[High On Octane]

Ummmm...  Well.....  This sucks.  The motor is out tho.  Kind of glad I'm not paying for parts at this point.

[mattsz]

Some previous owner must have thrashed that thing...

[High On Octane]

Some previous owner must have thrashed that thing...

Honestly could be.  I won't lie.  Haha  Honestly almost looks like oil starvation..  Oddly enough, the head gasket on the left cylinder, the composite had started breaking away on one corner (from poor fitting over the head studs), but the flame ring was still in tact.  So, it was sealing enough for compression, but was leaking oil badly into the cylinder.  So, left piston was completely opposite condition.  Right piston almost too clean, and left piston completely covered in burnt oil.

Does anyone remember the exact piston and rod combo I came up with a few years ago?  I just remember BSA A10 rods that needed the big end bored slightly.     Every time I price out forged pistons and rods thru HC's I about crap my pants.  Almost  $1K after shipping and conversion rates, or $250 per part, or $500 per cylinder.  Either way you slice it, big money.

I guess time to look into all my old posts here.  I wonder what the heck title that even is that made that topic under.

[Adrian II]

Just be grateful that the value of the pound has slumped since Brexit started...

A.

[High On Octane]

Pending weather, I should be splitting case halves today.  If it's super nice and not too muddy, I may take my buddy/co-worker's daughter out riding some trails today.  He got her a cool little mini bike for Christmas.  But, the track might be closed due to recent snow melt and be too muddy to open.

And speaking of dirt riding, I'm seriously considering making my YZ450F street legal with some dual sport tires and a 3.3 gallon "trail" tank.  As nasty as that bike is, I'm extremely confident it will do the ton with correct gearing.  As it is, it will stand the front wheel straight up just rolling a 1/3 throttle without slipping the clutch.  Even my buddy says it's the stupidest bike he's ever ridden.  I swear you could pull stumps with it.  Haha!

[High On Octane]

Hey guys!  Have an update!  I finally got the case halves split and getting ready to place a final order with Hitchcock's today.  Did make some interesting discoveries upon disassembly.  First was that the piston that was completely carbon/oil soaked actually had a broken scraper ring.  Which would explain why the bike wasn't smoking, but when the owner last started it, it was.  Could've have possibly stuck in the cylinder, as it hadn't run in a bit.

Also, I discovered the magneto drive chain was badly worn and way out of spec.  So, that could possibly explain why I've been having such a hard time getting the timing set correctly.  The timing chain itself was a little loose as well.  Luckily I have already ordered all new chains throughout, primary, magneto and timing.

After speaking with the owner the other day, we've decided we are going to do a complete full rebuild now, with forged rods and pistons.  Also, I will be completely rebuilding the heads with new guides, valves and springs, too.  I need to contact ARP as I want to replace the head studs as well, and these are not the original studs.  Anywho.  Here's some pics of the progress.

[High On Octane]

A few more pics.

[High On Octane]

Well, no dineros to go ride dirt bikes this weekend, and the boss is out of town for a snowmobile adventure.  So, the plan is to get as much prep work done as possible with the parts I currently have over the weekend.  With that being said, I'm going to try and get the trans rebuilt, new K70's installed, and rebuild the forks with the new springs I ordered years ago, but never installed because I wasn't sure how to go about spacing the fork springs.  Now that I've worked at a motorcycle shop for a year, I've realized that the spring spacers are nothing more than small sections of PVC pipe.

If I get all of that done in a timely matter, then I will start working on getting all the shiny aluminum bits polished up.  Anyone know any tricks for polishing the inner wheel hubs without unlacing the wheel?

[grumbern]

Well, I'm sure you wont like to hear this but: No way! If you want to do a propper polishing you need to unlace the wheels. As I too have struggled with polishing in the past, I'd like to recomend using "sanding stars" instead of sandpaper. These cost a little but they pay off! I have two sets of 180-240-400-600-800 grain and they are much quicker, less abrasive and give a better surface than sanding by hand. Plus, they last quite some time.

