|
Rider Sizes and Gearing Charts for BMX racing bicycles.
Rider Size and Bike Frame Guidelines
Rider Height |
Frame Size |
Top Tube |
Stem |
Bar Rise |
Bar Width |
Cranks |
Gearing |
4'0"& under |
Micro-Mini |
15"-16" |
Mini |
2"-2.5" |
20"-22.5" |
150-160mm |
41-43/16 |
4'0"-4'6" |
Mini |
16"-17" |
Mini-Mini XL |
2"-3.5" |
21"-23.5" |
155-165mm |
41-43/16 |
4'4"-4'10" |
Junior |
17"-18.5" |
Mini XL-Pro |
3"-5" |
22"-25" |
160-175mm |
42-43/16 |
4'8"-5'4" |
Expert |
18.5"-19.5" |
Pro |
5"-7" |
25.5"-27" |
170-175mm |
42-43/16 |
5'4"-5'10" |
Pro |
20"-20.5" |
Pro-Pro XL |
7"-8" |
27"-28" |
175-180mm |
43-44/16 |
5'10"& over |
Pro XL-XXL |
20.5"& over |
Pro XL-XXL |
7"-8" |
28.5" (max) |
180-185mm |
44/16&over |
|
Crank Length Guidelines
Riders Inseam |
20" |
21" |
22" |
23" |
24" |
25" |
26" |
Crank Length |
140mm |
145mm |
150mm |
155mm |
160mm |
162mm |
166mm |
Riders Inseam |
27" |
28" |
29" |
30" |
31" |
32" |
34" |
Crank Length |
171mm |
175mm |
177mm |
180mm |
182mm |
185mm |
190mm |
|
Wheel Size for Rider Weight Guidelines
|
Max Rider Weight |
Rim Width |
|
|
Up to 65 lbs |
1.00" |
|
|
50 to 90 lbs |
1 1/8" |
|
|
85 to 120 lbs |
1 3/8" |
|
|
115 to 150 lbs |
1.50" |
|
|
140 lbs and Up |
1.75" |
|
|
Rear Tire Size and Rollout in Inches (varies with Brand, model)
|
20" X 1.75" GEAR CHART |
Chain wheels |
34 |
35 |
36 |
37 |
38 |
39 |
40 |
41 |
42 |
43 |
44 |
45 |
46 |
Freewheel 14 |
47.4 |
48.7 |
50.2 |
51.6 |
53.0 |
54.4 |
55.7 |
57.1 |
58.5 |
59.9 |
61.9 |
62.7 |
64.1 |
Freewheel 15 |
44.3 |
45.4 |
46.0 |
48.1 |
49.4 |
50.7 |
52.0 |
53.3 |
54.6 |
55.9 |
57.2 |
58.5 |
59.8 |
Freewheel 16 |
41.5 |
42.7 |
43.6 |
45.1 |
46.3 |
47.5 |
48.8 |
50.0 |
51.2 |
52.4 |
53.7 |
54.9 |
56.1 |
Freewheel 17 |
39.0 |
40.2 |
41.3 |
42.5 |
43.6 |
44.7 |
45.9 |
47.0 |
48.2 |
49.4 |
50.5 |
51.7 |
52.8 |
Freewheel 18 |
36.8 |
37.8 |
39.0 |
40.1 |
41.2 |
42.3 |
43.3 |
44.4 |
45.5 |
46.6 |
47.7 |
48.8 |
49.9 |
|
|
20" X 1.50" GEAR CHART |
Chain wheels |
34 |
35 |
36 |
37 |
38 |
39 |
40 |
41 |
42 |
43 |
44 |
45 |
46 |
Freewheel 14 |
46.8 |
48.1 |
49.5 |
50.9 |
52.3 |
53.6 |
55.0 |
56.4 |
57.5 |
59.1 |
60.5 |
61.8 |
63.2 |
Freewheel 15 |
43.6 |
44.9 |
46.2 |
47.4 |
48.8 |
50.1 |
51.3 |
52.8 |
53.9 |
55.2 |
56.5 |
57.7 |
59.1 |
Freewheel 16 |
40.9 |
42.1 |
43.3 |
44.5 |
45.7 |
46.9 |
48.1 |
49.3 |
50.5 |
51.7 |
52.9 |
54.1 |
55.3 |
Freewheel 17 |
38.5 |
39.6 |
40.8 |
41.9 |
43.1 |
44.1 |
45.2 |
46.4 |
47.5 |
48.7 |
49.8 |
51.0 |
52.2 |
Freewheel 18 |
36.4 |
37.4 |
38.5 |
39.6 |
40.6 |
41.7 |
42.8 |
43.9 |
44.9 |
46.0 |
47.0 |
48.1 |
49.2 |
|
|
