2005 YZ450F stock gearing and mods Q's

Hello fellas i just got a new to me 05 450f a couple days ago and since then i have been on TT searching like mad for upgrades and mods to get it running like i want to so i have a few questions that id like to ask as im having trouble finding info

1. Im the manual it states that secondary gearing is 14/51. Does this mean it has those sprockets on from stock?(currently 14/48 on there now) primary gearing is inside the box i believe so that must be it right? Every post I have seen says standard gearing is 14/48 or 49 so want to make sure. Im thinking 13/51 or 13/52. I do mainly all sorts of trails and a little bit of motocross.

2. Since i cant get the GYTR +9oz flywheel for my bike for under $100 anymore ($260 from Australian Yamaha) im looking at getting either the steahly 10oz or trailtech 10oz complete flywheels. Any one recommend NOT getting them? Will these with my lower gearing make the bike sort of slow? or just make it lug more but still have the same power

3. Unabiker radiator guards/braces are the ones i am set on as they incorporate guards and braces in 1. Anyone recommend me NOT to get them or anything else better? i want both fall protection and front on impact protection. Also i have read numerous posts with having to bend/cut/mod plastics etc and generally having a hard time fitting them. My radiators are straight as new so im hoping they will be fine

Sorry for the abundance of questions.. Just want to buy right the first time not twice before i get the right thing


1. The '05 was different than any previous or subsequent YZ450 in that it was the only 4 speed model made with the higher 2.65 primary drive ratio. The '03 and '04 had a 2.82 ratio, which meant that an '04 with a 14/48 was geared almost exactly the same as an '05 with a 14/51. The '06 and later models have the same primary ratio, and are delivered with a 13/49. Yours is geared 3 teeth higher than stock (the same as going to a one tooth larger front sprocket).

2. The 10 ounce should be OK.

Thanks for the info Gray, i thought there was something weird about the gearing being a 51 in the rear from factory but now i know why.

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