Dellorto SHA 14/xx, 15/xx

December 24, 2014

 

Dellorto SHA is a family of Italian moped or mini-bike carburetors. SHA’s have flat throttle slides and no jet needles. They all have the same outer size and main body appearance, with a 59mm round flange for an air filter. They have been produced for in Italy from the 1960’s to the 2000’s. In particular the Dellorto SHA 14/12 and 14/9 carburetors were on tens of thousands of US mopeds from 1976 to 1985.

Carburetor Size: The venturi is where the air mixes with gasoline. It is also where the air passage gets narrower, to cause a higher air speed in order to atomize or break up the liquid fuel into smaller droplets. With Dellorto SHA carburetors, two numbers are used to describe the size of the venturi. The first number is the venturi exit, and the second number is the venturi entrance. So looking at an SHA 14/12 from the front you see a 12mm hole, and from the back (engine side) you see a 14mm hole.

Choke Type: The choke is a lever you push or pull, “on” for cold starting, or “off” for normal running. There are three types used on Dellorto SHA carburetors:

A  direct lever  push down lever on carb to put choke “on”, give full throttle to release it “off”
B  linkage lever  same operation as direct lever
C  cable choke  cable goes to a handlebar thumb lever, pull to put choke “on”, let go for “off”  

 

Cable choke is needed when the carburetor choke lever cannot be reached by hand.

Arbeo-Dellorto SHA carbs were made in Spain under license for the Spanish moped Derbi. They were more goldish colored, and tended to leak fuel past the float seat.

Generic SHA: Since the 2000’s there are China made remakes. Most have different screw threads, not Italian-metric. Many have M5-0.80 jet threads, different from Dellorto M5-0.75. The Runtong remake carb has M5-0.75 jet threads. So it can take any Dellorto M5 jet, but many other generics cannot.

 

Original Carburetors

’60-85 Dellorto SHA 14/9 has a lever choke,
20 mm clamp, 16 or 18 sleeve, jet 44, 46 or 48.
Original on 20-25 mph models.

’60-85 Dellorto SHA 14/12 has a lever choke,
20 mm clamp, 16 or 18 sleeve, jet 48, 50 or 52.
Original on 25-30 mph models.

’85-06 Dellorto SHA 14/12P has a linkage choke,
21 mm clamp, 18 sleeve, jet 51 or 53.
Original on 25-30 mph ’85-06 Tomos.

’75-86 Arbeo SHA 12/12 has a lever choke,
20 mm clamp, 18 sleeve, jet 52. Spain 14/12
Original on ’75-86 Derbi models.

’86-90 Arbeo SHA 12/12C has a cable choke,
20 mm clamp, 18 sleeve, jet 54. Spain 14/12C
Original on ’86-90 Derbi models.

 

Replacement Carburetors for Sale


Dellorto SHA 14/12L has a lever choke,
21 mm clamp, 18 sleeve, jet 57, air cover #39
Genuine replacement for SHA 14/12.
Can replace carbs that clamp to 16-19 mm intakes.
$73.0 with 16, 17, or 19 sleeve,  $70.0 with 18 sleeve


Dellorto SHA 14/14R
has a cable choke,
19 mm clamp, no sleeve, jet 54, air cover #38d
Replaces Gurtner Motobecane AR2 side-mount.

$85 with choke and throttle cable inner wires


Dellorto SHA 15/15C
has a cable choke,
21 mm clamp, 18 sleeve, jet 70, air cover #39

Can replace carbs that clamp to 16-19 mm intakes.
$73 with 16, 17, or 19 sleeve,  $70 with 18 sleeve

 

Clamp size: These new replacement carburetors only clamp tight when the intake pipe is exactly the right size. Many intakes are made slightly smaller or become smaller from wear. When the clamp screw is tightened fully, the carburetor can still move, and eventually slip off. For a 18 sleeve, a 18.00 to 18.10 pipe would clamp tight, but 17.95 or less pipe would not clamp tight. That is not very much forgiveness.

Cut up a can: A strip cut out from an aluminum can, with scissors, can be placed under the sleeve. Thickness is 0.1mm. Either a 1/3 circle or a full circle can be used, as needed. A full circle adds 0.2 to the clamp diameter, for a 17.80 to become 18.00. A 1/3 circle adds 0.1 mm, for a 17.90 to become 18.00. A thin aluminum baking pan is thinner than a can. A thinner full circle is better for when only a little is needed.

