Documenting life during the first attempt at restoring a vintage motorcycle.

Similar to the zen -like feeling that is realized through surfing,
motorcycle repair can elevate the mind to a meditative state that eludes time and space...
Meaning I obsess over it, get frustrated, yell, laugh at myself and overall waste a lot of time.


Pieces of the Pie: Piston Pete & The Pissed Off Pirates

I admit it has been a while since I've worked on the motorcycle. I haven't had very many visitors to this site and my childish humor and inclination to use alliteration has resulted in this title post. Simply hoping to lure any would-be visitor to read my rant about replacing the Piston Head on the motorcycle a little longer than the 2.5 minute average time spent visiting my blog. Hope you weren't to excited about hearing a strange escapade involving a deranged motorhead named Piston Pete and a gang of agitated privateers. Sorry, no story here. I actually just now Googled "Pissed Off Pirates" to see if an entity even existed by that name (i.e. musical group, pirate workers union, angry eye-patch wearing enthusiasts, etc...) and found this website dedicated to a Biker Club in Seattle: Pissed Off Pirates and takes you to a gay motorcyclists dating site. Another search of "Piston Pete" only came up with a chain of gas stations and their adorable logo of a cartoon piston named Pete. Anyways, wow that was boring and I apologize. IF you have made it this far, keep reading a little longer and find out about the next step of progress in the motorcycle rebuild.
I removed the cylinder head, which was surprisingly easy, 4 nuts and it separated from the bottom piece. Took a peak inside and saw the blackened charred top of the piston (not good, see picture above). After a little prying, pulling and gentle hammering with a rubber mallet, I was able to remove the cylinder base. Was I surprised when a piece of the top piston ring fell out? No, no I was not. I now know better than to hope for the best. In fact I had assumed anything from a beer bottle to a litter of puppies would be jammed inside the various orifices of the engine. So what does that mean? Well the piece of the piston ring (please see above picture, again) was stuck inside the cylinder aka combustion chamber, while the motor was still being used/running for who knows how long, subsequently scratching the hell out of the cylinder walls that should be oh-so-clean and shiny. The reason being is that a smooth cylinder wall is essential to create a good seal in the combustion chamber with the piston and piston rings during the ignition/combustion cycle. This is the key to good pressure which means power out of the motor, proper timing and an overall smooth running motorcycle. Unfortunately it is scratched pretty bad and slightly rusted from having gas sitting in it. The previous owner(s) also had been pre-mixing oil into the gasoline instead of using the oil injection system built into the bike (which we will visit in the near future) and caused a lot of carbon build up inside the cylinder and on the piston head (see pictures above one last time). Based on the condition of everything else on the bike, I assume the previous owner(s) also failed to use the proper ratio when mixing the oil so the cylinder and piston where improperly lubricated which may have been one of the causes of the broken piston ring. Don't worry my friends, I will be honing out the cylinder to get an almost smooth surface and replacing the piston head and rings with brand new ones. A little tricky to measure the inside of the cylinder walls to know exactly which size piston to get (they come in all sizes by very small increments), but with a little luck and mostly just using the right tools (micrometer), I'll be moving up in size by just a few tenths of a millimeter. So the next step will be cleaning the years of grime, dirt and oil off the outside of the cylinder base, shining up the inside of the cylinder walls and sizing up the new piston head. Later I'll tackle the oil pump and oil injection system.
PS - still can't remove the flywheel from the magneto. I may have to visit a shop, lame.

Font size

No comments: