Does anyone know of any service bulletins on the 99 sportys dealing with top end lub or piston faliure.

Got a 99 in the shop with a real puzzle. 3rd top end with under 150 miles. identical piston faliure, rebuilt in two other shops. I really do not see an ovious reason why this motor went down twice!

wondering if there is anything out there about a factory defect from 99 to 02

thanks in advance
ron

What actually went on the top end.

front piston had chunk out at intake, rear piston had chunk out at exhaust, WIESCO pistons, second time. same location first time, under 150 miles

:rolleyes:

Don't know of any offhand. I've got just under 31,000 miles on my 99 883c, and all of the engine is OE and still going strong.

Where you using Wiesco pistons each time they failed or were you using OE pistons during one rebuild and wiesco during the next?

BTW,

Here is a archive of a site that has all the service bulletins

http://web.archive.org/web/20030629130203/http://harleyhog.co.uk/

what did the heads look like? that either sounds like a valve failure or your cam is positioned wrong, if you had your cams 1 & 4 switched which is easy to I know from experience, your valves will scrap your pistons. but that would be obvious. sounds more like a valve springs crapping out. did they check the tension on the valves?

"A chunk" Does this mean the valves hit? Or did the pistons melt and break? If you do a conversion and use flat tops with no chamber mods, you will have crazy compression, and maybe melt/ hammer with detonation..your pistons. If you have cams, you might need to clearance for the extra lift, or your timing might be off. I know one guy who put his own motor together twice and had the number one cam one tooth off. He broke two pistons, before bring it in. We found the cam timing issue when we took it apart.