Here are a series of stories that we feel should be interesting to you, the consumer, that we have ran across and have solutions for common problems encountered by other people. Covering a verity of machines both 2 and 4 stroke you may find some answers to problems possibly encountered by yourself. If you would like to share any personal experiences that you might feel would help other riders, let us know and we’ll pass the information on, weather it is here on the Shop Talk page.

CRF’s TRX’es YZF’s and YFZ Riders

Having to tow your 1 or 2-year-old machine to bump start it? Taking it back to the dealer for repairs. Getting it back, and having it only run for a hand full of hours before you run into the same situation again? This is becoming a common problem. What’s happening is, the newer machines are using the lightweight titanium valves, good for performance (less valve train weight) but longevity is sacrificed. Some of these valves are only rated for a 20-hour life. These valves have an oxide coating. Once this oxide coating wares through to the titanium, the valve is shot. If you have to set the valve lash, the valve is done, shot, gone. This is what the dealers do, they reset the valve lash, for $135.00 and up, it runs for several hours then your back to square one. The fix is to replace the valves. Another problem we are seeing a fair amount of is, the tulip is separating from the stem. The reason for this is these new titanium valves are 2 piece. If this should happen, when is usually does, during high RPM’s, your looking at around a $3000.00 repair. You have a choice in repairs…you can use stock factory replacement valves, or you can use our new T2 valves. Our T2 valves are a one-piece stainless steel valve with a black nitroneg coating. These valves require a spring kit because of the difference in weight. In our opinion it is worth the added weight to assure longevity and reliability. These new 4-stroke machines are far more expensive to repair then the 2-strokes. Keep this in mind if you would happen to here about, or run into these problems yourself.
Honda 400EX Owners

The Honda 400EX, a popular and well-liked machine, one of the most asked for upgrades are the 440 big bore kit. The most common complaint that we are questioned about is head gasket failure. This is what we are finding…The sleeve that is installed is not properly set, this allows the crown of the sleeve to move when the head is tourqed. Another problem is the cylinder stud threads are compromised, and fail. Both of these cause head gasket failure. This is easy to see, inspect the head gasket, find the point of leakage, link it to a loose cylinder stud or, a difference in sleeve to cylinder height, you can feel this by running your fingernail across the two surfaces.
  • Aluminum Welding
  • Boring
  • Sleeving
  • 4 Stroke Specialist
  • Porting 2 & Stroke
  • Race Tech Suspension

EST 1986

Phone: 570-339-5898

Prices subject to change without notice.

Advanced Machining Services LLC

5 Main St.
Mount Carmel, PA 17851

Monday thru Friday 9:00 to 5:30 EST
Closed Saturday and Sunday


Building performance engines since 1986

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