Last year my uncle & I bought a '90 750 Sport as a fixer-upper and it's finally running again.
Sparing you all the gorey details, here's my dilemma. The bike has had the stock Weber and airbox tossed in exchange for a set of 38mm carbs from a later model 900ss. It has long intake runners, and the carbs are connected. The carb mouths are just a few mm from the battery. It has Cobra F1 slip-ons. Anyhow, I had the bike worked on recently - new belts, valves checked, new plugs, carbs torn down and cleaned throroughly, jetting adjusted, and installed foam pod filters on the carbs.
My mechanic's first comment is these carbs are way too big. He said they'll be perfect if we do a high compression piston kit down the road, but right now they are overkill and were extremely hard to tune (4 hours on the dyno getting it right). He still isn't happy with the performance. But the bike runs really good compared to before. He measuerd 61 hp and 46 lb-ft torque at the rear wheel.
The shop is about an hour's ride from my home, and I rode it home with no problems - ran flawlessly. But the more I ride it, the more I feel a hesitation from time to time. Kind of feels like a fuel starvation situation - not a misfire or lack of spark situation. It happens at steady throttle, usually above 45 or so MPH, and usually when it's in traffic. Not sure if it's temperature related or not yet (it's been pretty hot here, around 85 to 90 degrees F). Definitely more noticable in traffic than running alone on the road.
My question is... is this normal for an open-pod setup? Every other bike I've ever owned has had an airbox/pipe/jetkit so I don't have anything to compare it to.
Here's a pic. Still needs to get the Harley grips taken off, install the new tires, install new brakes pads, get some stainless steel braided front lines, and install bar-end mirrors. Then we're going to ride the wheels off it.
