NC23 Project won't start!

[petrolhead19]

you havent got the throttle cables connected?
pretty sure you need them on or it will rev high lol

As far as i can remember mixture screws are either 2 1/4 or 2 1/2 thats on standard carbs

[gullarm]

Can't see how having the cables connected or not will make it rev high.

The cable stopper is on the carbs, there is an adjuster screw on the carbs itself, if its on the stopper the butterfly valves have been pulled back by the spring.

I would check the carbs are in balance, one or two may be set way too high out of balance so causing the thing to over rev. Hard to spot by eye.

Did you put the jets back in right, didn't alter the heights etc.

Are there any air leaks around the carb rubbers, easy to bend over when putting it all back together.

I would start the bike then unplug one of the coils - see what happens - then try with the other one. If the revs drop but the bike keeps running at least you have narrowed it down to a pair of cyclinders. Then try pulling the HT lead off one of the 2 cylinders that you think may be the problem. Try and narrow it down.

The bike should start and run on two cylinders - mine has several times.

Removing the carbs is a right royal pain.

[RyanNC23]

That's what I thought, no cables means its on no throttle at all.

all butterfly valves seem to be 99% shut? I'm pretty sure the rubbers are all sat nice and firm, on the carbs but will check, I did replace them as the old ones where brittle and cracking (probably due to age)

Can you even alter the height of the jets? the just screw in then you stop? Sorry if I'm being stupid here.

Good thinking with the 'narrow it down' technique, will try this tonight....It's great to hear it running after all this time though!

[gullarm]

Refering to the needles - some people alter the heights or fit different needles amongst other things so setting the whole thing hay wire.

Them carb rubbers are a bar stool - I thought mine were on nice and tight, bike was running fine after puting the carbs back on. Sprayed some WD 40 behind the carbs and the revs shot up on cylinder 1 and also on cylinder 4.

Left the bike running for 20 mins to get them nice and warm then whipped the carbs off and slapped grease over them and put the cabs back on and this time they hit some resistance then made a POP sound and dropped 5mm as they went on. Repeated with the WD 40 spray - no change in revs.

I would be happy its running at least, then tackle the problem one thing at a time.

[RyanNC23]

the needles are priginal plus it ran fine before...

i changed back to the old rubbers cos they are a tighter fit but still over revving!

the rubbers are definately 'poped' on.

tried narrowing it down to one carb, revved to high even when one out of all four was connect (removed spark plug!

this has got me stumped...again!

[gullarm]

How many cylinders was it running on?

I wouldn't remove the plugs, just the HT lead from one cylinder or remove the low voltage wires from one of the coils to kill two of the cylinders. Its a bit hard to remove the HT leads when its running, you may get a shock!

Would removing the plug make it run faster? as there is no compressive resistance in that cylinder - its not compressing anything so the other cylinders have less work to do. Never tried so dont know, my running issues were down to a faulty HT lead and faulty HT cap on different cylinders. And also tickover set too low.

Are the needle sliders down, after I rebuilt my carbs one of mine was sticking down.

You just gotta keep, plugging away.

[RyanNC23]

sorry, I meant I removed the leads...and yes I did get a shock! lol

So I removed one lead at a time, which caused no change and needle sliders? I'm guessing here, but are these the cylindrical sections you can see through the top of the carbs which work as part of the diagphram? if so then yes these are all down, Iv'e got a feeling it's getting to much fuel....so possible a float valve not working correctly?

sounds like carbs off AGAIN tonight :/

[RyanNC23]

quick update... Last night, whilst the bike was revving by itself somewhere near 8000rpm, I took a small screwdriver and pushed on all of the carb butterfly valves, when pushing in 3 & 4 I noticed the revs would drop and idle normally, so took the carbs our, balanced by eye then put them back on, started it up and tweaked a little more whilst they were on, now runs perfect, and sounds mean with no end can!

now on to my next issue...I had the swingarm powder coated, so all bearings were removed, after sourcing these from sweeden! I tried putting them in last night, using a vice, which worked fine until the swingarm edge and bearing were level, now the bearing needs pushing i another 10mm ish, any ideas/tricks for getting bearings in easy?

I tried putting a socked in there and winding up the vice, with no luck!

[gullarm]

Use the old bearings as a wedge! Worked for me on my stem!

You can sand the outer edge a bit so they dont get wedged in

[RyanNC23]

these are crazy tight, as were the old ones!

i dont have the old ones anymore as they broke getting them out! :/