SPCK BMX 4-bolt front sprocket

SPCK 4-bolt front sprocket – Kids BMX Race drivetrain - AllYoogs

SPCK BMX 4-bolt front sprocket

49,99€

BMX CHILDREN’S PARTS – tracks

The SPCK BMX 4-bolt front sprocket is ultra light, a definite advantage for the performance of your young riders (kids).

    • Centre distance : 104 mm – 4-bolt fixing for reduced chain pitch
    • Size : 67 to 73 teeth
    • Weight : 31 g to 35 g depending on the number of teeth
    • Colour : golden
    • Material : 7075 aluminium
    • Surface treatment: hard anodised

Choose your SPCK front sprocket

SKU: BPDFSPCK400EN Categories: , , , Tags: , Brand:
SPCK 4-bolt chain kit - BMX Race - AllYoogs
SPCK BMX 4-bolt chain Kit
139,99€ TTC
SPCK 4-bolt drivetrain kit + tools - BMX Race - AllYoogs
SPCK 4-bolt drivetrain kit + tools
219,95€ IVA incl.
SPCK 4-bolt drivetrain kit + tools + chain tensioner - BMX Race - AllYoogs
SPCK 4-bolt drivetrain kit + tools + chain tensioner
359,99€ incl. VAT

Description

BMX 4-bolt SPCK chainring: optimized performance & lightness

The BMX SPCK 4-bolt front sprocket for children features an advanced design, developed through numerical mechanical simulation (FEM). Thanks to this technology, it offers increased resistance while significantly reducing weight.

AllYoogs® SPCK 4-bolt front sprocket are CNC-machined in France from 7075 aluminum, a material stronger than 6061 aluminum. Combined with hard anodization, it ensures maximum lightness and exceptional durability, extending the product’s lifespan.

A Chain Kit Designed for Performance

The SPCK chain kit is a real asset for young riders. Its innovative drivetrain delivers a minimum measured time gain of 2.4 to 2.8%, while making it easier to learn starts, manuals, and other essential techniques. It is currently the lightest on the market.

Compatibility & Technical Limits

  • Our SPCK 4-bolt front sprocket can be fitted to BMX bikes up to frame size “EXPERT” (weight limit 45kg = 99lb).
  • Thanks to the SPCK chain tensioner, it is possible to push the limits of our kit up to “PRO” frames (weight limit 50kg = 110lb).
  • The SPCK chain kit is only compatible with SPCK race parts.
  • Patent Pending
  • Designed and developed by AllYoogs. Made in France

Choose the Perfect Configuration

Finally, we offer a wide range of sprocket sizes tailored for children, helping them optimize their performance on the track. To go further, check out our development tables to select the ideal SPCK chainring.

Choose your SPCK front sprocket

💡For more details on our chain kit concept, we recommend reading our article.
If you need more information on installation and maintenance BMX chain kit, you’ll find answers to your questions in our FAQ.

Follow us on social networks

How to choose your BMX 4-bolt front sprocket ?​

  1.  Development calculated in mm with a 20 x 1.1/8 tyre

  2.  Development calculated in mm with a 20 x 1.3/8 tyre

1.  Development calculated in mm with a 20 x 1.1/8 tyre

In the table below, find the value indicated at the intersection of the front sprocket and the cog of your child.

Example: cog = 16 and front sprocket = 37. The value to take into account = 376,3

CLASSIC FRONT SPROCKET 4-bolt 104 mm – 20 x 1.1/8 TYRE
REAR SPROCKET323334353637
38
39404142434445
18289,3298,3307,4316,4325,5334,5343,6352,6361,6370,7379,7388,8397,8 406,8
17306,3315,9325,5335,0344,6354,2363,8373,3382,9
392,5402,0411,6421,2 430,8
16325,5335,6345,8356,0
366,2376,3386,5396,7406,8417,0427,2437,3447,5457,7
15347,2358,0368,9379,7390,6401,4412,3423,1434,0444,8455,7

To obtain the SPCK equivalence :

In the table, find the values closest to those in the table above (higher values). The value to be taken into account is the one with the smallest cog.

Example with 376,3: the closest values are 378 and 379,7. The smallest cog is 30 with a 70 front sprocket.

AllYoogsSPCK FRONT SPROCKET 4-bolt 104mm – 20 x 1.1/8 TYRE
SPCK REAR SPROCKET67686970717273
34320,7325,5330,3335,0339,8344,6349,4
33330,4335,3340,3345,2350,1355,1360,0
32340,7345,8350,9356,0361,1366,2371,2
31351,7357,0362,2
367,5372,7
378,0383,2
30363,4368,9374,3
379,7385,1390,6396,0
29376,0381,6387,2
392,8398,4404,0409,6
28389,4395,2401,0406,8412,6418,5424,3
27403,8409,8415,9421,9427,9434,0440,0

 
 
 

2.  Development calculated in mm with a 20 x 1.3/8 tyre

In the table below, find the value indicated at the intersection of the front sprocket and the cog of your child.

Example: rear sprocket = 16 and front sprocket = 40. The value to take into account = 421

CLASSIC FRONT SPROCKET 4-bolt 104 mm – 20 x 1.3/8 TYRE
REAR SPROCKET323334353637
38
39404142434445
18299,4308.7318.1327.4336.8346.1355.5364.8374.2383.6392.9402.3411.6421,0
17317.0326.9336.8346.7356.6366.5376.4386.3396.2406.1416.0425.9435.8445,7
16336.8347.3357.8368.4378.9389.4399.9410.4421.0431.5442.0452,5463,1473,6
15359.2370.5381.7392.9404.1415.4426.6437.8449,0460,3471,5

To obtain the SPCK equivalence :

In the table, find the values closest to those in the table above (higher values). The value to be taken into account is the one with the smallest cog.

Example with 421: the closest values are 423,9 and 424,1. The smallest cog is 27 with a 68 front sprocket.

AllYoogsSPCK FRONT SPROCKET 4-bolt 104mm – 20 x 1.3/8 TYRE
SPCK REAR SPROCKET67686970717273
34331.8336.8341.7346.7351.6356.6361.5
33341.9347.0352.1357.2362.3367.4372.5
32352.6357.8363.1368.4373.6378.9384.1
31363.9369.4374.8380.2385.7391.1396.5
30376.1381.7387.3392.9398.5404.1409.7
29389.0394.8400.7406.5412.3418.1423.9
28402.9408.9415.0421.0427.0433.0439.0
27417,9424,1430,3436,6442,8449,0455,3

 

Depending on your child’s particularities (difficulty in starting, saturation…), we can be even more precise in the choice of our SPCK chain kit. Don’t hesitate to contact us by phone or whatsapp, we are here to help you!

Additional information

Weight 0,067 kg
Dimensions 27 × 20 × 1 cm
Size

67 teeth, 68 teeth, 69 teeth, 70 teeth, 71 teeth, 72 teeth, 73 teeth, 74 teeth, 76 teeth, 75 teeth

You may also like…

Related products