Even with mixture screws right in, still far too rich. I'll be ordering new jets then

I'm as bad as you Eric with my drills!

Edited 28 August, 201214 yr by prankstar2003

How do you know its far too rich? And its not running at all then?

Mega rough! With loads of smoke out the back. Very strong smell of unburnt fuel also

Cool, at least your getting somewhere. This is why you shouldn't drill jets by hand.

I know. I wasn't meaning to drill them, merely clear them. But the crap was so crusted in there, I couldn't push or blow it out. I'm suprised at how such a small removal of material from the jet causes such a dramatic alteration to how it runs. So I've learnt that at least

So your 100% positive ALL the jets are now un-blocked, and there is not un-metered air entering the engine?

Because you said that a few days back

You know you can solder them up and re-drill them? But i'd be doing it in a lathe.

Bench drill be ok for drilling ?

I've had superb efficiency and smoothness with drilled jets.

Tips:

1) Use a new bit, and clean it of brass dust between jets.

2) Hold the jet in pliers with the other hand, use a small battery drill.

3) Drill slowly and only for as long as you have to, then withdraw the jet by hand with minimum twist. The drill bit will still be quite tight in the jet, and once cleaned, it'll be evenly resistant when pulled by hand through all jets (only do this along the cutting edge - never the solid chuck end of the bit).

If you damage a jet, there's no worthy repair imo. I've heard talk of chemical metal or solder and then re-drill.. but - just, no. They're cheaply available new, i think i payed two quid each from some dude off ebay. So if you've gone too big, just get new ones.

I never menat to drill the pilot jets out any bigger, I was only trying to clear the crap out. I didn't think the tiny bit of brass dust that was removed would have such a huge effect. It was literally dust, and very hard to tell from the white, sandy stuff I was drilling out. They were also only drilled out with me literally holding the drill bit with pliers and turnig the jet by hand. I didn't go in with my power drill!

I practically did what mikey has described above with my mains. I knew he had had success DIY drilling so i gave it a shot. It certainly improved fuelling.

However I'm now left with pilot jets that are too rich so i need to buy some new ones

Main jets that I'm not 100% certain what size they are so I'll buy some more (since they are cheap)

As for unmetered air, I can't be 100% sure as I've not had it running with the pilot jets cleaned. I'm pretty sure I have sorted out any sealing problems if i did have any before. I'm still not sure about the spitting back from carb 2, and the lack of response when I cover the breathers. Is there anyway to clean these out as I'm not sure they are removable? Where do they lead too?

That's worrying, if you've pushed a drill bit through thats a smaller diamteter than the jet orofice, i doubt you'd be able to open it out.

Which bit are yo talking about, the idle/slow jet? I know they're fucked! have you not been following?

Only just read about your problems, glad to see that you are making progress though.

I do like the idea of milling groves for 'O' rings, the thing that you need to be careful about if you go for this is that you get the right depth of groove/thickness of 'O' ring - if the groove is too deep or the 'O' ring too thin, you risk not getting a good seal, however if the groove is not deep enough/ 'O' ring too thick, you risk distorting the carburettor flange as you tighten it up.

The ideal way of checking for a flat surface is with a surface plate (if you don't have access to one, a piece of PLATE glass - the stuff that shop windows and good quality mirrors are made of, makes an excellent substitute.) You then need to apply a VERY THIN layer of Mechanic's Blue (Engineers Blue) to the surface plate, slide the manifold face over it with even pressure applied and look at the blue that is transferred to the manifold. Where there is small areas of blue on the manifold face, these are high spots and need to be carefully scraped or filed away. When the manifold comes off of the surface plate with an even blue covering, you can consider it to be flat.

You can 'cheat' by putting too much blue on the surface plate, but this will give very poor results.

You can get Mechanic's/Engineers blue from your local engineers merchant. NOTE This is the greasy blue stuff in a tube or a tin, NOT the spirit based marking out fluid (also blue) which is sold in a bottle.

If I ever open up jet sizes, I use a clockmaker's 'broach', a reamer like tool , which are sold in sets by people like H.S. Walsh and Sons. www.cylex-uk.co.uk or Meadows and Passmore. www.m.p.co.uk

Regards.

Mr Caretakerplus we still are interested to find out the name of the most helpful chap on the forum... spill!!

Good advice there though, always good to make sure its sealing properly.

Maybe your jets were just too rich in the first place, but too lean when blocked!

Your float bowl breathers clear?

Which bit are yo talking about, the idle/slow jet? I know they're fucked! have you not been following?

Never mind

I'm not to sure Nick, How can I check? I've run wire and pipe cleaners through every hole i can find. It goes through some of them but not others, but I'm not sure which ones should be able to pass through and which won't due to bends in the circuit and stuff

Can you not go and have a look nick?

Yeah Nick, come and sort my problems for me There'd be no point atm anyway as I need to order some new jets before I can go any further

Yeah Eric's got all my jets for that kinda engine haha

lool woops!

he needs pilot jets aswell though

Sorry to hi jack . but what pilots should i use in the afh ? lol

Leave them for now.

Will do:). Having a go at setting it up best as i can and may take it to a bike tuner my brother knows .. If not i'll find a sutibal RR.

I'm not sure anyone has ever played about with pilots have they? They only fuel for idle and partially open throttle. If you've got an AFH your probably wide open most of the time, or at leat you should be!

Lol erm ..

Doing the conversion for Looks . Honest ..