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Exhaust backfiring

Discussion in General Scooter Discussion started by JoJo, 15 May 2013
JoJo#1
Put the new Exhaust on today, I dont like how loud it is but thats something i'll get used to unless I can get a Silencer for it, but its backfiring, there was air coming from both ends of the Pipe so I took it off and used Exhaust Paste on all the connection parts (pipe, gasket etc) and thats all fine now, but the backfiring is really doing my head in, any way to solve this?

IMG_3266.JPGIMG_3267.JPG
supraking#2
does it do it when its cold. or after its warmed up, it might be some unburnt fuel in there.
JoJo#3
Urmm... when I let off the acceleration so when its warm.
supraking#4
yup running rich on overrun, did u change the jets when you swapped the exhaust?
JoJo#5
No as I didnt get told to, I bought the Exhaust from the same people I got the Bike from, the main suppliers, and they didnt mention anything, just said to put it on..... what do you suggest doing?
supraking#6
erm, personally not much im new to all this so jsut going off what ive picked up over the past week. and what my car does (burbles on over run its that rich)

but im sure one of this knowledgable lot will help you out better
JoJo#7
haha thanks, do Sports Exhausts make the Bike slower? just read that they make the Bike louder and slower, think I might need to go out for a run and see the speed I get to, usually gets to 50 easy, if thats the case and its still backfiring then I might sell it and get another normal stock one like the one that came with it (but it was blowing hence the new Exhaust)
supraking#8
i think to complement the new pipe you need to uprate the rest, jets/clutch springs/rollers

but again this could be hear say :)
scootzmadness#9
rejet it
JoJo#10
I have no clue about the Jets etc, are there any tutorials online I can look at, or will it be better taking it to my local Bike Shop? as if the Jets need messing with then I can buy a new/smaller Air Box aswell so it can be done altogether.
scootzmadness#11
if your not confident enough to do it take it bike shop but they'll charge you over the odds for labour, been there done that. start with a big jet and work your way down until its perfect, that's the way ive always done it.
this should sort of help -
YouTube video
JoJo#12
Yeah i've seen that Video before, YouTube has been my best friend lately,
where do I get these Jets from exactly?
scootzmadness#13
ebay, bike shop, pedparts loads of places to get them from
JoJo#14
Ok thanks alot, i'll take it down to the Bike Shop and have them check over it and see what they suggest, im not sure whether it was because there was no Gasket between the Engine and the Pipe, there wasnt one on the original Exhaust, I used the Exhaust Paste around the Pipe opening though, the bolts are tight and obv got the Exhaust Paste aswell and cant seem to feel any air coming from that part, or where the Pipe goes to the Exhaust itself, will see what they say anyway.
scootzmadness#15
get a gasket inbetween there ! gasket paste on its own simply wont do the job
JoJo#16
Just emailed the suppliers to see if the one I seen it the correct one, £7 something...
scootzmadness#17
for one jet ?
JoJo#18
For the Gasket.
scootzmadness#19
ohh, get some gasket paper, can get a big sheet for like £5, make your own, I make my own exhaust gaskets, trans cover gaskets and occasionally headgaskets, its not hard and youll be able to make more out of one sheet if you ever needed too
JoJo#20

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