Most brand new original Garelli, Minarelli, and Tomos intake manifolds (pipes) are 18.00. But some are 17.95, and actually need a 1/3 strip of aluminum can inserted in order to clamp tight and proper, with new original carburetors.

Cable pipes are for redirecting the throttle cable. Pipe thread is M6-0.75. Adjuster thread is M5-0.75. A throttle cable end can pass through, except 2d. Bikes with front carburetors don’t need them, because the cable goes straight up. Others have gas tanks or floor boards that the cable must go under or around.

a
Although some are shown with adjusters, cable pipes do not include #3a pipe adjuster and #3 pipe lock nut.

 


                 P A R T S    L I S T

price colors mean used  new  new
part# colors mean Dellorto, Minarelli, Tomos, other

pic#  price  part#    description
1    $2.00 1476   rubber boot long
1
a  $2.00 1476A 219624 rubber boot short

2    $5.00 1104   top adjuster with nut A13 M6-0.75
2a  $13.0 7423   cable pipe Vespa   22×30 90º use 2ar
2ar $6.00 7423r  cable pipe Vespa   22×30 90º 
2b  none  3698   cable pipe 6560    20×28 90º use 2br
2br $16.0 3698r  cable pipe xxxx    20×30 90º

2c  $13.0 3600   cable pipe 6680    long 70º use 2cr
2cr $8.00 243152 cab. pipe Tomos  long 70º 

2d  $7.00 pipe2d cable pipe Derbi   long 70º no adj.
2e  $7.00 80210400 c. pipe Garelli  medium 35º 
2f    $15.0 163515835  pipe GarVIP short 45º
2g  $5.00 pipe2g cable pipe xxxxx  30×27 90º
2h  $5.00 219623 cab. pipe T. A35  med. 70º 

2j   $5.00 pipe2j cable pipe xxxx    med. 32º
2k  none  10854 cable pipe  xxxx    long 50º
2n  none  pipe2n cable pipe xxxx    long 40º

2as $9.00 53036 cable pipe set 1+2ar+a
2cs $14.0 53037 cable pipe set 1+2h+2cr+3a
2ks none  53038 cable pipe set 1+2k+3a 
2js  none  53073 cable pipe set 1a+2j+3a  
2
gs$9.00 53040 11630cu   set 1+2g+3a
2fs  none  265146 Malossi   set 1a+2fr     
2ns none  53058 cable pipe set 2n+3b      

3    $3.00 1691   cable pipe nut M6-0.75  special     
3a  $6.00 219625 pipe adjuster with nut M5-0.75

3b  $3.00 1692   pipe adjuster lock nut M5-0.75

pic# part#  price   description
4   3318    $2.00 top screw M4-0.75 x 14 slot not M4-0.7
5   5011    $1.50 narrow washer M4 
  6110M$5.00 6320 top bare metal
6a 6110    $5.00 top bare white plastic
6b 6110    none  top bare black plastic
6c 219596 $16.0 top bare black angled hole 30° 85-06 Tomos
6d top6d  $15.0 top assy metal   6+7+8+9+10
6e top6e  $15.0 top assy white  6a+7+8+9+10
6f  13662  none  top assy black  6b+7+8+9+10
7   6115    $2.00 6510 hinge pin (in top)
8   6259    $2.00 6460 spring choke (in top)
9   6112    $5.00 6450 lever choke trigger


10
   6111 00 $3.00 6410 gasket for carb top
11   3346 00 $10.0 6480 spring throttle return
12   6108/64 $12.0 6590 slide throttle #1 metal 219580 25mph
12a 6108/2x $8.00 slide throttle #2 metal 20mph
12b 6108 00 none  slide throttle #12 plastic


13   4190 0  $5.00 6620 screw M5-0.75 x 15 not regular metric
14   3385 0  $1.50 seal washer 5 x 9 for metal banjo not plastic
15   6106 0  $8.00 6530 banjo metal angled out 3/16″

15a 219584 $9.00 banjo inlet metal straight 3/16″
15b 9249 0  $7.00 6535 banjo plastic angled out 3/16″
15c Der15c  none  banjo inlet thick 1/4″ put a thin hose over 15a
16   6109 0  $5.00 6360 filter fuel plastic mesh
17   6304 0  $2.50 6350 nut M6 teardrop most have regular nut
18   6159 0  $3.00 6420 gasket for air filter
19   6105 0  $3.00 6470 spring for choke plate


