Member Photos

[Edwardo Piet]

But I have no clue what a freaking magneto even is.

[TheRocketSurgeon]

But I have no clue what a freaking magneto even is.

Magnetos are a type of generator, formerly found in bikes/cars and still found in aircraft, which produces pulsed DC power to the sparkplugs. Modern cars/bikes use an Alternator (which produces AC pulses like a sine wave), of which the "minus" pulses are clipped out by a Regulator. It's more efficient in terms of stepping up the voltage to produce the current which leaps across the plug gap, but it adds a layer of electrical complexity that can fail (the regulator, thyristor switches, etc), which is why aircraft still use the older, less-efficient setup. Still gets the job done, and is safer-- if your bike engine fails, you just pull over to the side of the road, whereas a plane may be in Big Trouble™ if the engine conks over something electronic.

If you look at very old motorcycles, like the Harley Davidson "Knucklehead", you can still see the magneto setup. Cars, I know less-well.

[Joods]

Judi, didn't you show that photo about a year ago?

I may have. I did this work back in 2012. It's just nice to re-live a memory.

[Joods]

CD was more specific, but you are both correct.

YES!!  I dismantled a blown engine from a 1987 Jeep Grand Cherokee. Tore apart the head, removed all the rocker arms and took it down to nothing. Cleaned it up, replaced all the parts, put in new head gasket, valve cover gasket, thermometer, spark plugs, wires, dist. cap, rotor, gave it oil and did all the rest of the tedious work and there you are. Took me 11 hours stretched out over two days. I did have help from a friend, but this was a project I wanted to do mostly by myself.

I like your spring compressor! Mine's a clunky POS; I've been looking for a better design.

Did you polish the heads while you had 'em off?

We rented that compressor but it was really nice to have. I also had to buy a torque wrench. Let me say, those are nice, but if you don't get the numbers exact, everything goes to shit. 

The heads weren't polished, but they were cleaned meticulously to the point where one could probably eat off of them. Rubbing alcohol, q-tips and cotton balls are awesome.

[TheRocketSurgeon]

I like your spring compressor! Mine's a clunky POS; I've been looking for a better design.

Did you polish the heads while you had 'em off?

We rented that compressor but it was really nice to have. I also had to buy a torque wrench. Let me say, those are nice, but if you don't get the numbers exact, everything goes to shit. 

The heads weren't polished, but they were cleaned meticulously to the point where one could probably eat off of them. Rubbing alcohol, q-tips and cotton balls are awesome.

I asked because I spend a LOT of time with bike heads; porting-and-polishing is one of my specialty upgrades for my customers. It's relatively simple (I use that term loosely), once you know what you're doing, but it improves the breathing of the engine considerably for very little cost. Engines are basically air-pumps, in terms of how they operate, so improving its ability to breathe-- that's why K&N filters and freer-flowing exhausts do so much for your power-- is everything, unless you wish to start punching out cylinders for more displacement. It's rarely even necessary to re-jet the carburetors, since the change is simply how efficiently the fuel-air mix moves from the carbs to the combustion chamber, not actually changing the volume of either. Changing the pipes or the filter, however, changes the total air-flow volume, and thus requires adjustment of the fuel mix unless you have a modern fuel injection system that automatically compensates (I don't think your Cherokee would have that).

[Aroura]

Went to a Pioneer themed holiday party yesterday at a local museum/historical house.  So much fun!  Got to ride in a horse drawn carriage afterwards in our little local parade.  No good pics of that, sadly.





Sadly, there is never anyone to take pictures of me, so you guys will just keep getting pics of my kid.

[Joods]

We rented that compressor but it was really nice to have. I also had to buy a torque wrench. Let me say, those are nice, but if you don't get the numbers exact, everything goes to shit. 

The heads weren't polished, but they were cleaned meticulously to the point where one could probably eat off of them. Rubbing alcohol, q-tips and cotton balls are awesome.

I asked because I spend a LOT of time with bike heads; porting-and-polishing is one of my specialty upgrades for my customers. It's relatively simple (I use that term loosely), once you know what you're doing, but it improves the breathing of the engine considerably for very little cost. Engines are basically air-pumps, in terms of how they operate, so improving its ability to breathe-- that's why K&N filters and freer-flowing exhausts do so much for your power-- is everything, unless you wish to start punching out cylinders for more displacement. It's rarely even necessary to re-jet the carburetors, since the change is simply how efficiently the fuel-air mix moves from the carbs to the combustion chamber, not actually changing the volume of either. Changing the pipes or the filter, however, changes the total air-flow volume, and thus requires adjustment of the fuel mix unless you have a modern fuel injection system that automatically compensates (I don't think your Cherokee would have that).

I know nothing of how to work on bikes so I'll ask, are bike heads visible from the outside? Since there's no "under the hood" parts, I know, logically, that there are internal parts. The Cherokee belonged to a friend of mine. 

On a side note, when I was 19 (25 years ago), I rebuilt a double barrel carbureator.

[brewer]

Sneak attack from the rear.


Poor corgi never had a chance.

[Longhorn]

Ghhhhhh.....puppehs!!

Nobody stands a chance against this much adorable charging at full speed

[TheRocketSurgeon]

I know nothing of how to work on bikes so I'll ask, are bike heads visible from the outside? Since there's no "under the hood" parts, I know, logically, that there are internal parts. The Cherokee belonged to a friend of mine. 

On a side note, when I was 19 (25 years ago), I rebuilt a double barrel carbureator.

Depends on the bike. On a bike with a side-fairing (such as a sportbike/racebike), you won't see much of the engine other than perhaps part of the clutch and gearbox assembly. On many bikes, the whole engine is visible. Still, with very few exceptions, you need to remove the engine from the frame if you're going to be taking the engine apart at all. 

In bikes where the heads protrude from the bike, such as the Honda Gold Wing (GL1000/1100/1200/1500/1800) designs and the BMW R-series boxers, you can remove the heads quite easily. See below:

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Edit to Add: This guy took the whole cylinder off; you can see the connecting rod sticking out the side of the engine, and the rocker cover on the ground. The head itself is not in sight.