help installing 426 spark arrestor

I just bought an 02 426 and absolutely LOVE IT. The guy who sold it gave me an un opened spark arrestor and I am not sure how to get the rivets out of the stock pipe...can someone please give me full directions on this process? Thanks guys

Just drill out the exsisting rivets and pull the insert out. Place the spark arrestor over the interior pipe (you may need to modify the screen) and re-rivit the end cap back on. Make sure not to use too large of a drill bit. It should only be as large as the new rivet diameter.

So i drill THROUGH the rivets? If i drill through them what do i replace them with?

Take a drill just smaller than the head of the rivet, but larger than the shank of the rivet, and drill straight down into the head, as well centered as possible. About the time the drill reaches the level where the actual muffler skin is, the rivet head will spin free of the rivet shank. You can the punch the remainder of the rivet inward and retrieve it once the end cap is off.

You just drill them out...I think a 13/64ths bit will do the trick. Then you have to install new rivets when you put it back together so you will need to buy/borrow a rivet gun. Might as well check to see if you need to repack your muffler while you are at it.

What type of spark arrestor is it...ProMoto Billet?

Yes, it is a promoto billet!

Yes, it is a promoto billet!

That's what I use...they look good, work good, and sound good. I even leave mine in when racing on a closed course where they are not required.

So i drill THROUGH the rivets? If i drill through them what do i replace them with?
Not through them, only down to the point where the heads come off, then you punch out the rest of it. Replace them with ordinary blind rivets ("pop" rivets). Stainless rivets will last the longest.

You can also set it up with threaded oval or round head screws and cage nuts to make future service easier.

Can I re-use the rivets, or is that a stupid question? haha sorry I am relatively new to riding!

No, drilling the head off tends to be a bit destructive. Rivets are, by their nature, single use items. They're half destroyed in the installation, and they can only be removed by cutting or drilling them apart.

They are very cheap and easy to find, though.

Thanks for all your help!!! What size rivets should i be getting?

Can I re-use the rivets, or is that a stupid question? haha sorry I am relatively new to riding!

Don't sweat it...there's no such thing as a stupid question about bikes...except for the one you're afraid to ask. By the way, it is normal for your header to glow red if you fire your bike up in the dark, and if you're wondering what kind of oil to use just do a search and you will find about 100 threads on the Great Oil Debate. Good luck with your spark arrestor!

What size rivets should i be getting?
The size that best fits the holes in the end cap.

i did the promoto billet and the only things i regretted were not repacking the mufffler while i was at it and replacing the old rivets with new ones. In the directions it said you could use screws instead, im wishing i would have gone that route. I have a bbr exhaust on my other bike and all that take the endcap off is 3 allen screws which makes it real nice

How do you repack the muffler? :thumbsup:

use the search feature at the top of the forums. youll get all the info you can possible need. im about to do my 250f this weekend and i got all the info i needed just from searching.

use the search feature at the top of the forums. youll get all the info you can possible need. im about to do my 250f this weekend and i got all the info i needed just from searching.

Did it say anywhere to NOT wear fleece while removing the old fiberglass packing? I learned that the hard way :thumbsup::devil:

good to know. i had fleece on today when i took off my endcap to look at the condition of the packing. good thing i stopped just short of pulling it out.

Can i leave the muffler on the bike or is it easier to remove it?

Removing the muffler or "can" works best for me. The rivets on the inside are difficult to get at with the muffler still on the bike, assuming you still have the rear fender mounted. Just remember to take your time while drilling the old rivets so that you don't accidentally make the rivet holes in the muffler any larger. As far as how to repack the muffler goes, you should get detailed instructions either in or on the packing container. Be sure that you get the packing made for 4-strokes and not for the 2-strokes. As I am not sure as to how the promoto end caps seal to the muffler, it may be wise to pick up some high-temp silicone to use as well.:thumbsup:

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