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Ultimate Test: Team Losi LST

11/17/2004 by John Howell

Provider Name:  RC Car Action

Issue:  November 2004

Copyright:©2004 Air Age Media

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In this article...

Page 1: Intro
Page 2: KIT FEATURES
Page 3: SHOCKS & TRANNY
Page 4: PERFORMANCE
(continued from previous page)

SUPERSIZED SHOCKS
The first thing that catches your eye on the LST is the size of the massive blue-anodized shocks (shown here next to a standard, 1.10, stadium truck damper). When we spoke with Gil Losi Jr., he told us that it's considerably easier to make a larger shock work more efficiently and more effectively. During tests, the Losi engineers discovered that of all the shock/suspension-arm combinations they tried, the oversize shock was best able to handle the intense loads on the suspension that a 10- pound-plus vehicle will throw its way.

When you crack open one of these shocks, you find a large piston with an amazing 24 holes (instead of the two or three holes you'd see in a standard piston). In addition, the shocks have bleeder caps, long, 4mm-diameter shock shafts and dual O-ring seals. A locknut secures the shock piston to the shaft and, interestingly, the shock bodies can be filled from the top or the bottom. The big question is how much oil does it take to fill these suckers? According to Losi, you'll use approximately the same amount of fluid in 1 LST shock as you would to fill almost 3 standard shocks.


HIGH/LOW ON THE GO!

WHAT’S INSIDE
CLUTCH BELL/SPUR GEAR 18T/70T (1st gear);
25T/63T (2nd) TRANSMISSION RATIOS 13.8:1 (low); 6.91:1 (high)
FINAL DRIVE RATIOS
LOW 53.5:1 (1st)/34.78:1 (2nd)
HIGH 26.8:1 (1st)/17.41:1 (2nd)

Team Losi uses only highgrade, CNC-machined gears in its transmissions. This cutaway shows the high/low user-selectable gearing options.

One of Team Losi’s original goals with the LST was to design a transmission that would allow drivers to rock-crawl in a very low gear and then be able to switch to a higher gear when it was time to hit the racetrack. It also had to be compact and bulletproof. Generally speaking, transmissions with all these features have a history of causing designers plenty of headaches. The view shown here gives you a clear look inside the tranny case. To switch from the superlow gearing to the higher gear, just turn the “Hi/Low Mechanism” knob at the top of the tranny. Once switched, the 2-speed transmission is either engaged in a superlow final gear (53.5:1 in first gear, 34.78:1 in second) or high gear (26.8:1/17.41:1). During our tests, we heard a little spur-gear/clutch-bell clatter, but that is to be expected. Not once did the tranny glitch on us; so far, it seems very solid.



DIRT-READY DRIVETRAIN

The LST’s drivetrain is so unique that we have to look at each component separately. It’s built from the ground up for monster abuse. See for yourself.

HIGH/LOW GEAR SELECTABLE TRANNY. The tranny is a highly engineered unit with a high- and lowrange gear set. The transmission uses a combination of machined-steel and hard-anodized-aluminum gears—no plastic gears. Everything down to the shifting forks is made of heavy-duty materials. The lowrange gears give the truck the ability to easily climb and crawl over obstacles; it’s truly impressive to see this beast rock-crawl. The high-range gears get the truck moving at a good clip, but there isn’t any sacrifice when it comes to low-end snap. Even in high gear, the truck still wheelies off the line. The only bummer is that the high/low settings cannot be accessed on the fly via the radio. To select high and low, you must turn the selector knob on the tranny. It’s easy; but you do have to stop the truck and lift the body to the side to access the knob.

A clutch-type 2-speed is mated to a unique, adjustable high/low transmission. To switch between high and low, simply turn the shifting knob on top of the transmission.

RADIO-OPERATED REVERSE GEAR. It’s amazing that Losi was able to engineer a reverse system into such a compact transmission design. A separate servo and your radio’s third channel operate reverse on a constant-engagement tranny. Simply wait until the truck has fully stopped, flip the third-channel switch on the radio and back up. The transition from forward to reverse is very smooth; we didn’t notice any clunky action.

CLUTCH-TYPE 2-SPEED. A standard-issue, clutchtype 2-speed sits at the end of the transmission shaft, and it’s easy to get to after you’ve removed its protective shroud. It’s adjusted just like any average 2-speed: two setscrews allow you to adjust the shift point. The back of the assembly is exposed, so if you run in really loose dirt with a ton of small rocks, keep an eye on the plastic spur gears. Team Losi has recognized the potential for dirt to get into the works and will soon offer a protective rear cover.

ADJUSTABLE SLIPPER CLUTCH. A big truck like this needs a beefy slipper, and the LST doesn’t disappoint. A combination of three pads and two discs rests inside a very compact slipper cage. With three pads instead of only one (or even two), the slipper can better absorb punishment and keep going. Removing a rubber plug on the outside of the 2-speed shroud gives you quick access to the slipper-clutch nut.

SEALED DIFFERENTIALS. The LST comes with sealed bevel-gear differentials in the front and rear. The gears are heavy-duty, CNC-machined steel; you won’t find cast-pot metal gears in this truck’s drivetrain. The diffs come packed with grease from the factory. That is fine for bashing around, but if you plan to race the truck, you can fine-tune them with heavier or lighter silicone fluid.

REBUILDABLE DRIVESHAFTS. Heavy-duty, chromeplated, rebuildable universal driveshafts connect the tranny to the front and rear bevel-gear diffs. Similar units are used between the diffs and wheels. DUAL-DISC BRAKE. Mounted on the front of the tranny, a dual-disc brake unit with drilled steel rotors and padded steel calipers provides ridiculous braking power. There’s nothing especially new about the brake’s construction; Losi just got it right! The truck stops on a dime.

RUBBER-SEALED BALL BEARINGS. Monster trucks live in the dirt, which tends to eat bearings. All monsters should have rubber-sealed bearings because they are the only type that is truly sealed.

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