Float bowl & Carb top screws

[ThePowster]

Evening fellas.

So I've decided to overhaul a spare set of Nighthawk carbs completely and I've decided I want to paint them too, all black gloss with silver gloss rails and bits and logo on the side.

My first job will be to prepare the carb tops and float bowls for paint, but while I'm doing that I want to replace the carb top and float bowl screws with hex head bolts but I'm not too sure about this yet.

I think somewhere I have a gauge tool to tell me the pitch of the threads, and I'm thinking once I know that I can just measure the length and then the width which I think is the M measurement, i.e. if it's 1mm between the threads and the threads are 10mm long and the width of the threads are 5mm then I'm guessing the correct bolt I would be looking for would therefore be M5 x 10mm 1.0 pitch.

Does that sound about right ?

Also at this stage I'm not sure of the float bowl screws are the same as the carb tops but I can confirm that when I get my hands on them. Currently in bed thinking about the Nighthawk when I should be thinking about women   but Nighthawk's are cheaper.

I think the carbs would look great with a lick of paint and wouldn't tarnish or hold dirt as easy, should wash clean off a gloss finish.

I've got a carb rebuild kit coming with floats and rubber seals, o rings and a dynojet stage 2 carb kit too. This was cheaper than factory pro and it has a larger main jet than factory pro too so I'll be able to go straight piped again and have that lovely sound as well as power.

If anyone knows anything about bolts and screws for the carbs please feel free to add it in this post. Failing that I'll give my maths a bash and see if I can fathom it and add some nice polished stainless hex head bolts that will never rust and never round off ever again.

Of I've got a carbtune too so I can balance the carbs and I fit 4 permanent brass vacuum ports to it for a way future balancing.

I'll of course detail all my findings on this journey and ask for help along the way as I'm not 100% sure on how to fully strip these carbs down but by the time we're done here we'll all be carb fettling gurus.

[Bob H]

I think the carbs would look great with a lick of paint and wouldn't tarnish or hold dirt as easy, should wash clean off a gloss finish.

Kind of reminds me of when you see a truck with a chrome differential cover - the carbs are not really a big visual part of the bike. If I wanted more bling there I would just polish the aluminum.

... so I'll be able to go straight piped again and have that lovely sound as well as power.

It would be music to my ears, but not most of humanity.

[ThePowster]

I'm not painting them so much for visual, it's more to prevent dirt ingress and tarnishing. With a nice gloss finish they'll jet wash clean in an instant.

All the screws are rusty and the carb body is covered in what looks like white salt, so this should preserve them, and when I mate then to this with a stage 2 jet kit I'm hoping it's fit and forget with many years trouble free fettling.



The sound the Nighthawk makes straight piped is so good it makes my ZX-14 sound weak, plus it's still not as loud as.a.Harley and those guys are everywhere. 

[mollusc]

The bowl screws and the cap machine screws are the same pitch.  Slightly different lengths, but you can interchange them.  I swapped mine for black Allen screws.
There's a chain here called Fastenal that had plenty in stock, but any decent hardware store should have metric thread gauges.  Or just try spinning on a series of metric nuts until you find the pitch, then match for length.

[ThePowster]

Thanks Mollusc, never occurred to me to try the spinning on of the nuts, that's a great tip thanks.

[Pete in PA]

Most hardware stores have a test board with all the sizes to test. Just bring 1 of each.

I'd go with stainless.

[mollusc]

Conventional wisdom holds that the reason most carbs aren't painted is that prepping the surface is a real PITA.  Plus if you get a leak anywhere, it tends to wreak havoc with the finish.

[ThePowster]

Here in the UK I've never seen a test board in a hardware store but that's a great idea.

Definitely stainless hex head bolt upgrades.

I'd never considered potential fuel spill affecting the painted finish, but yes now you mention it that's a very valid consideration.

The paint I'm choosing to use will be a gloss engine enamel paint, just a light coat of black and a light coat of silver on the rail and other smaller parts. I think the chrome.hex head bolts against the black body will look nice.