Kit !

SPCK 4-bolt drivetrain kit – 27 teeth cog + Chain tensioner

Original price was: 279,02€.Current price is: 266,63€.

Our pack, SPCK 4-bolt drivetrain kit – 27 teeth cog + chain tensioner for BMX Race, brings a minimum gain of 2% on lap times and makes learning easier.

  • Select your options:
    • Kit composed of :

In stock (can be ordered)

37,49
49,99
66,58
124,96

In stock (can be ordered)

Description

SPCK 4-bolt drivetrain kit – 27 teeth cog + chain tensioner

Benefits of our SPCK 4-bolt drivetrain kit – 27 teeth cog + chain tensioner

The SPCK 4-bolt drivetrain kit – 27 teeth cog + chain tensioner pack is a definite advantage for young riders. In fact, our SPCK drivetrain brings a measured gain of between 2 and 2.8% on lap times, and makes it easier to learn to “start”, manuals… It’s currently the lightest on the market.

We offer a wide choice of size suitable for children. That’s why we recommend you take a look at our comparison table to choose the right SPCK sprocket and boost your riders’ performance.

    • Our SPCK 4-bolt drivetrain kit can be fitted to BMX bikes up to frame size “EXPERT XL”.
    • Thanks to the SPCK 27-teeth stainless steel rear sprocket and 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 bmx race parts from the SPCK range.
    • Patent pending
    • Designed and developed by AllYoogs. Made in France
  • To learn more about the concept of our chain kit, we advise you to read our article.

– The particular shape of the SPCK front sprocket, with 4 fixing bolts, is the result of an optimization by a finite element method simulation (FEM). Therefore it increases the resistance and reduces considerably weight.
        • Center distance: 104 mm – 4 bolt
        • Size : 67 to 73 teeth
        • Weight : 31 g to 35 g according to the number of teeth
Choose your SPCK 4-bolt front sprocket

– The AllYoogs front sprockets are machined in France by CNC, from 7075-T6 aluminum (more resistant than 6061 aluminium). This material guarantees lightness and especially a very high product resistance thanks to the hard anodization which gives it a golden appearance. Therefore this treatment implies a greater longevity of our products.

– The special machining of our SPCK rear sprocket, at the spline level, makes it possible to lighten it while maintaining a significant power transmission capacity. Compatible with all freewheel bodies which are a cassette type.

        • Type : rear sprocket for Single-speed cassette (single speed)
        • Size : 27 teeth
        • Weight : 26 g

Our SPCK chain tensioner fits on most BMX Race frames to ensure constant chain tension and therefore solve the recurring problems riders have been having for years. Our product is discreet, compact and designed for single speed.

Benefits of the SPCK AllYoogs chain tensioner :
  • Change the front sprocket in a few minutes, stress-free !
  • Tensioning the chain without moving the rear wheel.
  • Chain alignment is done by hand, without tools.
  • The original tensioners ensure simply the rear wheel position and no longer intervene in chain tensioning.
  • The tensioner sprocket pushes the chain up or pulls it down (push/pull), increasing the adjustment range and load capacity of the SPCK chain kit with 28 and 27-tooth rear sprockets.  Thanks to the tensioner, it will be possible to use our children’s drivetrain up to PRO frames.
  • Quick front sprocket change from 4 to 6 teeth (+2 and -2 minimum).
  • The large size of the bearing reduces its rotation speed, considerably increasing its lifetime and load capacity. It’s diameter also limits vibrations.
  •  Available in 10 mm bolt and 12, 15 and 20 mm axles
  • The lightest bmx tensioner on the market : 94g in 10″ bolt.
  • Tensioner sprocket in anti-friction and silent technical plastic.
  • The bracket fits between the frame and the wheel.
  • Completely rustproof
  • Easy to maintain and disassemble.
 

Questions about how to fit our SPCK chain tensioner? Take a look at our FAQ!

* Our chain tensioner fits all BMX frames except the following brands: Prophecy Scud Evo3, HSX carbon, GT and 4NIX

How to choose your SPCK4-bolt front sprocket with the 27-teeth cog ?

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

In the table below, retrieve the value mentioned at the intersection of the front sprocket and the rear sprocket of your child.

Example : rear sprocket = 16 and front sprocket = 37. The value to be taken into account = 376,3

CLASSIC FRONT SPROCKET 4-bolt 104 mm – TIRE 20 x 1.1/8
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 the one found in the table above (higher values). The value to be taken into consideration is the one with the smallest rear sprocket.

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

AllYoogsSPCK FRONT SPROCKET 4-bolt 104mm – TIRE 20 x 1.1/8
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 tire of 20 x 1.3/8

In the table below, retrieve the value mentioned at the intersection of the front sprocket and the rear sprocket of your child.

Example : rear sprocket = 17 and front sprocket = 39. The value to be taken into account = 386,3

CLASSIC FRONT SPROCKET 4-bolt 104 mm – TIRE 20 x 1.3/8
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 the one found in the table above (higher values). The value to be taken into consideration is the one with the smallest rear sprocket.

Example with 386,3: the closest values are 387,3 and 389,0. The smallest rear sprocket is 29, so the choice is a 29 rear sprocket with a 67 front sprocket.

AllYoogsSPCK FRONT SPROCKET 4-bolt 104mm – TIRE 20 x 1.3/8
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 particular needs (start difficulties, saturation, etc.), we can be even more precise when it comes to choosing our SPCK 4-bolt drivetrain kit – 27 teeth cog + chain tensioner. Don’t hesitate to contact us by phone or whatsapp, we’re here to help!

Additional information

Weight 0,100 kg
Dimensions 31 × 24 × 5 cm
Size

78 teeth, 79 teeth, 83 teeth

Size

27 teeth

Vis/Axes

10 mm, 12 mm, 15 mm, 20 mm

You may also like…