home made pipe shorter than shorty

[kawaguy]

hi there guys, is it a good idea to make a silencer for a 1999 kx125 shorter than an fmf shorty, my friend has an 1999 yz 125 and he made a silencer just above half the size of an fmf shorty, it actually went suprisingly well, it was loud but you could feel a difference to the bottom and lower mid range punch, he rode 28 hours on the engine with that pipe on and it didnt suffer a bit, no detonation, the piston crown looked exactly the same as all his other worn pistons, his bike is completely stock except for his home made shorty, maybe it was just his luck that nothing went wrong, if something did go wrong what would go, i would like to here your guys opinions on this and maybe from eric and rich if they have time.............................. and could someone please explain properly what bleed down characteristics of a pipe means. CHEERS

 

[crazy4nitro]

I think you shouldnt jack with that idea. FMF spent alot of money (I would imagine)researching and testing the product they sell.Louder does not mean faster or more power,besides why annoy people with the noise and get thrown out of the riding area..? If your riding on a moto-x track you might consider adding a few teeth to the rear sprocket,I have never in my 15 years of riding ever found 6th gear wound out on a straight. just something to think about,you asked for opinions.

Crazy

 

[bclapham]

it probably made a nice bottom end hit, which would give the impression of the engine having more power; however, shortening the length like that would ruin the top end power and overrev so the engine might sign off really quick- this is where the 125 makes most of its useable power, so IMO its a bad idea.