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This week was a busy one with the upcoming CMRA season opener next weekend and a mini/motard trackday at NOLA. I got Kevin Bradford and Zachariah James KX 65s ready for the weekends. This year we are bringing up Zach to the 65. He got third last year in Jr. Motard in the CMRA on a KLX 110, we consider him first in a way due to his bike being built for the word and spirit of the rules. K.B. rode to a first in the F-6 class in CMRA due to a bit of class attrition at the end but he had a few inspire rides through the large pack of Groms prove he is a player in the kids mini race world. Last year in December we seized the Wiseco single ring piston at the long NOLA straight away at the WERA race. I blamed hours of the set up, a temperature drop and most likely insufficient warm up. I got a rebuilt cylinder, a new wiseco put it together and it seized on half a lap. A discouraged K.B. really wants a 4 stroke for the next one but by working with Dean and Ed at Millennium we had the exhaust bridge welded modified the head for less compression and set the bore size slightly large to allow for the extra heat of an extra long straight. The cylinder is not ported and fired up and ran great right out of the box using a 200 main jet and 32:1 ratio Motul and real 89 octane gas.
Zach's bike is a 2009 KX65 that we got a few weeks ago. I bough it sight unseen on Craigslist for 1050$ and soon realized the rebuild was a bad deal. Previous owner said he had it re ringed and it did fire right up so it was what it was. Zach spent about 6 sessions learning how to ride it before it seemed to seize and making noises form the lower end of the engine. I did a top end rebuild, had the cylinder replated loose, bought a new head, piston and related top end parts from Kawasaki. (thanks for the help GN Gonzales) and it too started right up. It also still made a bad noise however and I pulled it apart quickly discovering that some parts like the transmission looked bran new but the bearings on the sides of the crank were slightly blue and that the crank had been rebuilt using the some other previously overheated crank parts. Also the bearings were only changed in one half of the cases shown by the ones on the left side being chinese bearings and the right being proper Japanese. Big thumbs up to wiseco and HotRods for putting together a transmission bearing set. If they would include the waterpump bearing my Hotrods/Vertex bottom end rebuild kit would have been complete. I put it together and went too big on the main for run in and settled back on a 190 and will fool with the needle later. I built it with the extra base gasket to reduce compression. A less expensive route that the mods to Kevins bike. It fired right and unfortunately picked up a flat preventing its use for the day. Zack used Kevs bike and built up some confidence for next weekend. We will be working on body position, a lot. I had planned to put up a video but due to the aforementioned flat couldn't. Video can be a great way to show someone how different their body position actually is verses what they think it is.
We got to the GAMRA track day as the crowd dispersed and got in the test and tune cycle with the go carts. One of those guys had a "Duper"? cart. It has a neat Wankel Rotary engine and makes 55hp. Zach put in the laps and here we are. Later.
 
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