Bikemonkey's NC30

[VFRkieran]

hmmm that seems strange then, perhaps it isnt an air leak thats causing it after all unfortunalty i am fresh out of ideas other than spraying some wd40 around the underside of the carbs with the bike running to see if the idle changes.

[Cammo]

Have you set the pilot screws?

[bikemonkey]

I've sprayed gt85 around under the carbs and the revs rise when I do.

All pilot screws are set to 1.75 turns out.

[vfrman]

Then you have a leak. Double check the carbs are fully seated on those new rubbers...

[bikemonkey]

Update time.

I wired in a low beam relay a couple of weeks ago after shitting myself on an unlit section of the A1 with the jap spec candle bulbs.

I drew out this diagram to get my head round what wanted to go where.



Stripped the bike down to get good access to everything.



Now this white wire coming out the brown plug is the switchgear to low beam wire, so I cut that and taped up the end coming out the plug.



Fitted in an inline 15A fuse from the positive battery terminal and wired it up the to relay with some heatproof sleeving to protect it.





Wired in the positive from the battery, white wire from the switchgear, positive to the headlights and a ground. Not the best soldering in the world, but I'm getting better.



Put a splitter in the positive and ground wires of the headlights for obvious reasons. Green tape is the ground and red the positive.



Wired in a new H4 plug for each headlight as the old connectors would have fallen to pieces if I disturbed them. Ran the negative from the plugs straight to the earth point near the front coil.



Then to fit the bulbs I cut the two offending tabs off and stuck on my adapter rings.



Taped everything up neatly and went to test it. Nothing. Balls.

I unwrapped all the tape, checked all the connections and couldn't see where I'd gone wrong. Then I was about the have a serious hissy fit when I realised that I hadn't reconnected the brown plug

I haven't got any pictures to compare H4R and H4 but I can say that H4R low beam is like having candles stuck to the front of your bike compared to the H4's. I can actually see unlit roads now



Now onto the carbs. There wasn't an air leak at all, they were just fucked. Play in the throttle linkages made them impossible to balance, and a fucked choke system meant I couldn't get the mixture screws to the proper setting.

So I bought another set and had them ultrasonically cleaned, replaced all the seals with a viton kit from Rick O and replaced all the screws for allen head bolts. Before and after pics of the cleaning, plus swapping jets and screws over, with a old and new comparison.

Before cleaning.







I polished up the slide covers myself.



And after cleaning.









Partially splitting the carbs and replacing the seals.





Now today's work has been outside freezing my arse off for the last 4 hours.

Fitted Rick O's choke conversion as my choke cable was fucked too.



Putting the main jets into the clean carbs and changing the screws/bolts. (Yes I know the top plate is on the wrong way, I realised this later and rectified after a bit of swearing)





Got myself a new airbox, you can see why in this picture. But I didn't fit the new bottom plate as I could not see how the bike would run with the snorkel going into a closed area with no opening to the rubber flap below.



Then I got the shiny carbs onto the bike after fitting up the carbtune gear.



And balanced nicely. This photo was just before I made a couple of final adjustments to the linkages, the final balance was near spot on.



Idles lovely now. Not like the old set idle-ing where they wanted, usually between 2.5k and 1.5k, without me even touching the idle adjuster or choke or anything. They did as they liked, fucking things, only good for spares now.

Haven't been out and rode the bike yet to test.

Carb settings are now:

Pilots: 35
Mains: 120F 122R
Needles and emulsion tubes in correct places
Float heights set
Mixture screws 2.25 turns out
No washers under the needles
Slides drilled to 2.5mm (as they came with the new carbs)

Will probably have to adjust the needles, but we'll see first.

On a side note my battery has been doing weird things ever since it died whilst riding the bike due to the positive reg/rec connector coming loose. It cranks the engine like it's nearly dead, then if you leave it a minute it cranks harder, then leave another minute and finally cranks hard enough to start the bike. This is with the bike just being started when cold or hot, left for hours or minutes.

It's a lithium ion one, and I'm too skint to buy another now so I've got a motobatt one on the way. The motobatt has 4 terminals which are apparently safe to use all 4, which will massively help as I now have so many ring terminals on the battery it's getting hard to find the little nut with the bolt!

Oh and to finish, a little whoring picture of how she stands now (scruffy bike).

[VFRkieran]

Carbs are looking very good mate, only thing id suggest is to use the airbox base plate because you may have running issues without, if i remember correctly there is a small gap right in the vee of the frame and between the airbox base plate this along with the rubber flap underneath smooths out the airflow making the bike run well. Without it the air is too turbulent and you might find a few issues up high in the rev range.

[bikemonkey]

Hmm, I just don't see how that works. It's like the snorkel just opens into a closed space.

I'll try it with the old base plate that's had the front cut off and see.

Will probably be fiddling with the needle washers soon anyway, so I'll change it then.

[CMSMJ1]

The bike sucks the air in. You don;t need any free air or any airflow at all really - it is a 400cc air pump and will suck like a cheap ho whatever you do to the airbox. Fit the plate dude!! try it back to back but try it..

[bikemonkey]

Now that you stick it in those terms

I'll have to hope for some half decent weather to do some proper testing.

[CMSMJ1]

Some weather to ride would be nice..

To be sure though mate - you have done a great job on that bike. It is bob on.