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Old 09-15-2007, 02:50 PM
donzielke donzielke is offline
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Join Date: Nov 2006
Posts: 21
Default 1990 750 Sport - questions on custom carb setup

Hey gang, it's been a while.

I finally got the Sport running. Ended up taking it to HordPower here in Ohio. Runs pretty good I guess. That's part of my problem - I have nothing to compare it to... my Monster is a totally different beast (full DP exhaust, jet kit, K&N filter, otherwise stock airbox). I'm amazed at the difference a riding position can make (bent over vs upright).

JD Hord replaced the belts, checked the valves, new plugs, pulled the carbs and cleaned them, put new rubber carb boots on, adjusted the jets, and had it on the dyno. 61 HP and 46 lb-ft torque. He said that's not bad for carbs and slip-ons. He also put some foam pod air filters on the carbs. The problem, he said, is that the carbs are 38mm... WAY too big for the stock compression. He said this carb set is much better suited for a hi-comp piston setup. Well, I can't do that right now, so he got them set up the best he could.

The bike ran GREAT when I rode it home from Bucyrus to Columbus (about 71 miles). Rode it to work on the following Wedhesday and noticed a few things.

1. Brakes suck. Can pads go bad from lack of use? There is a strange feedback through the lever, not unlike the feeling of pads going over slotted rotors... it's not the same pulsation as a warped rotor, but I haven't checked them so that's not ruled out either. I'm going to the shop today to get some new EBC pads and new brake fluid. There's NO brakes if they get wet, as the last part of my ride home was in the rain and I had very little brake power.

2. Hesitation. The bike runs better at hard throttle applications. At steady highway running, it seems to be greatly affected when it's in "clean" air vs. "dirty" air (from heavy traffic or passing trucks). Is this normal for pod filters as compared to airboxes? Does hot air off the engine make it behave like this? I didn't notice this behavior on the ride home Saturday. The hesitation is very noticable and feels like a " I'm running out of gas" condition rather than a "I have no spark" condition.

3. Clutch drag. The clutch drags when the clutch is pulled and the bike is in gear (like at a stop light), and the bike is impossible to get into neutral when running. I don't know if the clutch fluid has ever been changed, I'm going to start with that. I've read a number of articles that stated the clutch slave is problematic and a new part was issued by Ducati. Any info on that? The previous owner put on these chrome H-D style fat grips and I'm wondering if it's not letting the clutch completely disengage... I'm planning on replacing those too.

Anyone with comments and advice, please let me know. Thanks in advance!!!

Here they are together:


A better shot of the Sport:

Thanks,
Don
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