WHAT IS IT? The TM Designworks GP motocross rear chain guide is an upgraded version of TM Designworks’ already five-star-rated guide.
WHAT’S IT COST? $79.00 (for late-model Japanese motocross bikes).
CONTACT? (541) 772-4161 or www.tmdesignworks.com.
WHAT STANDS OUT? Here’s a list of things that stand out with TM Designworks’ GP rear chain guide.
(1) Improved design. This chain guide was built strictly for motocross-minded riders. There have been many upgrades to the GP guide compared to the original TM guide. (a) The body of the guide has been narrowed to reduce the chance of rubbing against ruts or berms.
(b) Clamping strength to the swingarm has been increased. (c) The wear-pad chain-line angle and length have been changed to prevent premature wear from oversized sprockets and to improve sprocket protection. (d) The GP chain guide’s internal top- and bottom-raised Powerlip keeps the chain centered for efficiency and low drag. (e) With the previous design, the chain slap was loud and annoying. TM Designworks has reduced the noise by lowering the entry point and using a harder-plastic formula.
(2) Drag. You probably don’t think of a chain guide as a performance product, but you should. Anything that creates drag on the chain diminishes horsepower. In the case of most stock chain guides, which have an aluminum outer shell with a rubber slider, there is a significant amount of drag. TM Designworks’ “return memory” plastic formula nearly eliminates drag. How is this possible? Whereas the rubber in the stock guide grabs the chain, the hard plastic of TM Designworks’ chain guide allows the chain to slide over it.
(3) Durability. In stock trim, the Kawasaki KX450F and KX250F have the least durable chain guides on the market. The MXA wrecking crew wears through not only the rubber but also the metal in no time. It happens so fast that we don’t always catch how worn the stock guide has become. This could be dangerous. If you own a KX450F, you should order a TM Designworks chain guide before you leave the showroom floor.
(4) Installation. If you are replacing a worn-out stock chain guide, you should note that the chain tension will get tighter when you install a new chain guide. Installing the TM chain guide is simple—no need to break the chain. Plus, the chain guide has enough clearance to accept as many as three teeth on the rear sprocket. There is also a one-year, unconditional guarantee on all parts.
(5) Colors. TM Designworks’ GP rear chain guides come in black and green for the KX450F.
WHAT’S THE SQUAWK? No complaints.