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Top End Rebuild Kit MC21/28, Cyl B Assy. 1

Below is everything you need to do a top end rebuild on your MC21/28. One kit includes all parts for one cylinder (cylinder 'B'). To overhaul both cylinders please order 2 kits.

There are different kits depending on the piston supplied and the pistons are sized to match the cylinder. The cylinders have a letter stamped on them. A cylinder = B piston  B cylinder = no mark piston, C cylinder = D piston. The largest cylinder bore is A and the smallest is C. However, note that this is only for when cylinders are new or in good condition, so if the cylinder is worn, the corresponding piston will be a looser so a bigger piston might be advised. If the cross hatch honing of the cylinder is very feint then we suggest using the next size up piston. The differences in sizes are tiny (11 microns between largest and smallest) and for the most part not an issue so it is not a problem if a smaller piston is used in a larger cylinder or the other way round.


Cylinder A = 54.008mm – 54.011mm        use         Piston B = 53.966mm – 53.969mm

Cylinder B = 54.004mm – 54.008mm        use         Piston # = 53.962mm – 53.965mm

Cylinder C = 54.000mm – 54.004mm        use         Piston D = 53.958mm – 53.961mm


Piston to bore clearance = 0.039mm - 0.045mm


This product contains the following items:
Gasket, Cylinder, MC16~281 x  (12192-KV3-680) Gasket, Cylinder, MC16~28 $7.38US
Gasket, Head, MC21/281 x  (12251-KV3-830) Gasket, Head, MC21/28 $15.43US
Piston Ring, MC16~281 x  (13010-KV3-305) Piston Ring, MC16~28 $55.12US
Piston No mark, MC21/281 x  (13103-KV3-830) Piston No mark, MC21/28 $86.80US
Piston Pin MC18~281 x  (13111-KV3-771) Piston Pin MC18~28 $15.33US
RC Valve Shaft E Clip, MC281 x  (90601-KV3-000) RC Valve Shaft E Clip, MC28 $2.13US
Bearing, Piston, MC281 x  (91102-KV3-771) Bearing, Piston, MC28 $9.41US
Seal, RC Valve Shaft, MC281 x  (91201-PA9-004) Seal, RC Valve Shaft, MC28 $3.47US
Dowel, Cylinder, MC282 x  (94301-10160) Dowel, Cylinder, MC28 $1.02US
Piston Circlip 15mm, MC16~282 x  (94601-15000) Piston Circlip 15mm, MC16~28 $0.60US

Cost of separate parts: $198.32US

You save $2.07US
9 in Stock
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