ECTA/BONNEVILLE 200 MPH CLUB MEMBER INTRODUCES
NEW TURBO 250cc KAWASAKI AT SPEED WEEK 2006
By Bill Hoddinott
Jon Wennerberg and his photogenic wife Nancy, of northern Michigan, have become familiar figures at Bonneville and East Coast Timing Association in recent years as fast and serious motorcycle racers both! The couple has a potent ZX 12R sportbike which got Jon in the ECTA 2 Club in June 2003 with a 203.454 mph pass and the Bonneville 2 Club with a record of 207.065 mph at Speed Week 2003. Nancy has run this bike at 185+ mph at Speed Week. They have been featured on Speed Channel Salt Flats TV shows, and Jon serves nowadays as one of the MC Tech Inspectors at both Maxton and Bonneville.
Your scribe's interest was especially piqued this summer ('06) by news that Jon and Nancy had finished the conversion of their stock '96 Kawasaki 250 Ninja into a full-race turbo bike and had taken it to Speed Week '06 where it posted some very respectable new records! Both Nancy and Jon rode it, recording marks of 116.076 mph with fairing, and 113.987 mph without in classes 250 APS/BF and 250 A/BF respectively. They returned to Bonneville for World of Speed later, and on September 14, 2006, Nancy set an even higher record in 250 APS/BG at 120.289 mph.
This model is of special interest to the present writer because I have covered over 100K road miles on my own '88, which is identical to their stock '96 as it was, and also to the '07 models presently in the dealers' shops. This little gem has been a great success for Kawasaki and is still sold in large numbers after 21 years production. It lists for $3K new, cruises at 75 mph forever, top speed stock is 100, and it gives 70 mpg in road use. It is a comfortable 300 lb bike that handles like a road racer and is very, very safe with powerful brakes.
Far as I know, no-one has ever tried to apply a turbo to one of these before, so it wasn't too easy to find a shop that could take on the job. I talked to a couple of them and we worked on it a while, but never quite managed to get everything to a practical racing form.
But, we didn't give up. I knew we needed to use a Motec racing EFI computer for the turbo equipment. I asked Dave Dahlgren, who's the Motec vendor, for his recommendation for someone to do the engine building and turbo installation. Since the Motec system would have to interface with the rest of the bike we wanted someone that could work closely with him.
Dave recommended Mike Rich, of Mike Rich Motorsports in Pennsylvania, so we went to see him. He turned out to be just the right man to handle the job. Mike built everything as you see it, and he came out to Speed Week for a few days and helped us run the bike. I'll put you in touch with him and he'll tell you what-all he did to it.
We have Dunlop K591 V-rated tires on the original 16-inch wheels. These tires are the same sizes as the OEM tires, but a speed rating upgrade. And of course we have the regulation metal valve stems and caps in place.
Notwithstanding all this, once the turbo spools up and starts to put some pressure into the engine, the torque does jump up much stronger than stock. It peaks right around 10,000 rpm just like the stock engine does, and it pulls hard to the rev-limiter in all but fifth and top gear when the air load is building up. At Bonneville we can afford to wait for the limiter in fifth, even with the new "short-short" course, but at Maxton we re-geared one tooth bigger on the rear to get up to speed quicker. We ran nearly as fast there, even with the quicker gearing.
I think that's about everything I can tell you, so let me turn you over to Mike and he'll tell you all he did to the engine.