20   6112    $7.00 choke plate-lever short  type A lever choke
20a 6114    $7.00 6570 choke plate-lever medium
20b 8026    $7.00 6580 choke plate-lever long   Cimatti type
21   5417    $3.00 6520 pivot step-bolt choke
22   8773    $2.00 hinge pin 6500 Ø2.0 x 16.5 
23a 14148  $7.00 21-16 sleeve, inner lip for 16.00 mm intakes
23b 12914  $7.00 21-17 sleeve, inner lip for 17.00 MB (some)
23c 10811  $7.00 21-18 sleeve, inner lip for 18.00 mm intakes
23d 11362  $7.00 21-18 sleeve, outer lip for 18.00 mm intakes

23e 227324$5.00 rubber ring,  for 23d  21 x 16 x 3.5 angled
23e 227324 $0.00 only for carbs that have sleeve 23d Tomos
23f  10146  $7.00 21-19 sleeve, inner lip for 19.00 Peugeot, MB
23g 2300    $7.00 21-19 sleeve, outer lip for 19.00 Peugeot, MB

23h 6124    $5.00 20-16 sleeve, inner lip for 16.00 Morini MO1,
23h cont     Demm, Benelli G2, Tomos ’74-85, Batavus M48
23i  6448    $7.00 20-18 sleeve, inner lip for 18.00 Minarelli V1,
23i  cont     Garelli, Tomos ’85-06, Morini M1
23j    19-17 $22.0 19-17 sleeve, inner lip for Motobecane (some)
23k 114482 $12.0 18-16 sleeve, inner lip for Vespa type SHA
24   6305    $2.00 clamp bolt M6-1.00
25   6140    $4.00 idle screw M4-0.70 x 25 regular metric !
26   3606    $2.00 spring idle Ø4 Ø6 x 12


27   2838    $10.0 float needle valve L=17.0

28 jet M5-0.75 thread
Left is genuine, right is aftermarket. The sizes do not agree.
See Dellorto Jets. These are all genuine jets with the INC logo.
28 1486/42 $5.00 jet 42 0.0178″=0.451
28 1486/43 none   jet 43 0.0182″=0.462 pre-78 Ciao & Bravo
28 1486/44 $5.00 jet 44 0.0186″=0.472
28 1486/45 none   jet 45 0.0190″=0.483 78-on Ciao & Bravo
28 1486/46 $5.00 jet 46 0.0194″=0.493
28 1486/47 $7.00 jet 47 0.0198″=0.503
28 1486/48 $5.00 jet 48 0.0202″=0.513 most 20mph mopeds
28 1486/49 $7.00 jet 49 0.0207″=0.525 78-on Vespa Grande
28 1486/50 $5.00 jet 50 0.0210″=0.533 76-80 Garelli (some)
28 1486/51 $7.00 jet 51 0.0215″=0.546 85-91 Tomos late A3
28 1486/52 $5.00 jet 52 0.0219″=0.556 most 30mph mopeds
28 1486/53 $7.00 jet 53 0.0223″=0.566 92-95 Tomos early A35
28 1486/54 $5.00 jet 54 0.0227″=0.577 86-90 Derbi (flat reed)
28 1486/55 none   jet 55 0.0231″=0.587
28 1486/56 $5.00 jet 56 0.0235″=0.597 96-06 Tomos late A35
28 1486/58 $5.00 jet 58 0.0242″=0.615
28 1486/60 $5.00 jet 60 0.0247″=0.627 96-06 Tomos+exhaust
29 6122-80 $18.0 float all white plastic
30 6123-00 $2.00 float gasket ring all new ones are round
31 6107-96 $5.00 float bowl metal
31 13412 0 $5.00 float bowl plastic          
32 3598-36 $4.00 float bowl screw M4-0.75 x 18  not regular metric


33 4611-50 $4.00 cover clamp ∅60 replica with screw
34 4617-36 none  clamp screw M4-0.75 re-thread nut to use #8-32
35   6117   $9.00 air filter metal screen
00x 0 ∅58 id air covers  TL# bare says   color  holes

36   7758   $23.0 cover #0 assy 00 000 black 2-∅10 with #40 tubes
36   7204   none  cover #0 bare 00 000 black 2-∅10, no tubes
36   9887   $10.0 cover #1 bare 00 000 black 2-∅12, no tubes
37   8602   none  cover #7 bare S33 00 black 2-∅12, no tubes
37   0000   none  cover #0 bare S33 00 grey  2-∅12, no tubes
37a 8603   $11.0 cover #5 bare S3 F44 black 2-∅12, no tubes
37a 0000   none  cover #0 bare S3 F44 grey  2-∅12, no tubes

