Metalwork...Honda cycle jet sizes?

I got the new used coil in the Honda XL350, after machining a new mounting system, new condenser and cleaning up the wiring and now it
spluges out a really nice bright blue spark. So I cleaned out the gas tank, put in a pint, double inline filters, pulled the bowl and spritzed the carby with carb cleaner and tried to start it. It would run for a few seconds, or at least bark and once I got it running for a few minutes. This is when I discovered the clutch wasnt releasing...when I kicked it into gear.
Getting the bike down off the table saw and pulling the table saw out of the sheetrock ........
Anyways...I figured the carby needed to be cleaned out, so I took it apart and cleaned all the various ports and passages, replaced the various o rings...(Ive never seen a carby with that many seals, o rings etc etc...daaayyyam...thankfuly Ive got a good supply of O rings..thousands actually..I bought a pallet load)
I discovered that the "slow jet" was someones kludge..a 8-32 x1 bolt some yoyo had drilled a .140 hole down the center (well..mostly down the center...) and stuffed it up into the casting. I think it may have been glued in place, but removing it took some effort and it wont stay in place. Based on parts breakdown diagram...its supposed to be a totally different shape, screwed into the casting...where there isnt any threads..must have been stripped out. I can machine a new one..not an issue, tap the carb casting, turn and thread a new jet from brass, no biggy. But I dont know what the jet ID diameter is supposed to be. The various parts lists say its supposed to be a #48 jet. No idea as to the ID.
It of course is metric. While my HLV-h will thread metric..I cant tell what the thread inside the jet well really is. I dont have any metric thread gauges.
When I crank the bike over with the plug removed..it pushes out a very visible cloud of fuel, and it wont start...wets the plug. So obviously the homemade jet is way way over size and is probably leaking . There isnt a Honda shop within 45 miles and the one I called couldnt tell me what the ID was supposed to be. Float has been set to proper height as has the needle and jet.
Ive got drills down to .003, so punching a new jet out isnt an issue
Anyone have any idea of how these are supposed to be sized? Is a #48 ..48 mm? That would make it about .019" which sounds a bit small for an idle or start jet, but might be ok....shrug. Im not a motorhead. Ive got some .018 drills ( #77 drill) sp could knock one out easily....
I figure that the only reason it started at all was the jet was partially plugged up....shrug.
Too small and it will idle lean and get hot and burn something up, too big and it will continue to flood out.
Any ideas? Work has been rather slow, and over the holidays Ive got time to work on the scooters along with other more important projects so would like to get the Honda running. I take turns working on the 3 bikes, and its the Hondas turn.
http://mysite.verizon.net/dorkpunch/id68.htm
Thanks
Gunner
"They couldn't hit an elephant at this dist..." Maj. Gen. John Sedgewick, killed by a sniper in 1864 at the battle of Spotsylvania
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On Sun, 21 Dec 2008 04:17:05 -0800, Gunner Asch wrote:

A quick google suggests that Keihn sizes are metric (48 = 0.48mm), but Mikuni are not (flow-related?)
Memory suggests that just drilling a hole may not get the same result as a factory jet; small long holes and surface finish issues.
It might be cheaper & quicker to buy a used carb from ebay.
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Gunner Asch wrote:

Having a tiny bit of experience with bikes and carbs ... You're on track , the jet size is a .48 MM . I know that sounds small , but a lot of HD big twins run an idle jet that size . It's actually low speed , idle mix is controlled by a needle . What does the carb look like ? Does it have a vacuum controlled slide and a butterfly or a butterfly only ? Choke plate or enricher port ? Does it mount eith a flange or a rubber sleeve into a spigot ?

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On Sun, 21 Dec 2008 07:20:01 -0600, "Terry Coombs"

http://www.cmsnl.com/honda-xl350-k0-us_model844/partslist/E++07.html
Mounts to a rubber boot 15 degrees or so offset to the head. Called a side port engine. Rubber boot is stiff, but still good, no leaks.
That big visible cloud of gas that comes out the plug hole tells me its slurping up a shitload of fuel from somewheres, and the only thing not nominal (as far as I can tell, is the bastard idle jet)
"They couldn't hit an elephant at this dist..." Maj. Gen. John Sedgewick, killed by a sniper in 1864 at the battle of Spotsylvania
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Where to get jets (don't even try to make them, have to be reamed to tenths) http://www.motorcyclecarbs.com/Keihin_Jetting_Components_C69.cfm
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