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Article 34

Major Gains in Engine Performance
By Jerry Matta

So you think we at SoCal XR's do nothing all day but play video games and shop on EBay.  Well, you'd be right. However, we actually got off our duff and did something.  I took my bike to Dave Miller the father of mini-bikes, along with the best tuner in the industry, and what we came up with, you can check out on the dyno chart.  We started with my 123cc motor, with a 69/68 Web cam, Stock valves, 200 carb, 50/50 gas, standard Miller pipe, with just a slight clean up on the ports. This is your basic modified motor, nothing real special, in fact it wasn't faster than anybody else's' XR, faster than TTR's , But not XR's.  Anyway, 59 dyno runs later, we managed to get my average motor well above average.  I can't tell you what we did, or even the numbers, but you can see for yourself the results.  Also, look how far it revved.  Yes, that's more than 14 grand and it will go more. 

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