YZ air filter cage
Posted March 15, 2001 - 10:26 PM
When I returned to the track after these modifications, I noticed an increase in overall throttle response. The biggest increase came in the lower rpm range but it felt better all the way to the rev limiter.
You could probably cut the mesh out of the stock filter cage. I did that first cause I am too cheap to buy a new filter cage but it was hard to trim close to the plastic. After poking my fingers and making them bleed, I bought a YZ cage!!
Posted March 16, 2001 - 07:49 AM
Posted March 16, 2001 - 10:13 PM
I've been running yz cage on my 99 400 and 2000 426 with no problem, on my 2001 I've noticed a darker spot last month, it's not th oil cause I don't put any for ice racing, no fire so far...
Posted March 16, 2001 - 06:57 PM
Posted March 17, 2001 - 07:46 AM
I like how the screen adds a bit of insurance, keeping any big chunks out that get by or through the air filter somehow.
Posted March 17, 2001 - 08:28 PM
I'd like to see some data on the flow also, it feels crisper but without riding one with and without the screen back to back it is impossible to be sure.
Posted March 18, 2001 - 09:53 AM
I ran 6 tests on each setup at 10" water, and 15" water (total of 12 passes on each setup) and corrected for flow bench temps and atmoshperic.
The Twin Air showed a consistent mean of 1/2 of 1 cfm advantage, and the setup with no air filter showed a mean 1.25 cfm over the stock air filter, .75 cfm over the Twin Air. While my test setup is far from the definitive word on this if you guys can find horsepower in those differences you are WAY BETTER than me at this.
Just for fun I ran the same setup with no air box or boot connected and not surprisingly it flows less than the OEM filter/airbox setup. There are some gains to be had be modifying the bellmouth of the carb or the boot transition to thwe carb. Whether or not this will translate to useable gains remains to be seen.
Your mileage may vary
[This message has been edited by Rich Rohrich (edited 03-18-2001).]
Posted March 18, 2001 - 01:53 PM
Posted March 18, 2001 - 06:34 PM
like a kid again!
01 TT-R125L (my son's)
74 Hodaka Super Combat
[This message has been edited by dirtdad (edited 03-18-2001).]
Posted March 19, 2001 - 07:57 PM
Originally posted by F-Pilot:
BIG CHUNKS? Through a foam filter????
Posted March 19, 2001 - 09:34 PM
I didn't understand the conclusion to your results.
You listed an "advantage" in CFM but then implied that it would not result in more HP.
What am I not getting?
Posted March 20, 2001 - 01:38 PM
I am thinking about putting the screened cage back in now, sure don't want to watch 5g's burn to the ground!
Posted March 20, 2001 - 03:39 PM
In my original post I simply said that I observed better throttle response. I NEVER said anything about increased overall horsepower.
I have been riding YZ-F's since the end of 97 with a YZ filter cage and have not even singed a filter. I am pretty anal about my jetting and that may contribute to why my bikes have never backfired.
Posted March 20, 2001 - 05:06 PM
Posted March 20, 2001 - 08:07 PM
Posted March 21, 2001 - 06:02 AM
Posted March 21, 2001 - 06:43 AM
I have never done any flow test or, for that matter, any other kind of test except the "seat of the pants" test. I know I'm getting better throttle response and even if I did gain a horsepower or two I would never even know!! This bike rips.
I have a Stroker rev exhaust system on the bike and I run either Union 76 Red or VP Red race fuels. My jetting is as follows:
Needle------3rd (1 leaner than stock)
Fuel Screw--1.5 turn out
This jetting works very well for Southern California tracks which range from 100'-3500' elevation. I turn the fuel screw out .5 turns at the lower elevations and in .5 turns at the upper elevations.
Snake pit oct 30th by The Anvil
Yamaha YZ450F 2017 by Chris.GVS
Megabomb Fitment by 288yz450