No air-filter? Great job dealership...

pcarnut · Apr 18, 2013

yamafitter said:
Yroundrdn said:

Might as well go with K&N I guess.

Click to expand...

You may want to rethink the K&N. If you are not very careful it is easy to over-oil the filter and then that oil gets pulled off the filter and on to the throttle body butterfly valves where it can create issues. The stock filter isn't that bad for airflow and any performance gains from using a K&N are not noticeable IMHO. Most folks do not clean & oil a K&N properly and end up with a messy and sticky airbox plus other possible issues. I had a K&N but took it out and went back to stock since it made the maintenance easier.

I avoid K&N due to their allowing more particles through the filtering media- cheesecloth. From my dirt riding days I'm sold on Uni foam filters. I've looked at reports comparing K&N, foam and stock filters. The foam did as well as stock or better and it's cleanable/reusable. You can usually get them at your Yamaha dealer, at least I did.

Queensland Ken · Apr 18, 2013

"The K&N Filtercharger is designed to increase engine performance in both horsepower and throttle response by reducing air flow restriction."

Didn't someone on this forum get their bike dynoed before and after the K&N ???

I think it made no difference.

Service wise, I like the K&N better.

With the stock filter, I had particles in the air box, with the K&N none.

I use a bit of Vaseline in the air box, before and after the filter, to trap any bits that shouldn't be there, the K&N works well.

Neil San Diego · Apr 18, 2013

Yroundrdn said:
...Obviously I'll be changing the oil and filter next, no telling what they screwed up there....

Sorry to hear about that. But unfortunately, I think you're going to find that most of the dealerships down here are pretty much the same.

One of our members in San Diego area had a local dealership replace the rear brake shoes, only to find out later at a tech day that they had installed them backwards - the metal backside against the rotor. I think most of these mechanics were delivering pizza a week or two ago...

ionbeam · Apr 18, 2013

Queensland Ken said:
"The K&N Filtercharger is designed to increase engine performance in both horsepower and throttle response by reducing air flow restriction."

Click to expand...

Didn't someone on this forum get their bike dynoed before and after the K&N ???

I think it made no difference.

The quote was directly from K&N's web site. I did mention that they may be trying to sell something...

Motorcycle engines, well power sport engines including snow sleds and boats are highly developed engines; much more developed than most car and light trucks though the gap is closing. My big lazy Chubby V8 LT1 Corvette engined car had lots and lots of room for easy improvements. I added a K&N high flow filter and only saw very small gains at the drag strip. I added a high flow Borla exhaust and saw a significant performance improvement. Putting the stock air box and stock air filter back in reduced performance so there was some gain from the K&N. (The air box and K&N went right back in.)

A modern, late model performance motorcycle's engine is highly designed for good volumetric efficiency. Every part of the intake and exhaust has been painstakingly designed against the vehicles performance goals. There is not much that can be done to step-up these engines with simple add-on parts. The power curve can be reshaped but it detracts from the overall design goals. Most high performance engines need significant work to make them noticeably better such as cams, heads and big bore kits.

In the world of easy add-on power adders the FJR is at a disadvantage because the spark timing is not accessible. This prevents power adders like a Power Commander from actually being much of a power adder. A high flow air filter won't do much for the FJR except let in too much dirt unless it was over oiled, then it will filter better but streams oil into the intake.