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The RL250 Parts Manual lists only one rear shock part number for all production RL250s. The sales brochure for the 1974 RL250L shows a rear shock with a single progressive wound spring, though, while the 1975 RL250M sales brochure shows the dual spring setup. I, personally, have no confidence that the RL250 was produced with anything but the dual spring shock. I have seen RL250s with a single progressive spring Suzuki shock but these shocks could have come from any number of production bikes. And, to be fair, there are about 30 inconsistencies from the production RL250 in the 1974 sales brochure photo.

The distance between mounting hole centers is about 300mm or 11 7/8". The spring configuration is two springs of unequal length separated by a plastic slider. The white plastic slider keeps the springs centered relative to one another and centered on the shock body. There is a five position tension adjustment on the bottom of the spring pack. With the tension adjuster at the lowest setting and the spring pack measures about 9" in length. The longest spring measures about 6" and the short spring about 3".  

The two springs are of the same diameter wire and the coils are spaced the same distance apart. The only difference is length. So, the two-spring unequal-length configuration creates a kind of 'progressive' setup. The longer spring rate is about half the rate of the shorter spring.

The original RL250 rear shocks were never anything to write home about. I place them in with the group of modifications that the factory would have eventually corrected given the opportunity. But, again, with only the two years under their belts, few engineering improvements were incorporated.

An RL250 restoration will need to have a pair of the original rear shocks to be correct. Unfortunately, nearly all of the existing shocks are in pretty bad shape overall. The chrome on the springs can get pretty banged up, the shock body itself can show a lot of wear, the rubber bumper is dry and cracked, and the plastic slider between the springs that used to be white is now yellow and cracked. On the plus side, they don't leak because most, or all, the fluid leaked out years ago.

In the world of restoration sometimes you have to fudge a bit to achieve your goals. What this means is that you have to make your worn out shocks look as close to new as possible. If your restored RL250 is going to just sit in the den, store window, or in a museum, it won't matter that the rear shocks don't really work.

Disassembly of the shock is not difficult.

bulletThe top shock mount is an aluminum casting that is threaded onto the shock inner shaft then drilled and pinned. Drive the roll pin out but don't try to unscrew the top mount yet.
bulletRelease the spring tension. The springs are preloaded and held in place by a steel disk at the top of the spring pack. The spring must be manually compressed enough to allow the disk to be slid off the top of the spring and out from under the top shock mount. The easiest way to accomplish this is with a helper compressing the spring.
bulletUnscrew the top shock mount.
bulletAs a rule of thumb, keep the top mounts together with the shocks they came from.

An alternative to the above disassembly process is to just remove the disk at the top of the shock. This will allow the long spring to be removed. The slider's inside diameter will not allow it to pass over the still installed top mount so the slider, the short spring, and the adjuster sleeve cannot be removed all the way. This shortened process may allow you enough room to clean and polish, though, without removing the top mount.

Once disassembly is accomplished, everything gets a good cleaning and the springs can be rechromed. The shock body can be polished somewhat but it is not likely all the scratches can be removed. The shock itself is not made to be disassembled and rebuilt.

Here is where we would talk about the justifiably dreaded hydrogen embrittlement of the springs during the plating process and the need to dehydrogenize by baking the springs after plating at 400 degrees or so for a couple of hours or whatever parameters your plater thinks is reasonable. I suppose that you can think of the springs as decoration and not go through the baking process but that will have to be your decision. Your decision is permanent, though. If too much time passes after plating, the springs cannot be dehydrongenized and baking will only make your now brittle springs hot. Your plater might even have a requirement that the springs be dehydrogenized.

Reassembly is just the reverse of the above except that you should install the Matrix Motor Sport reproduction Spring Slider to finish off your hard work.

Click on the thumbnails to enlarge image.

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Last modified: 05/26/14