37a 10574 none  cover #0  bare 00 000 black 3-∅12, no tubes
37b 8632   none  cover #0  bare 00 000 black 2-∅12, no tubes

38   5660   $32.0 cover #0  bare S1 Min gray  2-
38   5660   $25.0cover-clampS4S1 Min gray  2-
38   5660M $15.0cover-clamp S4 S1 Min black 2-

38a 5346   $12.0 cover #3 bare F27 00 black 2-∅12, no tubes
38b 5199   none  cover #0 bare 10236  black 2-∅12, no tubes
38c 9723   none  cover #6 bare Garelli  black 2-∅10, no tubes
38d 53056 $21.0 cover #4 assy F51 00 black 2-∅12 with #41 tubes
38e 12971 none  cover #2 bare F49  00 black
39   
53051 $17.0 air cap, clip, screen set
39a 6183   $10.0 air cap only ∅58 ID
39b 6235   $6.00 clip only
40   7195   $7.00 air inlet tube small Ø8 Ø10 x 20
41   5309   $8.00 air inlet tube large Ø9 Ø12 x 50

42
4
2    060420 $22.0 air filter, fits 96-06 Tomos, needs a bigger jet
43C  53057   $8.00 cable choke plate set type C  43a+43b+21
43a  plate43  $6.00 cable choke plate only  type C
43b spring43 $3.00 cable choke spring only
44B  223025 $7.00 pivot shaft w/linkage  type B, gets rounded

45B  223027 $2.00 spring for pivot shaft  type B 
46B  223026 none  choke plate xxxxxxx type B
47B  223028 $7.00 choke lever external B, gets hourglass-shaped
48B  031930 $1.00 lock washer M4  B, better to weld 46,47,49
49B  031073 $1.00 nut M4-0.70      B, better to weld 46,47,49

a
50
gset50 $6.00 gasket set SHA14   10, 14, 30
51  52533 $10.0 gasket set pre-’85  10, 14, 30, 18, 18, 1a, 55, 56
51  52533 $10.0 for older SHA14 pre-1985 with 20mm clamp size

52  52579 $12.0 gasket set post-85 10, 14, 30, 18, 23e, 23e, 57
52  52579 $12.0 for newer SHA14 1985-on with 21mm clamp size

55  ring55 $2.00 square rubber ring 14 x 20 x 2.0 for some pre-85
55  ring55 $2.00 only for 20mm intakes (when no sleeve is installed)

56  ring56 $1.00 tiny rubber o-ring  3 x 6.5 x 1.75 only for  ?
57  ring57 $2.00 square rubber ring 15 x 21 x 2.0 for some post-85
57  0-ring57 $2.00 only for 21mm intakes (when no sleeve is installed)


Tomos 85-95 A3+A35
51 219374 $10.0 junction sleeve center mount
52 219373 $19.0 air box bare (silencer)
Tomos 85-91 A3  (pre-85 was Encarwi Ø9 intake)
53 214330 $12.0 intake tube Ø12.5 x 60 straight
60 025195 $0.60 intake screw M6x30 hex
61 026289 $0.50 intake screw M6x18 hex
62 031932 $0.20 washer M6
63 219371 $15.0 center intake A3
63 219564 $18.0 center intake A3 (oil inject)
64 219372 $5.00 intake gasket thin

Tomos 92-95 A35
53 223606 $9.00 inlet tube Ø12.5×110 curved
65 026566 $1.50 intake screw M5x20 allen
66 031931 $0.20 washer 5mm
67 227592 N/A     center intake A35 (oil inject)
Tomos 96-06 A35
55 229705 $14.0 junction sleeve side mount
56 229706 $2.50 inlet grommet
57 229769 $35.0 air box assy 57, 58, 59
58 044438 $1.00 air box screw
59 229704 $7.00 air filter foam
68 223748 $3.00 reed valve gasket
69 222238 $34.0 reed valve 2-petal
70 229707 N/A     side intake (no oil inject.)
71 229716 $21.0 side intake (oil injection)

An oil-injection intake has a M6-threaded hole for the oil line. A no-oil injection intake does not.
Plug the hole with a M6x8 bolt and M6 seal washer, to convert oil-injection to no oil injection. 

 

 

 

 


Jet Drills

January 27, 2007

 

Above, a Tomos A55 idle jet (M4 thread) is physically bigger than a Puch Maxi main jet (M3.5 thread), but the hole size is much smaller. The photo shows how the #25 jet, 0.010" (ten thousandths of an inch), will allow the thinner wire of the wire wheel to pass through the hole, but not the thicker wire of the wire brush. This is a useful cleaning technique.

