Slides and ramps.

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Ray O'Donohue
Parallel Twin
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Joined: Tue Oct 13, 2009 8:11 am

Re: Slides and ramps.

Post by Ray O'Donohue »

You may have a subtle chalky deposit on the slide bore which is VERY hard to see unless angled into a good light "just so". On vacuum operated slides,this can cause havoc,and is removed with a mild polish-not with carb or gum cleaner spray. Hard to imagine how this could cause a problem with a conventional slide such as you are working with,but it is worth a look.

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Joined: Thu Nov 10, 2011 4:56 pm

Re: Slides and ramps.

Post by herbg »

Thanks for your suggestions. I should have mentioned that the carbs were "restored" -- cleaned up with new gaskets, etc.
Looks like I will have to remove the carb(s) from the bike to have a closer look as there's something odd going on.

I know the cables aren't helping as I can't seem to get enough slack in the rear carb unless the locknut is removed. Since the cables are original, I may have to spring for new ones.

2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

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750 GT
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Re: Slides and ramps.

Post by geodoc »

This may not apply directly to your problem, but just to add to the info-hopper. I had a slide sticking problem with some PHM Dellortos on a Guzzi special. Tore my hair out trying to figure out the problem. It was only one side that was sticking and would prevent the slide from bottoming. Turned out to be gum deposits from a fiberglass tank made with non-ethanol compatible resin and the dissolved resin in the fuel was causing the sticking.

The only one slide sticking threw me off - still don't understand that one. Lined the tank w/ POR-15 after cleaning the carbs and - fixed.

Do you have some sort of old ethanol soluble tank liner in there? ( I assume you have a steel tank)


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