Changing from standard to racing exhaust

[Lasse]

When changing the exhaust, I reckon I should re-jet the bike, what have you others done? :)

when i got my first nc30 it had a standard system cut with a jap home market can,standard jetting,it ran great,got it up jetted to 120/122 and it pulled better from light etc but when i finally got it dynoed the operater said it was very very rich,and put it back to standard....again it ran brilliant if a little weak pulling away from lights...

Any systems that are preferred value/output wise.:)

just whatever you can get,i have seen and heard of jap aftermarket systems like ethos,tsr,beet,yamamoto going for in and around 150 but i have also seen the flip side and seen systems go for £500+,i still think so lovely sounds and performance can be got from just a standard system cut with a can,but the jap ones are usually lighter and give better powers,but weigh up are you going to notice 2bhp and be happy spending an extra £150 to get it ?

Or maybe someone who has a complete front half of the std. system? :)

good call,take off the standard uncut system and buy one thats already cut and bop a can on there,happy days....the cut system you buy you could always replace the rusty old coolars for some s/s ones so they never rot away again

Reason for changing from standard is really that I have a hole in the joint between the front and the rear part.

[royster81]

they have a tendency to leak the petrol into the motor even when the tap has been switched to "off",float valves don't stop it and you end up running a round with a sump full of 2 stroke mix......quickesy way to knacker a motor,ask rick oliver,he sent me a piston once,claimed that was the result of a "pointless" HRC tap mod

are you running jets in or around 150?

[royster81]

pop the old one off then and get new collars welded on,seen a race got hi's done and thought it look like an A1 job

[Lasse]

pop the old one off then and get new collars welded on,seen a race got hi's done and thought it look like an A1 job

Thought about, just didn't want to have a bikeless summer turn-a-round times and all.

[1990nc30]

they have a tendency to leak the petrol into the motor even when the tap has been switched to "off",float valves don't stop it and you end up running a round with a sump full of 2 stroke mix......quickesy way to knacker a motor,ask rick oliver,he sent me a piston once,claimed that was the result of a "pointless" HRC tap mod

are you running jets in or around 150?

No idea about the jets mate they are standard i think, i haven't touched them anyway. The reason for me running it with the fuel tap mod is because it doesn't seem to run any other way so it's not pointless for me, i definately wouldn't of had it done otherwise. When i bought it, it wasn't running due to the vacum in the tap. I bought a fuel tap repair kit off Rick not so long ago to try and sort the problem out but it just didn't work. Can you think of why it doesn't run with a vacum?
I would sort it if i had the know how as people have told me before that the mod is bad news.

[royster81]

the racer is calling up to me tonight to borrow parts,i'll ask him where and who he got to do his and roughly what turn around times etc

if the tap is put together properly and the vacuum attached to the right part there is no reason why it shouldn't work,unless the vacuum hose was blocked/split,or attached to the wrong part of the tap,the tap was assembled wrongly and the vacuum not attached to the motor properly

[1990nc30]

It was all done properly but just didn't work, it ran for a couple of seconds then just died.

[royster81]

It was all done properly but just didn't work, it ran for a couple of seconds then just died.

then it wasn't all done properly,or it would have ran or the problem is still there but the tap mod is bypassing it

[1990nc30]

It was all done properly but just didn't work, it ran for a couple of seconds then just died.

then it wasn't all done properly,or it would have ran or the problem is still there but the tap mod is bypassing it

That's what i think, the problem is still there, the mod is just bypassing it. I just need to find out what the problem is.