2009 WR450F setup / observations

I have an 08, same bike as the 09. Same basic mods you have, fmf pipe/header, ais removed, and all the free mods. The exhaust made an amazing difference in performance. You should remove the snorkel from the intake if you haven't done that yet. It's under the seat by the battery. The suspension was dangerous stock. Why they sell a bike set up so soft amazes me. I had ESP revalve/spring for my weight/skill and desert riding and it transformed the bike. Lots of companies out there that can do similar work. I don't see the point in changing to yz suspension. My sons revalved yz450 suspension works no better than mine now.

we actually didn't do the snorkel, based on this comment from the FAQ (http://www.thumperfaq.com/airbox.htm):

"The snorkel can be easily removed to improve airflow but the performance gain is minimal as the airbox is still quite restricted by the battery. "

did you remove the battery as well, and hack the airbox or just pull the snorkel?

The snorkle has 2 holes in it to let air in. With it removed you probably get double the area to pass air. With that open and the inlet thru the side panel there is plenty of air flow. It pulls right out so I see no reason not to take advantage of it. Honestly, I think the whole issue how much air flow is required is overblown (no pun intended). With the snorkle removed there is a plenty big hole for air flow. I can't see any increase in engine performance coming from trying to cut out part of the battery tray. My bike runs real strong and will rev to the limiter. By the way, that snorkle is there for reduce intake noise as part of the mods to get it to pass EPA requirements to get a green sticker.

By the way, that snorkle is there for reduce intake noise as part of the mods to get it to pass EPA requirements to get a green sticker.

that is the other reason i left it on, because i heard the rangers are checking these now.

i need to get some hours on the bike as is before i change anything else.

The snorkle has 2 holes in it to let air in. With it removed you probably get double the area to pass air. With that open and the inlet thru the side panel there is plenty of air flow. It pulls right out so I see no reason not to take advantage of it. Honestly, I think the whole issue how much air flow is required is overblown (no pun intended). With the snorkle removed there is a plenty big hole for air flow. I can't see any increase in engine performance coming from trying to cut out part of the battery tray. My bike runs real strong and will rev to the limiter. By the way, that snorkle is there for reduce intake noise as part of the mods to get it to pass EPA requirements to get a green sticker.

In my very unscientific butt dyno I would say I gained a bit of midrange and overev when I cut back my battery tray for increased airflow. This was after installing my Ebatt lithium which leaves so much room in the battery tray. It also increased airbox noise. I haven't been sound tested since I've done the mod so don't know if it's an issue but you can definately hear it.

In my very unscientific butt dyno I would say I gained a bit of midrange and overev when I cut back my battery tray for increased airflow. This was after installing my Ebatt lithium which leaves so much room in the battery tray. It also increased airbox noise. I haven't been sound tested since I've done the mod so don't know if it's an issue but you can definately hear it.

tribal, does that ebatt have enough power to support all the electronics on the newer bikes? lights, computer, electric start, etc. ?

tribal, does that ebatt have enough power to support all the electronics on the newer bikes? lights, computer, electric start, etc. ?

As good or a little better than stock.

As good or a little better than stock.

did you strap it down in there or does it come with a custom mounting system?

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