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so fmf pipe doesnt match with PC silencer

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title says it. 1999 yz125. that im currently getting up and going. i bought a fmf sst pipe and it fits perfect on the bike but it doesn't fit up with the pro circuit silencer. Can i bend it to fit or cut it, or...? anyone had this problem? i would use the stock parts but i don't have them.

Thanks for the help:)

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the fmf SST requires you use the SST mufflers(2 options I believe). end section if different on the SST pipes.

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Take out the two mounting bolts for the pipe and then try and align it up with only the springs holding the pipe on. From here you can see what kind of alterations you'll have to make in order for it to mount to the frame. You could cut out a little tab of metal to use as an extension for the two tabs on the pipe, so that it lines up.

This would work for the silencer as well, which might be easier. Leave the mounting bolts for the silencer out and attach it to the flange, see how far away the holes are from lining up and make metal tabs to compensate.

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I'd be careful with that SST pipe. It's a jetting nightmare, it acts like its rich even though its really lean and then you end up burning a hole in your piston.

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Acronym: FMF

Meaning: ****ing Mother ****ers

Motto: Because using the word "****" only once when describing them just doesn't convey how ****ed up those ****ing mother****ers are...

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thanks ill try and fab up some brackets or something....bend it maybe lol. thanks and the only reason i bought that pipe cause it was 40 bucks and shiny

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hey their, i just came across this post, i know its from 2010, but i am currently having the same issue with my rm 125. did you end up finding a way to fab up that set up? i was thinking of just cutting or grinding down that tiny peace at the part of the silencer where it stops it from going any further into the sst. im about half an inch away from the mounting bracket for the pc silencer. any help/ input would be great. cheers

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I'd be careful with that SST pipe. It's a jetting nightmare, it acts like its rich even though its really lean and then you end up burning a hole in your piston.

Agreed, its a pos, I would rather run a dented stock pipe over a sst. Put one on a ktm 144 for a girl i knew, jetting it was a nightmare.

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on my converted RMYZ I have to tweak almost all pipe or silencers to make a fit possible. I ad half an inch of tubing to the pipe to make a decent fit.

the problem i have , is its actully to long not short. its missing the mounting bracket by half an inch so i was thinking of grinding down the silencer stopper to slide more into the champer pipe this way i dont have to cut the actual silencer shorter then what it already is. plus i dont want to start sawing away on a bran new silencer. but i wasnt sure if it would work.

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so basically i did have to cut some of the silencer off, about 3/4s of an inch off. i had no choice the pc silencer i guess is just not designed for the fmf sst but it did work out good. my jetting seems to be spot on, clip is moved up one notch up with bigger main and pilot jet from before tho, but that was a whole differnt carby issue. but i do like this sst pc shorty combo. powerband has completely changed big time. way more snappier much better throttle response on the mid range, so far i am liking it. i have no sploging of bogging at all.

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