Bolt-on cylinder kit and method for increasing the displacement of an engine

Patent metadata

Field	Value
Publication number	US-10247128-B2
Application number	US-201715697038-A
Country	US
Kind code	B2
Filing date	Sep 6, 2017
Priority date	Mar 31, 2015
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

A cylinder for a V-twin engine includes a section of steel tubing cut to a length. The section of steel tubing includes a first portion having a first wall thickness and a second portion having a second wall thickness less than the first wall thickness. The second wall thickness is less than 0.050 inch. The section of steel tubing includes a first ribbing pattern on an outer surface, within the first portion, and a second ribbing pattern including multiple ribs formed on individual ribs of the first ribbing pattern. A cast body is provided on the first portion of the section of steel tubing so that the section of steel tubing is fixedly secured within the body to form a cylinder sleeve defining a cylinder bore. The second portion having the second wall thickness extends from an end of the body to be received within a bore of a crankcase.

First claim

What is claimed is:

1. A cylinder for a V-twin engine, the cylinder manufactured by a process comprising:
providing a section of steel tubing;
cutting the section of steel tubing to length;
machining the section of steel tubing in a subtractive process, including
forming a first portion having a first wall thickness and a second portion having a second wall thickness less than the first wall thickness, wherein the second wall thickness is less than 0.050 inch, and
forming a first ribbing pattern, including a radially outward protruding rib, on a radially outer surface of the section of steel tubing within the first portion, and forming a second ribbing pattern on the radially outer surface of the section of steel tubing within the first portion, wherein the first ribbing pattern is a larger, primary ribbing pattern and the second ribbing pattern is a smaller, secondary ribbing pattern whereby multiple radially outward protruding ribs of the second ribbing pattern are provided within the radially outward protruding rib of the first ribbing pattern; and

casting a body onto the first portion of the section of steel tubing so that the section of steel tubing is fixedly secured within the body to form a cylinder sleeve defining a cylinder bore, wherein the second portion having the second wall thickness extends from an end of the body to be received within a bore of a crankcase.

2. The cylinder of claim 1 , wherein the body includes an exterior surface having a plurality of fins.

3. The cylinder of claim 1 , wherein the body is solid, having no internal voids or cooling jackets for cooling liquid.

4. The cylinder of claim 1 , wherein the body further includes a flange proximate the end, the flange defining a surface configured to about a surface of the crankcase, and a plurality of mounting holes extending from the surface through the body.

5. The cylinder of claim 1 , wherein a diameter of the cylinder bore is greater than 3.948 inches.

6. The cylinder of claim 1 , wherein a diameter of the cylinder bore is about 4.000 inches.

7. The cylinder of claim 6 , wherein the outer diameter of the second portion is about 4.068 inches.

8. The cylinder of claim 1 , wherein the cylinder sleeve is constructed from SAE grade 4140 steel.

9. The cylinder of claim 1 , wherein the second wall thickness is less than 0.040 inches and greater than 0.025 inch.

10. The cylinder of claim 1 , wherein the second wall thickness is between 0.033 inch and 0.035 inch.

11. The cylinder of claim 1 , wherein at least one of the first and second ribbing patterns is helical.

12. The cylinder of claim 1 , wherein the first and second ribbing patterns are formed in intersecting helical patterns having opposite axial components in a given circumferential direction.

13. A cylinder for a V-twin engine, the cylinder comprising:
a section of steel tubing cut to a length, the section of steel tubing including
a first portion having a first wall thickness and a second portion having a second wall thickness less than the first wall thickness, wherein the second wall thickness is less than 0.050 inch,
a first ribbing pattern, including a radially outward protruding rib, on a radially outer surface of the section of steel tubing within the first portion, and
a second ribbing pattern on the radially outer surface of the section of steel tubing within the first portion, wherein the first ribbing pattern is a larger, primary ribbing pattern and the second ribbing pattern is a smaller, secondary ribbing pattern whereby multiple radially outward protruding ribs of the second ribbing pattern are provided within the radially outward protruding rib of the first ribbing pattern; and

a cast body provided on the first portion of the section of steel tubing so that the section of steel tubing is fixedly secured within the body to form a cylinder sleeve defining a cylinder bore, wherein the second portion having the second wall thickness extends from an end of the body to be received within a bore of a crankcase.

14. The cylinder of claim 13 , wherein the cast body includes an exterior surface having a plurality of fins.

15. The cylinder of claim 13 , wherein the cast body is solid, having no internal voids or cooling jackets for cooling liquid.

16. The cylinder of claim 13 , wherein the cast body further includes a flange proximate the end, the flange defining a surface configured to about a surface of the crankcase, and a plurality of mounting holes extending from the surface through the cast body.

17. The cylinder of claim 13 , wherein a diameter of the cylinder bore is greater than 3.948 inches.

18. The cylinder of claim 13 , wherein a diameter of the cylinder bore is about 4.000 inches.

19. The cylinder of claim 18 , wherein the outer diameter of the second portion is about 4.068 inches.

20. The cylinder of claim 13 , wherein the cylinder sleeve is constructed from SAE grade 4140 steel.

21. The cylinder of claim 13 , wherein the second wall thickness is less than 0.040 inches and greater than 0.025 inch.

22. The cylinder of claim 13 , wherein the second wall thickness is between 0.033 inch and 0.035 inch.

23. The cylinder of claim 13 , wherein at least one of the first and second ribbing patterns is helical.

24. The cylinder of claim 13 , wherein the first and second ribbing patterns are formed in intersecting helical patterns having opposite axial components in a given circumferential direction.

Assignees

• Harley Davidson Motor Co Inc

Inventors

• Nicosia Tony
• Bishop Brad
• Dane Mark

Classifications

• F02B61/02

  for driving cycles · CPC title

• F02F1/004 Primary

  Cylinder liners (F02F1/08, F02F1/16 take precedence) · CPC title

• F02F1/08

  running-liner and cooling-part of cylinder being different parts or of different material · CPC title

• F02B75/22

  with cylinders in V, fan, or star arrangement · CPC title

• F02F1/00

  Cylinders; Cylinder heads · CPC title