Mystery part in crank

If you need technical information or help with your BOSCH ignition squarecase Ducati 900SS - Darmah engine - post your FAQs, comments & questions here.
Post Reply
User avatar
AndyCapp
Mariana
Posts: 29
Joined: Fri Jun 10, 2011 11:30 pm

Mystery part in crank

Post by AndyCapp »

Crank_MysteryPart.jpg
My big end has expired after only 8000 miles. On removal of the two plugs from the crank web I found this wedged in the middle. Ok, this explains my cranks early demise, but what is this part and where did it come from? It appears to be spring metal.
Uncle Steve
Cucciolo - the Lil Pup
Posts: 5
Joined: Mon Aug 01, 2016 10:49 pm

Re: Mystery part in crank

Post by Uncle Steve »

The only thing I can think of that looks remotely like that is part of the gear selector fork. Regards Steve
User avatar
AndyCapp
Mariana
Posts: 29
Joined: Fri Jun 10, 2011 11:30 pm

Re: Mystery part in crank

Post by AndyCapp »

On thinking about it more, I came to the conclusion it's far too large to have found its way there from somewhere else, so must originate from there.
If this was placed directly in the middle, it would direct the oil flow around it - towards each plug. Without this, the oil would simply flow straight past. So I guess its important to have it in place. As mine is broken, any ideas where I get a new one from ?
wdietz186
Cagiva Alazzura
Posts: 707
Joined: Sun Sep 10, 2006 5:40 pm

Re: Mystery part in crank

Post by wdietz186 »

Some cranks had a restrictor in the feed end to boost the feed to the top end. It was a roll pin [spring steel] that fit a few millimeters in from the end. Leave it out and read the article Kevin Bracken wrote about building his race engine[s] and improving the oiling system.
Post Reply

Return to “Squarecase BOSCH Ignition Engines > SD, SSD Darmah, late 900 SS & 900 GTS”