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Hi there

A friend of mine wanted to get shot of his 2001 750 Sport i.e that he hadn't used for about 7 or 8 years.
It has the Ducati Performance Remus cans on it, but I do not know if the ecu has been changed (although I suspect not)

I bought the bike and decided to try and use it.
I started by servicing it (fuel filter, renewal fuel, new plugs, new timing belts, check valve clearances, etc)

When I initially started it up, I noticed that the front cylinder gets hot much faster than the rear.
After a quick look online I realised there might be an induction leak somewhere, so I took off the airbox and tried to see if there were any obvious leaks, and looked a bit at the seals around the throttle bodies

At that point, I noticed that there was some blackened oil residue around the throttle body of the front cylinder.

I cleaned it up and put it back together then took it for a ride around the block, with the following observations:

The bike doesn't really idle without the choke, and the idle is less reliable the hotter the engine gets.
The power is not very good and drops to virtually zero as the engine gets hotter.

I've been looking around a bit and I am starting to wonder if the front cylinder might be partially seized?
Compression on both cylinders is within spec (just)

Any ideas what the problem might be?

Thanks for any help.

David

Also, I have attached a photo of the spark plug from the front cylinder, the spark plug was completely new, this is what it looks like after about 10mins of riding

986276
 

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Did you check the fuel injectors for a good spray pattern? I sounds like from your description and from the photo above it's running lean, with plugged injectors or induction leaks. Check again carefully for something loose or missing on the throttle bodies, especially below the butterflies where vacuum is high. Above the butterflies or in the airbox doesn't really matter here. With good compression, that cylinder is probably ok. -Gordo
 

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What does the rear plug look like. If the front is running and the rear isn’t, the front will definitely get hot quicker . Try some injection cleaner. Check for spark.
 

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Check the injector signal at the injector wiring with a noid light--if you have a good signal then pull the injector & look at the spray pattern these are the first things I would do
 

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what is the compression ? detailed info helps greatly --did you check the compression with the throttle body's still attached to the intakes? or did you remove them? --did you have the throttle wide open when checking compression if the throttle bodys were still attached? these things do matter
 

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also another thing to check --do a fuel pressure test and see what numbers you get there
 

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Just fixed this problem on my 900.After standing for ages there was a lot of yellow residue all through the fuel system.New pump,new filter,check all pipes(the ones in the tank were breaking down,removed and cleaned injectors like this...
And finally,what I think was the real problem,remove the pressure regulator,in the back is a circlip,take that out,pull it apart and you will find a fine filter and a ring of holes.Clean out with carb cleaner.Mine was blocked,now starts and runs freely on the button.
 

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I had a very similar issue tuning a 03 800SS in 2015 with 1106 miles on it. I cleaned the injectors and it got better but later took them to a speed shop by me “Marren Injectors”, who did an unbelievable job with them. They clean, map and chart spray patterns and provide you with all the info for them. I actually had slight pitting on the horizontal injector and they suggested I run that in the vertical (hotter) cylinder for extra cooling. Bike has been fantastic since. Over 10,000 miles now and countless track days and she runs with the best of them. Good luck.
 
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