Frequently Asked Questions
Q: How much does the service cost?
A: Services are billed on a per-task basis. See our services and pricing tab for per-task labor cost. Each repair task has its own price multiplied by the number of times it is performed on a given part. Example: Valve seat cut is $25 per seat, thus 4 seats = $100 ($25 × 4). Each cylinder head may need a different number of services depending on wear, determined after Phase 1 evaluation.
Q: Do I need to take my head apart before I send it to you?
A: For cylinder heads, we only need the head casting with valves still installed. Remove all other parts: camshafts, rocker arms, rocker box, dowel pins, intake manifolds, tappet adjuster covers, and cam chain tensioner parts.
Q: Can I mail it to you first for the evaluation?
A: No, you must purchase our Phase 1 cleaning & inspection service before we can evaluate any parts.
Q: What if I have my own new/replacement/used parts (valves/guides)?
A: Only genuine CMC parts are used for any service work, as we can guarantee quality and consistency. We cannot use customer-supplied parts. Many aftermarket parts are of questionable fit or quality. Phase 1 inspection determines exactly which parts are required.
Q: Do you fix or weld broken cooling fins, gouged surfaces, pitting from corrosion, or worn bearing journals?
A: No, our shop is not equipped for those repairs.
Q: What gets done/replaced during the rebuild process? What parts get reused?
A: Typical work includes re-cutting valve seats and lapping the head gasket surface. Valve guides may be reused if within service limits; if worn, they are bronze-lined. All threads are chased clean. Valve springs and hardware are reused and shimmed as needed.
Q: What if my head is not rebuildable?
A: We will contact you to discuss alternatives. We may be able to source a suitable replacement part.
Q: Can I choose only some of the quoted processes and skip others?
A: Our goal is to do only the minimal work needed to bring your part back into specification—no more, no less.
Q: Why do I need to pay for services up front?
A: To ensure there are no surprises for anyone involved.
Q: I live internationally. Can I use this service?
A: Yes, as long as you are willing to pay international shipping costs.
Q: Is there a warranty on parts and labor?
A: We stand behind our work, but each warranty claim is case-by-case. Many factors can cause issues (defective part, machining error, improper assembly, etc.). You have 60 days from receipt to install and test your part.
Q: My bike is outside your supported models. Will you do machine work for me?
A: No.
Q: What if my part is already in good shape and doesn’t need major service?
A: If a head is in great shape, we may only perform minimal work (level the gasket surface, lap valves/seats). We do not perform unnecessary work.
Q: Can I reuse or touch up original Honda valves?
A: No. Original Honda valves are soft alloy with a thin Stellite coating. Grinding through it leaves a weak core that will fail quickly and could cause catastrophic engine damage. We always replace valves during a rebuild.
Q: Do you replace valve stem seals?
A: Yes, if your engine originally used them. Not all models use seals, and some only use them on certain valves.
Q: Can you repair stripped threads, spark plug holes, or remove broken bolts?
A: Most of the time, yes. Broken bolt repairs are quoted case by case.
Q: Do you replace valve seats?
A: No. We only machine the existing seats back to proper shape, finish, and angles.
Q: Do you do a 3-angle valve job?
A: Yes, we cut 30°/45°/60° seat angles.
Q: Do you replace valve guides?
A: Only as needed. Our preferred method is to bore and install a bronze liner. We only install a new guide if the original is missing, broken, or unsuitable for a sleeve.
Q: Why does CMC restore rather than swap out valve guides?
A: Replacing guides is more labor-intensive, costlier, and can damage the casting or misalign the valve to seat, requiring more machining. Our approach is minimally invasive to allow future rebuilds.
Q: Do you replace valve springs?
A: No. Valve springs are almost always reusable. We shim them to restore preload. Note: CB450 torsion bar springs cannot be shimmed.
Q: At what mileage should top-end service/inspection be performed?
A: Motorcycle mileage wears parts faster than cars—roughly a 5:1 ratio. A 30,000-mile bike is like a 150,000-mile car. Service intervals assume proper care with regular oil changes and adjustments; many engines need service sooner. Approximate intervals:
- CT90 / S90 / CL90 = < 8,000 miles
- CB175 / CL175 / CB200 = 12,000–15,000 miles
- CB350 / CL350 / SL350 = 18,000–20,000 miles
- CB360 / CL350 / CJ360 = 18,000–20,000 miles
- CB450 / CL450 / CB500T = 25,000–30,000 miles
- CB500K / CB550 K & F = 25,000–30,000 miles
