).  Ever see an FJR run rich because of a partially plugged air filter?

There are dozens thousands of scientific papers out there on flow and penetration of filter media as a function of loading - pretty basic stuff and applies to everything from respirators to automotive filters to building HVAC systems to clean laboratory HEPA systems.  Resistance to flow goes up and retention (%) of finer particles also goes up (assuming the filter medium is not physically damaged).  Filter media replacement is required when pressure drop across the filter becomes too great; not because dirt is coming through.

Depending upon the nature of the material on the filter, humidity can also have a large effect - hydrophilic materials can absorb moisture and swell causing greater resistance to flow.

And I call hooey on the claim.
Suit yourself.

 

RossKean

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Seal-Mated the left side fork seal for the second time this year.  Very slow leak.  It is difficult to do a really good job on the seals with the forks on the bike.  Sometime in the next week or so, I am going to change fork oil and give the seals a really good cleaning at the same time with the forks off the bike.  Might be time to change seals (and bushings) but I think I will try to get another year out of them.  Quite a few miles since the Traxxion AK20 setup was done...

 

RossKean

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check for tiny nicks/scratches feeling with fingernail then polish out. That will most likely fix it and save you hours of downtime and $$
Good advice...

I didn't see anything when I did the Seal Mate yesterday.  Since I am changing the fork oil in the next week or so, I'll have a really good look at the fork tubes while the forks are off the bike.

It is probably time to replace the seals and bushings but I think I will wait if I can.

 

RaiderBill

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Rode to the grocery store for the wife. It was 41 degrees out but at least I got to ride. I have sure got my money out of my firstgear heated jacket. 

 

sullivan

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39 and rain today on the commute.  A few coworkers gave me "the look" when I said I wouldn't melt in the rain.  Snow 5 miles away, but no matter.  

PipeWerx slip-ons are thumbs up, after having them for a month.  Carbon Fibre looks great with the gray of my 19A

 

fjrob1300

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Last year on this day I was in 6 inches of snow out deer hunting. -2 C. Today , at the same location I was riding my 2003 FJR.  Love the weather 20C and sunny

 

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