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FMF SX Power bomb header and jetting

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Hi, I plan on riding this sunday and with my work schedule I will not have time to do any jetting ,that and I don't have any jets.

My ? is will I have to jet the bike when putting on this header when using the same muffler (stock w/ pro billit end cap)witch runs very good w/ the stock header (pilot screw 2 1/2 turns and clip moved down one from stock) :thumbsup:

Looking for more bottom to mid range power on my 04 wr250f

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Will the Power Bomb fit in place of the stock header? I've been thinking of just adding the Power Bomb, but didn't know if it would fit properly or have to be modified to replace the stock header. Please let me know how it goes, fit wise and jet wise. If anyone else has done this, please supply any feedback you may have. Thanks!

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The PB head pipe will NOT fit as is with the stock silencer. You will have to remove the gasket piece at the joint from the stock silencer since the PB head pipe is larger in diameter than the stock head pipe at the joint. You can use aluminum flashing from Home Depot to cut out 2 layers of the aluminum sheet to use as the gasket at the joint - my buddy and I both use this setup with our PB head pipe and the stock silencer. If you're really concerned with any leaks at the joint, you can use red heat resistance silicone to fill in any holes at the joint, we don't bother with it and it works fine. Here is a picture of the aluminum flashing that I use (it's really cheap too) :thumbsup:

DSC00031.JPG

The idea is to make something like this:

DSC00194.JPG

I also use the flashing along with 2 sided tape and some zip-ties for my upper frame guards to match the Works Connection lower guards. They've been on for 2 years and I haven't had to replace them yet :devil:

DSC00034.JPG

WorksConnection_left_frame_guard.jpg

WorksConnection_right_frame_guard.jpg

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Gary,

Try using a 12 teeth CS to help with low end snap, they're cheap ($7 to $15), it will give you much better snap and it's great for the woods lugging too. I've been running with a 12 teeth CS for over 2 years - no problem with wear anywhere... :thumbsup:

For my 02, my avNow does wonders at lower RPM, I had the original PowerNow at first which helped the low end some but the improvement was not as noticeable as my 3 plated avNow (the link for the avNow is in my sig, the link may be locked if too many people are accessing my site, it's a Verizon thing, so just come back and try the link later). :devil:

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If you're already jetted correctly for the stock silencer, you don't need to do any significant jetting changes based on my experience - maybe tweak the fuel screw a little but I didn't have to mess with anything, others may vary... :thumbsup:

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Help, this flashing idea is not working. Way to much space and now I can't use the stock gasket ( screwed it up taking it out) or header this weekend Help!

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Help, this flashing idea is not working. Way to much space and now I can't use the stock gasket ( screwed it up taking it out) or header this weekend Help!

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Help, this flashing idea is not working. Way to much space and now I can't use the stock gasket ( screwed it up taking it out) or header this weekend Help!

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Gary,

I just did this a couple weeks ago and had to use 3 layers of flashing to get a tight seal. First slip the muffler on the mounted PB header and scribe where the muffler end overlaps the header. Take the muffler back off then measure the distance from the scribe mark to the end of the header. This is the width you need to cut the flashing. Wrap the flashing pieces around the header where the muffler will overlap it and cut to length so the ends fit snugly. Remember each layer will be a little longer to compensate for the one underneath it.

Now take 2 hose clamps and clamp the cut pieces of flashing onto your PB header (aligning the edges with the scibe mark). Start slipping the muffler on up to the first hose clamp. Remove that hose clamp and tighten it on the header just behind the flashing. This will keep the flashing from sliding forward as you push the muffler on and remove the next hose clamp.

This worked out nicely for me. The fit was tight enough that I didn't need to use any red RTV silicone.

Now go out and enjoy the new low end grunt. :thumbsup:

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Hi, I plan on riding this sunday and with my work schedule I will not have time to do any jetting ,that and I don't have any jets.

My ? is will I have to jet the bike when putting on this header when using the same muffler (stock w/ pro billit end cap)witch runs very good w/ the stock header (pilot screw 2 1/2 turns and clip moved down one from stock) :thumbsup:

Looking for more bottom to mid range power on my 04 wr250f

Gary, I missed the part about your silencer being for a stock wr250f. The picture above is of my 02 wr250f silencer & the PB head pipe, the flashing is only good for the yz250f silencer and the PB head pipe - the wr's silencer has a larger diameter than the yzf's silencer at the joint. I had to fabricate the mid joint piece in the picture above to fit the wr's stock silencer. Sounds like you've found the wr426f or wr450f gasket to work well for you, that's good to know. :devil::awww:

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