RMK800

What did you do to your YZ450FX today?

653 posts in this topic

Anyone make changes to the stock 14/51 gearing on the 450FX? I tried a 48 in the rear makes the bike a little fast in 2nd thinking of going to a 49? my reasoning is that 2 seems to low and 3rd a little high for tighter woods.

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Anyone make changes to the stock 14/51 gearing on the 450FX? I tried a 48 in the rear makes the bike a little fast in 2nd thinking of going to a 49? my reasoning is that 2 seems to low and 3rd a little high for tighter woods.

Stock is not 14/51. The stock is 13/50. The gearing you have is closer to street use then slower terrain riding. A lot of woods riders go to 13/51 or 13/52. Edited by RMK800

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I am running 13/50 and it feels fine for everything but come-to-a-stop type trails.

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I was also thinking of going to a 52 in the rear. First is low but not low enough for really technical trails.

Also added a gytr fan for the same reason, I'm stunned at how often it comes on. Its a really sweet yamaha accessory, only runs when the bike is hot. Had to do some surgery to the rad braces, but everything is happy now.

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Changed all .69 quarts of oil.

 

Tried to wrap my head around what it will take to put in the Acerbis 2.9 tank. I failed.

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Changed all .69 quarts of oil.

Tried to wrap my head around what it will take to put in the Acerbis 2.9 tank. I failed.

I think Steve has the best option for larger tank on our bikes.

What speedo did you add to yours?

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Acerbis 2.9 gallon tank 1. 2. 3.

1. Remove sub frame & electrical crap from rear fender.

2. Install new Acerbis tank.

3. Buy small Anti Gravity battery make battery box, the rest is self explanatory.

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I think Steve has the best option for larger tank on our bikes.

What speedo did you add to yours?

 

 

The small Trail Tech; Endurance II

20160730_104823_zpscy1rmnj9.jpg

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Acerbis 2.9 gallon tank 1. 2. 3.

1. Remove sub frame & electrical crap from rear fender.

2. Install new Acerbis tank.

3. Buy small Anti Gravity battery make battery box, the rest is self explanatory.

 

You should write instruction manuals

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I bought a fmf exhaust. Any benefit from this? Will I have to program the computer or anything?

 

It will help, but it is not required.

The stock exhaust has a slightly smaller header and exhaust exit size, so your back pressure will go down, but your pulse frequency will go up.

The GYTR tuner is ridiculously easy to program (but not intuitive to use).

 

What area do you live in.

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I bought a fmf exhaust. Any benefit from this? Will I have to program the computer or anything?

It looks pretty. Pipes don't generally change much in jetting and or timing. Play with the tuner on the timing the bike will be much more peppy with +'s on the timing or more tamed with 0's or -'s. The fuel is less noticeable. I can text you my map I'm running. I haven't found any rights or wrongs it's just what you like.

Edited by stevethe

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It will help, but it is not required.

The stock exhaust has a slightly smaller header and exhaust exit size, so your back pressure will go down, but your pulse frequency will go up.

The GYTR tuner is ridiculously easy to program (but not intuitive to use).

What area do you live in.

I live in Apple valley.

When you say the pulse frequency will go up, I don't understand this completely.

Are you saying the engine will be slightly less smooth?

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When you say the pulse frequency will go up, I don't understand this completely.

 

 

Neither does he. 

 

Don't worry about it.  Besides the "pretty" factor that Steve mentioned, it may weigh slightly less.  Other than that, aftermarket exhausts tend to have an outlet at the muffler that's the size of the muffler core, where the stock pipes often use a slightly restricted outlet to help with sound level compliance.  Opening that up a little can improve top end...slightly.

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