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By Derik Martin We all know the drawbacks of the 1976 CR250M Elsinore, suspension suspension suspension! Having raced one of these bikes back "in the day" I had a certain sentimental attachment to the 1976 and that ís why I opted to try to modify this bike rather than purchase and race the ever so popular 1978-1980 CR250. Contrary to most peopleís belief the motor and turning ability on the 1976 was very competitive for its day. Prior to starting this project I read several old dirt bike tests, which confirmed my opinion of this bike, which was all it needed, was a decent suspension. Here are the modifications I have made to make this bike as smooth riding as the Huskyís, Suzukiís, and Yamahaís of that vintage.  Front Forks: The front forks on the 76 are very limited with only 7 inches of travel. I took the stock forks off and put on 1979 Honda CR 250 forks. This is not as simple as it sounds for to do this modification you will also need to change the triple tree to the 78-80 and get a bearing kit to make the triple tree fit the 76 frame. You will also need a 78-80 front hub and brake. The later model 78-80 front forks are 36 inches the stock 76 forks are 30 inches. To make the bike sit level and eligible for AHRMA for itís class you need to cut the internals of the forks to yield nine inches of travel. I cut two inches off of the springs and two inches off the damper rod. This gave me a very good spring rate for my 180 pounds but will vary on your weight and ability. Since the 79 fork springs are under sprung increasing the spring rate helps these forks. This modification can be altered depending on what length rear shock you are going to use and how much travel you want. The 79 are listed as having close to 12 inches of travel but have closer to 11. You will also have to experiment with preload since this modification make the bike settle about 3 inches when you put weight on it. Too much preload and the dampers bottom at the top of their stroke and too little and the bike settles too much. I am still experimenting with this aspect of the modifications but it looks like ‡ inch is the magic number, or you can simply add a little air. Rear Suspension: I donít believe laying down the shocks is the way to go with the 1976; the frame of this bike wasnít geometrically designed that way. If you look at the Bultaco's and Montesa's of this vintage they managed plenty of plush travel leaving the shock straight up and down. I consulted with Sandy at Work Performance on shocks, we decided that a triple rate spring would be the way to go, the shock I selected had 5.5 inches of travel and with the forward mounting of the 76 Elsinore that translated to 9 inches at the rear wheel. The shock length eye to eye was 16.25 inches. With a little math and mock up I determined that this would make the bike sit exactly level from front to rear. Test Ride: These modifications turns the 1976 CR250M into a completely different animal. It turns as good as it did stock since the wheelbase was kept the same as before the modifications. The suspension is evenly balanced and there are no surprises itís predictable and tracts straight. The only thing you will notice is that now you can go so much faster on the track that maybe some motor modifications are in order? This bike is a step above the competition, now only if I were a better rider! |
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