16603-72 Top Quality Milled Cylinder Base Hardware
incl. VAT
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Iron City Dealer
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Specifications
- Brand
- Colony
- Part Number
- 231601
- OEM Reference
- 16603-72
- Pack Quantity
- Each
- Category
- Cylinder Hardware
- VAT Rate
- 20%
About This Product
Give your Sportster the strength it needs with this milled cylinder base hardware from Colony. These nuts and washers are machined from high-grade steel to provide maximum durability and a secure fit for your cylinders. Designed specifically for Sportster models, this hardware replaces OEM 16603-72 and is sold as a complete set. In the high-vibration environment of an Evolution or Ironhead engine, having top-tier fasteners is essential for maintaining a proper seal at the cylinder base. Colony's reputation for producing the strongest hardware on the market means you can trust these parts for both daily riding and performance applications, ensuring your top end remains secure and professional in appearance.
Fitment
28 modelsSportster
Sportster 28 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 1970 | 3AH0 Sportster Standard (1970) 3AH0 XLH Sportster Standard (1970) Sportster Standard XLH 3AH0 XLH-1000 |
| Harley-Davidson | 1971 | 3AH1 Sportster Standard (1971) 3AH1 XLH Sportster Standard (1971) Sportster Standard XLH 3AH1 XLH-1000 |
| Harley-Davidson | 1972 | 3AH2 Sportster Standard (1972) 3AH2 XLH Sportster Standard (1972) Sportster Standard XLH 3AH2 XLH-1000 |
| Harley-Davidson | 1973 | 3AH3 Sportster Standard (1973) 3AH3 XLH Sportster Standard (1973) Sportster Standard XLH 3AH3 XLH-1000 |
| Harley-Davidson | 1974 | 3AH4 Sportster Standard (1974) 3AH4 XLH Sportster Standard (1974) Sportster Standard XLH 3AH4 XLH-1000 |
| Harley-Davidson | 1975 | 3AH5 Sportster Standard (1975) 3AH5 XLH Sportster Standard (1975) Sportster Standard XLH 3AH5 XLH-1000 |
| Harley-Davidson | 1976 | 3AH6 Sportster Standard (1976) 3AH6 XLH Sportster Standard (1976) Sportster Standard XLH 3AH6 XLH-1000 |
| Harley-Davidson | 1977 | 3AH7 Sportster Standard (1977) 3AH7 XLH Sportster Standard (1977) Sportster Standard XLH 3AH7 XLH-1000 |
| Harley-Davidson | 1978 | 3AH8 Sportster Standard (1978) 3AH8 XLH Sportster Standard (1978) Sportster Standard XLH 3AH8 XLH-1000 |
| Harley-Davidson | 1979 | 3AH9 Sportster 1000 (1979) 3AH9 XLH1000 Sportster 1000 (1979) Sportster 1000 XLH1000 3AH9 XLH-1000 |
| Harley-Davidson | 1980 | 3AJ0 Sportster 1000 (1980) 3AJ0 XLH1000 Sportster 1000 (1980) Sportster 1000 XLH1000 3AJ0 XLH-1000 |
| Harley-Davidson | 1970 | 4AH0 Sportster 1000 (1970) 4AH0 XLCH1000 Sportster 1000 (1970) Sportster 1000 XLCH1000 4AH0 XLCH-1000 |
| Harley-Davidson | 1971 | 4AH1 Sportster 1000 (1971) 4AH1 XLCH1000 Sportster 1000 (1971) Sportster 1000 XLCH1000 4AH1 XLCH-1000 |
| Harley-Davidson | 1972 | 4AH2 Sportster 1000 (1972) 4AH2 XLCH1000 Sportster 1000 (1972) Sportster 1000 XLCH1000 4AH2 XLCH-1000 |
| Harley-Davidson | 1973 | 4AH3 Sportster 1000 (1973) 4AH3 XLCH1000 Sportster 1000 (1973) Sportster 1000 XLCH1000 4AH3 XLCH-1000 |
| Harley-Davidson | 1974 | 4AH4 Sportster 1000 (1974) 4AH4 XLCH1000 Sportster 1000 (1974) Sportster 1000 XLCH1000 4AH4 XLCH-1000 |
| Harley-Davidson | 1975 | 4AH5 Sportster 1000 (1975) 4AH5 XLCH1000 Sportster 1000 (1975) Sportster 1000 XLCH1000 4AH5 XLCH-1000 |
| Harley-Davidson | 1976 | 4AH6 Sportster 1000 (1976) 4AH6 XLCH1000 Sportster 1000 (1976) Sportster 1000 XLCH1000 4AH6 XLCH-1000 |
| Harley-Davidson | 1977 | 4AH7 Sportster 1000 (1977) 4AH7 XLCH1000 Sportster 1000 (1977) Sportster 1000 XLCH1000 4AH7 XLCH-1000 |
| Harley-Davidson | 1978 | 4AH8 Sportster 1000 (1978) 4AH8 XLCH1000 Sportster 1000 (1978) Sportster 1000 XLCH1000 4AH8 XLCH-1000 |
| Harley-Davidson | 1979 | 4AH9 Sportster (1979) 4AH9 XLCH Sportster (1979) Sportster XLCH 4AH9 XLCH-1000 |
| Harley-Davidson | 1980 | 4AJ0 Sportster 1000 (1980) 4AJ0 XLCH1000 Sportster 1000 (1980) Sportster 1000 XLCH1000 4AJ0 |
| Harley-Davidson | 1981–1984 | SPORTSTER XLS |
| Harley-Davidson | 1983–1984 | SPORTSTER XR-1000 |
| Harley-Davidson | 1983–1984 | SPORTSTER XLX |
| Harley-Davidson | 1959 | Sportster (1959) Sportster SL |
| Harley-Davidson | 1959 | Sportster (1959) Sportster SLH |
| Harley-Davidson | 1981–1984 | Sportster 1100 (1987) CANH XLH1100 Sportster 1100 (1987) Sportster 1100 XLH1100 CANH |
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