Yet another learning experience

posted Sep 12, 2011, 5:33 PM by Scoob Edoo
Yesterday was another Hypermoto event at NJMP and again (still) the clone motor wasn't working.  No matter what we tried with two different carbs, it wouldn't start.  We set up his other kart for Junior Sportsman and he ran that with the Hypermoto Advanced group again.  This time we tried a few changes to help loosen up the kart and get more revs out of the motor.  Mission accomplished on both fronts: narrowed the front track by about 1.25" per side and pumped up the rear tires 3 psi more than the fronts and the kart was handling perfectly; and I opened up the carb slightly and it was revving over 14k rpm on the stand!  On-track he looked like a star and he demanded that I not touch anything.  That worked well for the two morning practice sessions, while the weather was cool and 90+% humidity.

Unfortunately, the weather changed somewhat and I did not recognize how much it had changed.  The carb was tuned OK, but in the pm conditions he started to see a problem at the end of the front straight.  The motor was falling on its face after the long 13+k rpm run down the straight.  When he let off to set up for turn one, it was actually stalling.  And because he couldn't tell me what happened after the first time, I didn't get that the high jet was causing the problem.  What I think would have worked pretty well in those conditions was upping the high to maybe 1/4 turn out to see how that affected the drop of the high rpms.  Next time.

The day was not a total loss, though.  Kieran rode his bike down to watch some of the other classes at Turn 1.  He finally saw how the faster classes were taking the corner and he followed their example and went a lot faster as a result.  He was very happy to have learned it himself and put it into practice.

And toward the end of the day, Jack brought another carb for us to put on and, BAM!, the clone motor started right up and I even adjusted it to idle pretty well.  Now we have two working karts and I'm a happy camper/team owner.  Unfortunately, we now have 4 weeks off since I'm going to Germany at the end of the month and we miss a Philly event.  Next up is the last Hypermoto race on 9 October.  Hopefully I'll get to run my shifter at that event, too, since I'll be able to install the wide bumper from his autocross kart onto my kart (or maybe I'll just buy one for my kart separately so we'll be set).