Above, a Tomos A55 idle jet (M4 thread) is physically bigger than a Puch Maxi main jet (M3.5 thread), but the hole size is much smaller. The photo shows how the #25 jet, 0.011″ (eleven thousandths of an inch), will allow the thinner wire of the wire wheel to pass through the hole, but not the thicker wire of the wire brush. This is a useful cleaning technique.

This will help you visualize how small these drills and jets are!

Moped main jets range from 0.018″ (#77 drill) to 0.026″ (#71 drill). 

Moped idle jets, like Tomos A55, are 0.011″ (smaller than #80).

An average human hair is 0.003″ (three thousandths of an inch).

So moped jet holes are 4 to 9 hairs wide!

Shauns well used jet drill container from the 1980's

Shaun’s well used drill container from 1987

 

Jet Drills: All through the late 1980’s and 1990’s, Shaun (at Royal Cyclery and later at Myrons Mopeds) used the USA-made jet drills to service carburetors. The drill sizes are an American wire gauge. They did not vary in size. Those 20-piece Drill Sets 61 to 80, cost $40 in 2015, $33 in 1998. and $29 in 1987. Some are in clear plastic round dome containers, and some are in conventional metal drill set boxes.

 

 

Drill Set 61-80 USA-made

Drill Set USA-made

Jet Drills made in China

Set 1 China-made

China-made Drills: In the 2000’s there were many China made tools sold in “surplus” tool stores. The China made 20-piece Drill Sets 61 to 80, sell for $7 to $10, or one fourth as much. They have an excellent blue plastic container, that only lets out one at a time. But the drill sizes are all wrong. From about 2010 to 2014, Myrons Mopeds sold these inexpensive drill sets, not knowing that the drill sizes were inexact, to say the least.

So although the China sets cost one forth as much, they only have about seven or eight different sizes, and they lack the smaller sizes below 0.4 (or sometimes 0.6) mm. Each set is different.

 

Jet Drills made in USA

Jet Drills made in USA

Set 2 China-made

Some have poorly made drills, twisted funny, bigger at the cutting end, or lumpy, varying in thickness. Some have poorly made cutting tips, so they might wander, grab and break, or not cut well.

Despite the poor quality and inexactness, the inexpensive drills are still useful for cleaning purposes, but not for measuring and maybe not for drilling. Fortunately, brass carburetor jets are the easiest thing to drill, with a drop of oil and a pilot hole already there.

 

 


Micro Drills and Wires for Sale Individually

These drills are measured at the shank (the smooth part). At the cutting edge they are 1 or 2% bigger.

These wires are steel guitar strings, cut into 5 inch lengths. 

“Metric” jets have a number that literally means hundredths of a millimeter, so a 64 jet is 0.64 mm.

