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I wanted to share my interesting 250r engine build that i did. I took a stock 85 tri-pod (slang for 3-wheeler
) and reworked it with advice from more-torque. the engine is stock 85 model short rod stock stroke and the cylinder is non ported sitting at 67mm bore. i made a .050 plate to raise the cylinder this was to gain more favorable port timings. i modified the stock head so that the chamber would pilot into the top of the cylinder to gain back lost compression. i installed a 1-4 override transmission, v-3 reeds, cr 250r intake, cr stock ignition, and a 38mm mikuni TM. once i bolted the engine in my lonestar xulw all that was left was getting a pipe. i had an old fmf gold series pipe setting under one of my work tables. i ended up having to cut the spigot off the where it fits on the exhaust flange. i cut 1.5 inches off the the pipe and welded the spigot back on to fit this pipe in my chassis.
i took the bike to the track and with 11 paddle extremes 14-42 gears on an 8 over swingarm and 91 octane gas the bike run 5.2 - 5.3 at 56-57 mph!!!!
the digitron shows 1000 - 1100 temps with a max rpm i have seen is just over 10,000.
this turned out to be quite an amazing little engine!!!


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