After you made the last sanding step (800), the number of steps obviously depending on the condition of the parts, let it sit for about 15-20h before polishing, to give it some time to build up a thin oxide layer. The polishing itself should be done with a fast running and strong disk, so you can create enough heat on the surface. This will "melt" it to a chrome like shine.

Don't use polishing fuids! These are just fine sanding agents but not polishing - they'll do the opposite and the surface is very prone of getting dull even faster. If not, it's just the wax of the so called polish that prevents it for some time. A good polish needs heat.

That's just some advise that I got from a guy who does this as a professional and I have to admit, on porous castings, as you might have on the bike, it's almost impossible to "seal" everything up to a state, where corrosion (dullness) doesn't get in.

Oh, if you throw out the old conrods - can I have them?
Good luck buffing up the beast!
Andreas

[grumbern]

Oh, just another thing, if you don't already know it:

http://recoainc.com/recoainc%20backup/twin%20oil%20mods.pdf

As you have the engine apart, that might be a good idea.
Greets,
Andreas

[High On Octane]

Thanks for the tips Andreas.  That's the first I've heard of not using some type of compound for polishing.  But, alas, there are several imperfections and deep scratches on the timing cover that I'd like to get smoothed out and cleaned up.  I also intend on going back to a normal primary cover, so will be polishing up that as well, along with the case halves.

As far as the case halves modifications, ERC has already provided me with those pages printed off a couple of years ago.  So, have already done a bit of research in that department.  I will be having the machine shop next door doing the O-ring mod for the rocker feeds.  I'll likely do the drilling myself.  And speaking of drilling and mods.  It sounds like they recommend blocking off the crank breather all together.  My original intents were fit a T fitting on the top/side of the oil tank, and run the original crank breather to the T, and then run the breather into the air filter like modern bikes.  Or, just put a breather element on the top of the T.  Any suggestions on that setup?

Sounding like I'll need to do a slight overbore on the cylinders too, as the forged I'm ordering pistons have a bigger expansion rate than the cast pistons.  And on those same lines, I'll probably have to have new valve seats cut too.  So, all said and done, the bike is going to have a brand new motor, head and trans.

[grumbern]

Well, I just sanded my primary case for the Chief today. I'll post some pics and you can check it out. I am always amazed how well this works, using the sanding stars. Don't want anything else!

As for the polishing itself, it is esential to let a thin oxide layer grow and then polish that within a given time with wax and a polishing disc, creating a good amount of heat. That will "close" the surface of the aluminium and make it resistant against weather. The polish you get from never dull and such, is basicly not a polish, but very fine sanding, leaving the surface smooth, but without any protection but maybe the wax/oil of the compound. The guy talked to took much longer to explain this and he/his company has done quite some research on that topic.

For the breather, I think by shutting off the crank breather they really mean the one in the crank shaft! This would blow into the primary creating a fair amount of preasure and cause it to leak. The breater on the crank case can stay and be connected to the oil tank. So your basic idea should work just fine!
On my bikes, I really like to let them "breath" onto the chain. That way they are always provided with enough lubricant.
Greets,
Andreas

[grumbern]

Ah, by the way: What I said only count's for aluminium. Other materials, such as stainless steel, brass, copper etc. can be polished right away and also with the use of these compounds. Aluminium is a little special

[High On Octane]

Remaining engine parts are being held ransom by FedEx customs.  They made me provide detailed information of every part in the box including what the parts are made of, along with its purpose, and a copy of my invoice, AND what the main bearings are made of and used.  A bit ridiculous if you ask me.  So, here I sit even longer without any progress being made.  It's always something with this Damn bike.  I guess that's what I get for naming it after a deceased Native American war chief.

[High On Octane]

Well, I have all parts lined up with the exception that one piston came without its ring set.  So those were shipped out yesterday.  Found out today a good Harley customer garage mechanic of mine is setup for crank balancing and is going to teach me to balance it myself.  So, that is exciting!  Hopefully will have the new valve guides installed before the end of the weekend, then heads are off to have new seats cut.  Going to try and get the case halves next door to have the O-Ring mod machined in.  Fun fun!