[kayyak]

Thanks M&S, the routing really worked and the oil leak has stopped!

But as I see the notes from Bunn, his kit seems to be very impressive, running on cleaner oil and no recycling of unwanted stuff back into the tank. My Thunderbird 350 LB (Electra-x engine) is throwing a lot of oil into the catch can, so I prefer not leaving it on the chain but send good stuff back.

What are your thoughts?

[mbevo1]

Well, I have the iron-lung, so I'm not familiar with the LB characteristics...  as far as the Bunn goes, I guess most folks hate it or love it.  Seems like an expensive solution to me.  If you have a lot of oil being blown out, you might try extending the line out of the crankcase straight up to the top frame tube before you loop it anywhere.  You can extend that line back to the rear fender if your worried about oil being blown on the chain/tire. 

Ace uses this method and describes it here:
"Here's what to do.
Get some new breather hose at the hardware store. About 6 feet of it, and you can cut off any excess when you're done.
Something like 3/8" inside diameter flexible hose is good. I use the clear vinyl tubing that I got at Lowe's, so I can see what's going on in the breather hose.

Anyway, re-route the new breather hose, so that it curves up high, right at the beginning, where it comes out of the engine connection. Don't kink the hose trying to get it to turn quickly, just curve it upwards to go over the frame under the front ot the seat. Nice and high.

Then lead the hose along the fender brace toward the back of the bike. Use nylon cable ties to hold it to the fender brace. This makes it look nice.

End the hose at the bottom of the tail end of the rear fender.
Put the duckbill on the end, in a way that looks pretty good.
You can trim and fit the way it looks good to you.

End result:
The initial high routing of the breather hose acts like a "stand-pipe", so that any oil that makes it into the breather can run back down into the engine.
The routing of the hose along the fender brace makes the hose almost invisible when installed, keeps the hose up high until the tail end of the bike, and looks good.
The duckbill on the end at the back of the fender will work just as good there as anywhere else in the line. If any oil does make it out the back end of the breather tube, it will drop harmlessly onto the road, and not get on you, or the wheel, or anywhere else on the bike.

This is a breather system that works."

Mike and Stumpy in Michigan

[Terry_Finland]

Hello Guys,

I do have machismo 500 from India here in Finland. Itś having heavy oil leak from airfilter. Do you guys have any picture or videos showing how to fix this issue?
 kind regards,
Terry

[Adrian II]

OK, you have got a blocked main breather pipe. It will be clogged with emulsified oil residue/mayonnaise/elephant snot.

When the crankcase can't breathe through its main breather pipe (the one off the top of the oil tank), it looks for another route to vent. Unfortunately, with the factory set-up the only route available is up the oil return pipe from the catch-can, which enters the engine at the back of the timing chest. There's a small duck-bill on the return pipe stub inside the timing chest, which is SUPPOSED to stop oil being forced back up the pipe, and it fails miserably.

Once oil DOES start getting pumped up the return pipe if fills the catch-can, and from there it flows up the hose that links the catch-can to the air filter box, and then onto the garage floor or your rear tyre.

My Electra-X (very similar to the A500 Machismo, some different tin-ware) did exactly the same.

Your best hope is to rip out the old breather catch-can and pipework, plug the return pipe stub at the back of the timing chest and fit THIS.



The short 90° hose bend fits onto the breather stub on top of the oil tank. From there it connects to a one-way or non-return valve, and that it turn is fitted to a longer piece of hose which runs along the rear chain guard to the back of the motorcycle. Just needs three hose lips and something to fix the end of the hose in position.

If you can, go over to the AVL section of the forum and say "Hi", with a picture of your Machismo if possible.

A.

[Karl Childers]

 Instead of blocking off the return line  use a barbed T fitting and connect it to the line you are using from the oil tank vent and routed to the back fender. From what I can see that would get you more direct venting to the crankcase as well. Unless I'm mistaken there is no seal between the crank case and timing chest.

[AzCal Retred]

I tried several of these fixes with limited results. After I installed an Hitchcock's forged piston and steel rings on a new alloy cylinder, no more Nivea. The steel rings actually sealed. The combustion byproduct water vapor was now mostly going out the exhaust, not squeezing into the relatively cool crankcase & building up, then being whipping into mayonnaise, then splooging out the vent line along with the other blow-by gasses. Now I just need to install an intake valve seal to take care of the oil being sucked in by that route. The H's "separator" oil fill extension definitely makes it easier to top off the oil tank though...

[Karl Childers]

I tried several of these fixes with limited results. After I installed an Hitchcock's forged piston and steel rings on a new alloy cylinder, no more Nivea. The steel rings actually sealed. The combustion byproduct water vapor was now mostly going out the exhaust, not squeezing into the relatively cool crankcase & building up, then being whipping into mayonnaise, then splooging out the vent line along with the other blow-by gasses. Now I just need to install an intake valve seal to take care of the oil being sucked in by that route. The H's "separator" oil fill extension definitely makes it easier to top off the oil tank though...

Somewhere in the the not to far off future I want to change the piston, barrel and rings out as you have for the reasons you mention in your post plus I am reading too many posts about the stock pistons breaking to make me feel comfortable about running one for too long.

[AzCal Retred]

The stock Velveeta pistons seem to have multifunctional failure modes, seizing under a gradual climb situation, dropping skirts, and shedding the crown as well. For about $500 USD you add a lot of thermal & mechanical toughness to the motor, as well as gaining peace of mind. If I had a 5-speed I'd likely have gotten the 8.5/1 slug. Then you could retard the intake cam & have some extra RPM & HP to play with. You'd have a nice selection of ratios to fine tune road speed & load. My 4-speeds are "deliberate" shifters with agrarian ratios, useful but pragmatic, so I got the 6.5/1 set up instead. It works for my needs.

[Karl Childers]

The stock Velveeta pistons seem to have multifunctional failure modes, seizing under a gradual climb situation, dropping skirts, and shedding the crown as well. For about $500 USD you add a lot of thermal & mechanical toughness to the motor, as well as gaining peace of mind. If I had a 5-speed I'd likely have gotten the 8.5/1 slug. Then you could retard the intake cam & have some extra RPM & HP to play with. You'd have a nice selection of ratios to fine tune road speed & load. My 4-speeds are "deliberate" shifters with agrarian ratios, useful but pragmatic, so I got the 6.5/1 set up instead. It works for my needs.

When you buy the aluminum barrel does the piston come sized to the bore or will final machining need to be done?

[hpwaco]

Did the hose to the rear fender with a duck bill on my 02 ES.   Had a 70s Triumph 500 that ran the breather hose sans duck bill the same way.   Another one I should have kept!

[AzCal Retred]

@ #23: My "standard" unchecked alloy barrel I bought from CMW 12 years ago fit up to the new forged piston I bought from Hitchcocks this year with about 0.0045" - 0.0050" "slop", about right for a forged slug. Hitchcocks can sell you a "guaranteed fitted" set if you buy the miked/tested/checked barrel at the same time. Shoot them an e-mail with your name & membership number. The fitted barrel is cheaper than a bore job on an unchecked barrel. If you have any tappet noises, the alloy barrel does a fine job of amplifying them. Earplugs are my fix...   "Loud valves save lives!"