Derestricting the Kymco Super 8 4T?

[art]

you need to do your plug chops to be sure you are not running to lean.the more mods you do the bigger the jets you need,if you run too lean it can damage your motor!

[Super8504T]

I wondered if any of you could tell me if the exhaust has a restriction in it here at the mount:

It is welded on and it look to be restricting the flow. I dont know whether you can see if very well (camera  )

When I got it it had a sticker on it but I ripped it off not reading it It said something along the lines of.. "WARNING: The exhaust restriction had been removed" Or somthing like that I can't remember.

But I just wondered if this was a restriction, surely they would have removed it if they put that sticker on it  

[Luke.]

of it's a kymco super 8 4t, is it a plate?

[Luke.]

if*

[Super8504T]

It's from my new Leo Vince exhaust.. I dont know whether it is a restricton or not

I need a bit of help.. I've just got it fitted and it sounds great! It really does!! But theres just one query I have.. it backfire's with a tiny flame out the end of the exhaust upon deceleration. Is this normal for the exhaust? Or is something not right?? Does anybody know 

[Luke.]

oh, it'll be derestricted already, what size jets do you have? i have a friend who's exhaust does that but it's pretty old

[Super8504T]

I've not upjetted yet still standard 80. It will be done next week. Is that the problem do you think? I have a 82.5 jet and a 95 jet.

[Luke.]

that would be my guess, have you done the variator yet?
it's probably something to do with not enough fuel getting through

[Super8504T]

Yeah I've done the variator now and that has made the biggest difference so far if ur looking to get a bit more speed I'd recommend it: http://www.adrenalin-pedstop.co.uk/p/POLINI-VARIATOR-SPEED-CONTROL--2992.aspx

But yeah I think that maybe the problem my engine running to lean. I will turn the idle mixture screw tomorrow and try to make the mixture more rich because apparently the mixture is too lean and letting in too much air and so that's why it backfires.

[Luke.]

ah thanks
what is the acceleration & speed difference like?

and are you running on unleaded or super unleaded?

[Super8504T]

The variator came with 6.9g rollers which are no good for acceleration so I've ordered 5.6g so I'll let you knowwhat their like. But at the moment with the standard 6.9g rollers acceleraton is not good at all.. really.. wen you hit 31mph.. the powerbnd kicks in and wisks you up to 40mph quite quickly. Mine sticks at 40mph up a hill gradient.. up really steep hills it sticks at 30mph.. but lighter rollers are needed to get better accleration.. but the top end is great.. I get 70km/h - 45mph on a straight flat at the tops. Just a bigger jet thats needed now to get even better speed 

I used super unleaded a few days ago in the hope that it would clean my engine out a bit.. it probably has.. it feels a bit more smoother.. but its no different performance wise.. I'm using normal unleaded again now.. I will put super unleaded in every few weeks or so I think.

[zombie]

Its real hard to tell from the pict, but is the end of the pipe the same size as the rest of it? It looks like a cone in the end there. You can use a dremel tool to grind some of the material away if you need to. Also I run ONLY high test fuel, and would recommend the same for you. The backfire is due to fuel in the pipe igniting, and is quite normal for any four stroke engine. Last but not least you HAVE to rely on plug chops to set the jetting. I would certainly go up. Try the 95 first, and you can always go back if needed.

[Super8504T]

Yeah it is a funnel cone shape. It is spot welded onto the side body of the exhaut pipe. Will it not just chisel out?

[Super8504T]

Is the backfire really normal? It says in the manual that if it backfires on deceleration then its because the engine is too lean which I've heard isnt good. I've tried adjusting the idle mixture screw, I turned it clockwise to richen the mixture and the idle speed increased which it is supposed to but it still backfire from time to time, its just when you have been travelling at 30-40mph and yu let you of the throttle quickly it backfires. 

[alchemy67]

Yeah I've done the variator now and that has made the biggest difference so far if ur looking to get a bit more speed I'd recommend it: http://www.adrenalin-pedstop.co.uk/p/POLINI-VARIATOR-SPEED-CONTROL--2992.aspx

But yeah I think that maybe the problem my engine running to lean. I will turn the idle mixture screw tomorrow and try to make the mixture more rich because apparently the mixture is too lean and letting in too much air and so that's why it backfires.

The idle mixture screw does just that... Idle mixture. It doesn't change the mixture under normal running. The only way to change the mixture and colour of your plug is a jet swop combined with maybe a freeflow filter.