20" x 1 3/8" GEAR CHART |
Chain wheels |
34 |
35 |
36 |
37 |
38 |
39 |
40 |
41 |
42 |
43 |
44 |
45 |
46 |
Freewheel 14 |
51.0 |
52.5 |
54.0 |
55.5 |
57.0 |
58.5 |
60.0 |
61.5 |
63.0 |
64.5 |
66.0 |
67.5 |
69.0 |
Freewheel 15 |
47.6 |
49.0 |
50.4 |
51.6 |
53.2 |
54.6 |
56.0 |
57.4 |
58.8 |
60.2 |
61.6 |
63.0 |
64.4 |
Freewheel 16 |
44.6 |
45.9 |
47.3 |
48.6 |
49.9 |
51.2 |
52.5 |
53.9 |
55.2 |
56.5 |
57.8 |
59.1 |
60.4 |
Freewheel 17 |
42.0 |
43.2 |
44.5 |
45.7 |
47.0 |
48.2 |
49.4 |
50.7 |
51.9 |
53.2 |
54.4 |
55.6 |
56.9 |
Freewheel 18 |
39.7 |
40.7 |
42.0 |
43.2 |
44.4 |
45.5 |
46.7 |
47.9 |
49.0 |
50.2 |
51.4 |
52.5 |
53.7 |
|
|
20" X 1 1/8" GEAR CHART |
Chain wheels |
34 |
35 |
36 |
37 |
38 |
39 |
40 |
41 |
42 |
43 |
44 |
45 |
46 |
Freewheel 14 |
48.6 |
50.0 |
51.4 |
52.8 |
54.3 |
55.7 |
57.1 |
58.6 |
60.0 |
61.4 |
62.8 |
64.3 |
65.7 |
Freewheel 15 |
45.3 |
46.7 |
48.0 |
49.3 |
50.7 |
52.0 |
53.3 |
54.7 |
56.0 |
57.3 |
58.7 |
60.0 |
61.3 |
Freewheel 16 |
42.5 |
43.8 |
45.0 |
46.2 |
47.5 |
48.7 |
50.0 |
51.2 |
52.5 |
53.7 |
55.0 |
56.2 |
57.5 |
Freewheel 17 |
40.0 |
41.2 |
42.3 |
43.5 |
44.7 |
45.9 |
47.0 |
48.2 |
49.4 |
50.6 |
51.8 |
52.9 |
54.1 |
Freewheel 18 |
37.7 |
38.8 |
40.0 |
41.1 |
42.2 |
43.3 |
44.4 |
45.6 |
46.7 |
47.8 |
48.9 |
50.0 |
51.1 |
|
|
24" X 1.75" GEAR CHART (Cruiser) |
Chain wheels |
34 |
35 |
36 |
37 |
38 |
39 |
40 |
41 |
42 |
43 |
44 |
45 |
46 |
Freewheel 14 |
58.3 |
60.0 |
61.7 |
63.3 |
65.0 |
66.9 |
68.6 |
70.3 |
72.0 |
73.7 |
75.3 |
77.0 |
78.9 |
Freewheel 15 |
54.4 |
56.0 |
57.6 |
59.3 |
60.7 |
62.4 |
64.1 |
65.5 |
67.2 |
68.9 |
70.3 |
72.0 |
73.7 |
Freewheel 16 |
51.0 |
52.5 |
54.0 |
55.5 |
57.0 |
58.5 |
60.0 |
61.4 |
63.1 |
64.5 |
66.0 |
67.4 |
69.1 |
Freewheel 17 |
48.0 |
49.4 |
50.0 |
52.2 |
53.6 |
55.1 |
56.5 |
57.9 |
59.3 |
60.7 |
62.1 |
63.6 |
65.0 |
Freewheel 18 |
45.3 |
46.5 |
48.0 |
49.4 |
50.7 |
52.0 |
53.3 |
54.7 |
56.0 |
57.3 |
58.5 |
60.0 |
61.4 |
|
|
24" X 1 1/8" GEAR CHART (Cruiser) |
Chain wheels |
34 |
35 |
36 |
37 |
38 |
39 |
40 |
41 |
42 |
43 |
44 |
45 |
46 |
Freewheel 14 |
54.9 |
56.5 |
58.1 |
59.7 |
61.3 |
63.1 |
64.7 |
66.3 |
67.9 |
69.4 |
71.0 |
72.6 |
74.4 |
Freewheel 15 |
51.3 |
52.8 |
54.3 |
55.8 |
57.3 |
58.8 |
60.3 |
61.8 |
63.3 |
64.9 |
66.3 |
67.9 |
69.4 |
Freewheel 16 |
48.1 |
49.5 |
50.9 |
52.3 |
53.7 |
55.1 |
56.6 |
57.9 |
59.5 |
60.8 |
62.2 |
63.9 |
65.1 |
Freewheel 17 |
45.2 |
46.6 |
47.9 |
49.3 |
50.6 |
51.9 |
53.2 |
54.6 |
55.9 |
57.2 |
58.6 |
59.9 |
61.3 |
Freewheel 18 |
42.7 |
43.9 |
45.2 |
46.6 |
47.7 |
49.1 |
50.3 |
51.5 |
52.8 |
54.0 |
55.3 |
56.6 |
57.9 |
|