Micro Drills for sale

inch   mm/#  price     moped jets that it cleans
0.011   wire     N/A Gurtner Motobecane diffuser – two idle holes (.013)
0.0135 #80  $6.00
0.0145 #79  $5.00
0.0157 0.40  $3.00 Dellorto 38 (.0162), Bing 42 (.0162)
0.016   #78  $4.00 Dellorto 40 (.0168), Bing 44 (.0167)
0.017   wire  $0.50 Dellorto 42 (.0177), Bing 46 (.0175)
0.018   #77  $3.50 Dellorto 44 (.0186), Bing 50 (.0188)
0.019   ——  $2.00 Dellorto 46 (.0194), Bing 52 (.0194)
0.0197 0.50  $2.00 Dellorto 48 (.0202), Bing 54 (.0200), “Metric” 51 (.0201)
0.0200 #76  $3.50 Dellorto 49 (.0207), Bing 56 (.0206), Gurtner 210=52 (.0210)
0.021   #75  $4.00 Dellorto 51 (.0215), Bing 58 (.0213), Gurtner 220=54 (.0220)
0.0225 #74  $5.00 Dellorto 55 (.0231), Bing 62 (.0229), Gurtner 230=56 (.0230)
0.023   ——  $2.00 Dellorto 56 (.0235), Bing 64 (.0234), Gurtner 240=58 (.0236)
0.0235 0.60  $2.00 Dellorto 58 (.0242), Bing 66 (.0239), Gurtner 245=59 (.0239)
0.0235 0.60  $1.50 Dellorto 58 (.0242), Bing 66 (.0239), Gurtner 250=60 (.0242)
0.024   #73  $3.00 Dellorto 60 (.0247), Bing 68 (.0248), “Metric” 63 (.0248)
0.025   #72  $3.50 Dellorto 62 (.0255), Bing 70 (.0254), “Metric” 65 (.0256)
0.026   #71  $4.50 Dellorto 66 (.0268), Bing 74 (.0267), “Metric” 68 (.0268)
0.0275 0.70 x N/A  Dellorto 70 (.0280), Bing 78 (.0280), “Metric” 71 (.0280)
0.028   #70  $4.00 Dellorto 72 (.0287), Bing 80 (.0287), “Metric” 73 (.0287)
0.0292 #69  $4.50 Dellorto 78 (.0306), Bing 84 (.0301), “Metric” 77 (.0303)
0.030   wire     N/A Dellorto 80 (.0312), “Metric” 79 (.0311), Gurtner K80 (.0311)
0.031   #68  $4.50 Dellorto 82 (.0318), “Metric” 81 (.0319)
0.0315 0.80  $2.00 Dellorto 84 (.0324), “Metric” 82 (.0323)
0.032   #67  $3.00 Dellorto 86 (.0331), “Metric” 84 (.0331)
0.0325  —— $2.00 Dellorto 88 (.0337), “Metric” 86 (.0339)
0.033   #66  $4.50 Dellorto 90 (.0343), “Metric” 88 (.0346)
0.034   wire     N/A “Metric” 90 (.0354)
0.035   #65  $3.00 “Metric” 92 (.0362), Gurtner MB (side mount) diffuser (.0358)
0.0354 0.90  $2.00 “Metric” 94 (.0370)
0.036   #64  $3.00
0.037   #63  $2.50
0.038   #62  $1.50
0.039   #61  $1.50
0.0394 1.00  $1.00

 


Deluxe 40-piece Micro Drill Set

Jet Drills 80-72 and 71-60

Myron’s Mopeds two case deluxe micro drill set, 80 to 72 (small) and 71 to 60 (large) plus many in-between sizes.
Price none, sorry no more.

Slide clear top plastic until hole is over drill (and pointer is on desired drill number). Only lets one drill out at a time. Never take out more than one at a time, or they can get mixed. The case keeps them organized. If any get lost, dull, or broken, individual drills can be bought at some hardware stores for $3-$4 each.

Useful for sizing to tell how big a jet really is (sometimes they’re drilled out or labeled wrong).

Useful for cleaning varnish or corrosion coating the inside of an old jet. It doesn’t really clean out any other way. The drill is used as a file, held with a needlenose pliers.

Useful for drilling jets to make a new size, as an alternative to buying ones. The drill is held with a needlenose pliers, and the jet is rotated with your fingers, with a drop of oil. To go down in size, fill the hole with solder and re-drill it smaller.

 

 

 

Here is a pin vise, a mini drill chuck, price $8

 

 

 

 

 

 

 


Other Tools for Cleaning Jets

Using a micrometer to measure a 0.017 wire

Using a micrometer to measure a 0.017″ wire

Guitar steel string 17 thousandths of an inch

Guitar string

Guitar Steel Strings in the smaller sizes are excellent tools for cleaning small holes. Here is a 0.0170 inch steel wire guitar string, perfect for cleaning out a 1974-85 Tomos stock jet size 46 that has a 0.0175 inch hole. A Honda Express NC50 (Keihin) carburetor, has a long brass idle jet tube with a tiny jet hole at the far end, too far for a drill to reach. For that, only a 2 or 3 inch piece of 0.010″ steel guitar string will reach to clean it. Ultrasonic cleaners, carb spray, or soaking are not effective for that. Other examples are a Sachs 52 jet 0.0190 would be cleaned by a 0.018″ wire, or a Motobecane 230 jet 0.023″ would be cleaned by a 0.022″ wire. The wire has to be a little smaller than the hole. Plain steel strings range from 0.008″  to 0.017″ in steps of 0.001″. Wound strings range from 0.017″ to 0.065″. 

 

Torch Tip Cleaner Set

Torch Tip Cleaner Set

Root Canal Files

Root Canal Files (say ahhh)

Welding Torch Tip Cleaners are another excellent tool for cleaning small holes. The tip has a cutting surface but not the sides. So it is made to clean the hole without widening it.

Wire Feeler Gauge Sets: There are also wire gauge measuring sets that look the same as the torch cleaner set shown.

Dentist’s Root Canal Files are also good for cleaning small holes. Color coded files range from 0.06 to 1.10 mm (0.0024 to 0.0433 inch).