Help/Advise needed.

[ChowderV4]

Ok basically i have a nc30 which is currently running a ethos half system and a bluflame end can.
i followed the carb guide and jetted it 118 front 120 back, drilled slides raised needles and pilot screws set to 2 and 1/4 turns out and have tryed standard and dual density filters.
the problem being i still have a nasty flat spot between 4.5 and 7 thousand revs, im asking anyone if they have any recommendations or advise on curing this.
because if i cant get it fixed in the next month im going to revert back to a standard system and standard jetting etc.

my plan is to buy another set of carbs, ( im interested if anyone is selling). the plan being set up the carbs that are off the bike, then swap them over. see how it runs and adjust the other set thats off to try and cure it.
im also wondering if rvf carbs are going to have any advantages or not.

if anyone is running a similar set up, ie. half system standard engine & cdi, i would be grateful if you could share your settings so i could try them.

any help or advise will be mucho appreciated as i really want it running sweet.
im also interested in buying any sets of carbs , different jets etc.

cheers,
Ben

[alexwitham]

PM sent re carbs.

[CMSMJ1]

So...this flat spot. Describe it...

[Cammo]

... and have tryed standard and dual density filters.

the problem being i still have a nasty flat spot between 4.5 and 7 thousand revs, im asking anyone if they have any recommendations or advise on curing this.

What sort of difference did the 2 filters have on the flat spot? You are riding the bike to test it yes (not just revving in neutral)?

[ChowderV4]

... and have tryed standard and dual density filters.

the problem being i still have a nasty flat spot between 4.5 and 7 thousand revs, im asking anyone if they have any recommendations or advise on curing this.

What sort of difference did the 2 filters have on the flat spot? You are riding the bike to test it yes (not just revving in neutral)?

basically it revs nice up till 4.5k then hesitates and is a bit fluffy then revs nicely from 7k onwards.

And to be honest cammo I couldn't really tell the difference. ( and yes I am riding it)

[Cammo]

You could try lowering the needles back to standard height (1 washer) and using the standard filter.

See how that goes. The results of doing this may not fix it but it will tell you further what the issue may be.

[ChowderV4]

Alright I'll give that a bash and report back. Should get time to do it Friday/Saturday

[ChowderV4]

Update:

I tryed a standard air box I had lying around which had the snorkle removed and had a dual density air filter in, that ran terribly.
I have since put standard filter in and airbox with snorkle which runs better, but the flat spot is still there.

[Neosophist]

Bit fluffy low down..

How is the idle?

Is it a bogging down (rich) or a tight (lean) feeling?

[ChowderV4]

Before I had my carb. Off last it idled perfect but had the flat spot between 4.5 and 7k
.
I think I
may have torn one of the diaphrams last time I had them off because the idle is all over now.