Where to have motorcycle cylinder bored?

Here's where to get a motorcycle cylinder bored, with key considerations for choosing the right service:

1. Motorcycle-Specific Machine Shops
Specialization: Shops focusing only on bikes understand nuances like Nikasil coatings, vintage tolerances, or performance builds.
Advantage: Correct tooling for small-bore cylinders and experience with common engine models.
Find them: Ask local racing teams, custom builders, or dealership mechanics for referrals.

2. Automotive Machine Shops (Selective Use)
When viable: For simple iron-lined cruiser/touring cylinders where motorcycle-specific shops are unavailable.
Risk: Many lack experience with aluminum blocks, plated bores, or tight tolerances needed for high-RPM engines.
Verify: Confirm they've handled motorcycle cylinders before and use precision boring bars.

3. Engine Rebuild Specialists
Ideal for: Complex jobs like overboring a multi-cylinder block or matching port work.
Perk: Often offer "while-you-wait" services and inspect related parts (pistons, heads) for compatibility.
Common in: Racing hubs or cities with a strong car/bike culture.

4. OEM Dealer Service Centers
When to use: For warranty work or if retaining factory specifications is critical.
Limitation: Typically replaces cylinders instead of boring them; costly for performance upgrades.

5. Postal/Mail-In Services
Best for: Rare engines, coated cylinders, or high-precision work requiring niche expertise.
Pros: Access to top specialists nationwide.
Cons: Shipping risks (damage, loss), no face-to-face quality checks.