Originally posted by Tirefryer
The only things I did to the bike performence wise was to replace the cans, rejet and reduce the size of the wastgate hole. They handle pretty well for a eary 80's bike. When not on boost these things are gutless dogs
I had the "power-up" kit installed on mine. It consisted of a plug in the right exhaust with a small hole in it. That allowed it to build more boost pressure. It also used a longer pressure tube that attached to the airbox. It was what triggered the wastegate and was originally plumbed to get pressure right at the turbo. Afterward, it waited until that pressure was in the airbox to open the wastegate.
I also redrilled the timing pickup plate and advanced it a few degrees. Then I had to run premium to keep the pinging to a minimum. Apparently the knock sensor couldn't retard it enough to overcome the amount of advance I introduced.
It did handle very nicely, but that turbo-lag and sudden rush of power could be disconcerting in tight corners. When I rode it over Trail Ridge Road in CO at 12,000 ft, it wouldn't start boosting until 8,000 or so. That was a real pain. I agree, launching it was a nightmare, but if you ever got a running jump on a literbike, he would have a VERY hard time catching up.
But my clutch wouldn't stay intact. I fried one, then put new discs and stronger springs in, and it still wouldn't hold. That's the drawback of the Seca Turbo--it used the same drivetrain as the regular Seca 650. That also limited top speed to 120 or so. It would've gone much faster if it had the gearing. It was also a very comfortable bike. Probably the first real nice sport-tourer.