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200eazy
07-06-2016, 08:48 AM
I know this is not the correct forum to post this, but being a new member this is the only place i can post. I have a 1990 moto 4 350(yfm350er) and im having trouble finding parts for it. Specifically the muffler and intake boot. Was wondering if any of you guys in here would know what parts will interchange, i can find parts for the big bears and Kodiak, and a few for the moto 4. The only muffler i can find for the moto 4 is 267 bucks, and it supposed to be a stock replacement. I hate to pay that much for something that sounds stock. Also im in need of a good intake boot, that will not melt. I have already put 2 on it and they are melting off. I know it is running lean a little but i cant imagine it is that lean.

DohcBikes
07-06-2016, 08:57 AM
You're going to pay a premium for a good vintage muffler. Believe it or not some people don't like loud exhaust, and a lot of engineering goes into stock exhaust setups.

If you are melting intake boots you have issues. If you "know it is running lean a little" why don't you try to find out why?

200eazy
07-06-2016, 10:41 AM
The leanness is due to the fact that the guy (moron) I got it from put a homemade exhaust on it. It was mostly 2 inch automotive tail pipe with a 2.5 inch truck tip on it. I never thought it would be so lean it would cause that much heat but I guess it did. I've also herd and read online from many places that the after market intake boots are very fragile. It is 2 metal flanges connected in the middle with a thin piece of rubber. I will not waste the money on another one until it has the correct muffler on it, that is why I was wondering if a muffler for a Kodiak, Big Bear, Warrior, etc might work without a whole lot of modification.

DohcBikes
07-07-2016, 12:38 PM
Use ebay to compare pics from other 350 powered yamahas then use your grinder and welder to make the necessary mods.

I hear ya on the intake. On my latest 225dx build, i went ahead and burned all the rubber off and will be tig welding the two aluminum pieces together. If you wanna use your stock airbox you'll have to weld in a spacer as well.

RubberSalt
07-07-2016, 12:40 PM
How big around is the pipe on that? You might be able to slip something on of similar size and weld a bracket or 2 to it to make it bolt up to the frame.

As for the intake boot, one of the guys here, jeswinehart, may be able to reproduce them with much higher quality.

DohcBikes
07-07-2016, 12:45 PM
After some checking on ebay it looks to me like the early warrior mufler brackets are n the same positions, you'd just have to modify the inlet to fit your header.

200eazy
07-11-2016, 12:47 PM
Would it hurt anything to use an all metal intake? I have the parts to do it with but i was concerned about heat transfer from the head damaging the carb.