nc30 carb slides have extra hole rather than an enlarged one

[b1hrider]

Hi,
Currently in the throes of trying to sort my carburation. My slides all have an extra 2mm hole drilled opposite the existing one, rather than the usual single hole opened up to 2.5mm.
Anyone have theories on why this may be, and what effect it would have?
Thanks guys.

[Neosophist]

are the bottoms flat or curved?

the nc24 slides have two smaller holes, if they are stock slides i guess its the same as enlsrging the stock hole

[b1hrider]

Flat bottomed ones, std nc30 as far as i know. Guess area wise, 2x 2mm holes similar to 1x 2.5mm. Just know these carbs have been fingered with in the past, (adjustable needles were fitted) so wondering what else could be causing my probs.

[Neosophist]

Your problem is what?

[b1hrider]

With the original needles in, it was missing like mad from about 8 to 12k, so changed to rick oliver needles, but it's currently suffering from missing like mad on partial throttle openings regardless of rpms. Between about 1/4 to 1/2 throttle it's terrible. However, not yet checked float height, or touched idle screws as it throttled up fine before, though i realise that these may need looking at. Bike has horrible stubby oval viper race can with a db killer baffle in it. Took the baffle out, slightly better, but no where near right yet. Carb has been cleaned out as far as all main and idle jets, has 118f / 120r jets. Guessing it's overfuelling badly there, tailpipe is really badly carboned up.
Cheers for any help offered!

[Morespeedvicar]

Put some hot melt glue or body filler in the other hole see wat happens, is the air filter clean? I wouldnt think its anything to do with the pipe. Deffo check the float heights and set the idle screws, cant remember how many turns out there supposed to be sorry, think its about 1.5 turns.
Cheers
Ian

[b1hrider]

Yeah, airfilter good and running totally standard inlet setup. Idle screws should be 2 1/4 turns going by cammo's guide and rick olly. So that's this saturdays job, and see if it makes a difference. Will do those first, then at least if i decide to try block one of the slide holes i don't need to take carbs off again.
Have got an offer of another set which might be worth getting if it's got standard needles in etc, for spares as much as owt.

[b1hrider]

So checked idle screws etc, still suffering same probs, will post new thread regarding partial throttle opening problem.

[CRM]

have you checked the valve clearances ? they will make quite a difference.

[b1hrider]

Hi,
That's something that never crossed my mind, no doubt due to my lack of understanding on the matter. The bikes got 46k's on it, and prob been neglected so guess they're well overdue. Was definitely on my list of to do jobs for winter anyway, wanted to concentrate on getting it running right before I delved too deep, and didnt realise that they'd affect it. Is it because if one cylinder has tight clearances it'll be down on fuel?