Carb parts ?

[Zaz]

Apologies for a double post, i am copy/pasting this from the carb jetting sticky as im not sure how often that gets looked at now, its 15 pages long !

Great guide, i will be following it when i set about rebuilding my carbs, however, a couple of questions first:

I have a 1989 'k' import nc30 with a Viper endcan, the bike has done 4500 miles in 10 years, had a restrictor kit fitted for the last year (400 odd miles use previous owner - now removed) and is suffering a bit with stalling, high idling, power delay etc. Runs smooth when on a run, though it did die on me last week.

Anyhoo, i have all new OE clutch parts on the way, clutch and choke cables too, so i thought while im at it i will do the carbs too.

So, i am compiling a list of parts i will then buy, so far i have:

main jets 118f/120r
float chamber gaskets
probably emulsion tubes
probably needles
0.5m washers
probably OE throttle cables

Questions are, what other bit are recommended while i have it opened up, what o-rings will i need and for where, price wise what is my best option for sourcing parts and to save trawling all 15 pages (evil eye off mrs for being online again) what part numbers am i looking at ?

Thanks for your time :)

[Neosophist]

Erm, why throttle cables, needles and emulsion tubes?

These are often never changed.

Dont mix up the parts between the carbs either the rear emulsion tubes might be different from the front

[uber pikey]

You only need the jets, washers and gaskets the rest will be over kill, follow the thread and check everything it tells you to and don't be lazy.

[Cammo]

You only need the jets, washers and gaskets the rest will be over kill

+1

The part numbers for the main jets are in the guide. Rick Oliver (forum member) is the best source for float chamber gaskets, he sells o-rings that fit nicely and are a fraction of the cost of genuine gaskets.

Most carb parts tend to clean up fine with a soaking and a bit of elbow grease. If anything I find it's the pilot jets that are sometimes gunked up so bad that it's safer to buy new ones (they have the smallest orifice of all of the jets), but best to see what the internal condition of the carbs is like before buying any.

[Zaz]

Following suggestions here and as i had an outstanding delivery from GF, i placed my order with him, worked out the same as RO prices for the same kit.

Just ordered jets shims and gaskets for now, rest i will get as i need it.

Cheers chaps :)

[Zaz]

I have started stripping the carbs down but have hit a snag. The guide suggests the front emulsion tube is 4 holes with the rear being 5 holes. Thats fine, but which is th front and rear ?

If you sat on the bike and looked down, am i right in saying the carbs closest to the front of the bike are the front carbs, the ones closest to your nutsack being the rear carbs ?

If so, then whoever did my carbs last got the emulsion tubes the wrong way round, i want to make sure im sticking them back in properly before putting the bike back together :)

[porndoguk]

I have started stripping the carbs down but have hit a snag. The guide suggests the front emulsion tube is 4 holes with the rear being 5 holes. Thats fine, but which is th front and rear ?

If you sat on the bike and looked down, am i right in saying the carbs closest to the front of the bike are the front carbs, the ones closest to your nutsack being the rear carbs ?

Correct

If so, then whoever did my carbs last got the emulsion tubes the wrong way round, i want to make sure im sticking them back in properly before putting the bike back together :)

its a common school boy error

the engine Cylinder number are quite simple to remember

think of an N pattern starting at the rear/back left is C1, front left is C2, rear/back right is C3, front right is C4. so think of the N for NC30 as the cylinder numbers.

[uber pikey]

You are right mate, as you are sat on the bike the carbs at the front are the front carbs, it gets a little confusing once they are out and upside down but front and rear is reference the position they would be sat on the bike.

[Zaz]

All done, well, i say all done, i couldnt put the extra shims on the needles as the cover screws have been rounded off by a previous owner, something to do another time.

Also, managed to snap a bolt on the crancase cover, its at the top right, ive run the engine for 20 mins and took it out for 5 miles to see if there are any leaks but there arent that i can see so far.

Runs a lot better now, much more 'go' in it through the range, little bit of a flatspot midrange but hopefully that'll be sorted when i get round to adding the shims.