Pictures of my mopeds on web site now

I now have pictures of my mopeds posted on my web site. Go to http://www.geocities.com/miniengine and click on 'Moped Adventures' in the site directory. We have some covered bridges in our county and we are going to plan trips with the mopeds this summer to visit them. Pictures of these adventures will be posted on the web site too. Any comments are welcome.

If it ain't broke, you're not trying hard enough.

Brian

Lamborn's Miniature Engines

Re: Pictures of my mopeds on web site now

Rob Hoehn /

Brian,

Noticed you have a 76 Batavus VA. I have a 76 Batavus VA Deluxe that I just bought a month ago. What work have you done on it so far?

Rob

76 Batavus VA

Rob,

I've taken the engine to a mechanic that is in love with the Batavus mopeds. He is going to shave about .080 off the head and open up the exhaust port. If you look at the exhaust port from the outside of the engine you will see it tapers just before it goes into the cylinder. He removes the taper which provides a natural casting line to follow for enlarging the port. The piston travels to about 1/4" of the top of the cylinder, so shaving the head to increase compression doesn't endanger the head or spark plug. The Laura engine is beefy enough to allow these modifications without shortening it's life.

Next comes the intake part of the engine. He takes the reed valve and mills away the web between the V. He then lengthens the reeds and enlarges the reed ports just a little. The intake manifold which had a brass sleeve in it on mine was also modified. I had a S23 carb. The S22/25 carb and intake manifold for this carb. are about 8mm in size. He takes the old carb and bores it and the manifold out to 8mm.

These modifications and some tinkering with the sprockets can get your dry clutch Bat. running in the high 30's with power for moderate hills.

I have more and will continue later.

Brian

76 Batavus VA

Rob,

I've taken the engine to a mechanic that is in love with the Batavus mopeds. He is going to shave about .080 off the head and open up the exhaust port. If you look at the exhaust port from the outside of the engine you will see it tapers just before it goes into the cylinder. He removes the taper which provides a natural casting line to follow for enlarging the port. The piston travels to about 1/4" of the top of the cylinder, so shaving the head to increase compression doesn't endanger the head or spark plug. The Laura engine is beefy enough to allow these modifications without shortening it's life.

Next comes the intake part of the engine. He takes the reed valve and mills away the web between the V. He then lengthens the reeds and enlarges the reed ports just a little. The intake manifold which had a brass sleeve in it on mine was also modified. I had a S23 carb. The S22/25 carb and intake manifold for this carb. are about 8mm in size. He takes the old carb and bores it and the manifold out to 8mm.

These modifications and some tinkering with the sprockets can get your dry clutch Bat. running in the high 30's with power for moderate hills.

I have more and will continue later.

Brian

76 Batavus VA

Rob,

I've taken the engine to a mechanic that is in love with the Batavus mopeds. He is going to shave about .080 off the head and open up the exhaust port. If you look at the exhaust port from the outside of the engine you will see it tapers just before it goes into the cylinder. He removes the taper which provides a natural casting line to follow for enlarging the port. The piston travels to about 1/4" of the top of the cylinder, so shaving the head to increase compression doesn't endanger the head or spark plug. The Laura engine is beefy enough to allow these modifications without shortening it's life.

Next comes the intake part of the engine. He takes the reed valve and mills away the web between the V. He then lengthens the reeds and enlarges the reed ports just a little. The intake manifold which had a brass sleeve in it was also modified. I had a S23 carb. The S22/25 carb and intake manifold for this carb. are about 8mm in size. He takes the old carb and bores it and the manifold out to 8mm.

These modifications and some tinkering with the sprockets can get your dry clutch Bat. running in the high 30's with power for moderate hills.

I have more and will continue later.

Brian

76 Batavus VA Part 2

I recently got a carcass of a 77 Batavus HS 50. This has most of the parts that I needed to complete my 76 Bat VA. The rear wheel bearing on the VA had destroyed the rear hub and brake to where I had to replace it with the HS 50's wheel. I traded pulleys and belt from the HS 50 also. The front forks are better on the HS 50 so a paint job and swap are in order there as well. A rear fender and tail light from the HS 50 and I should have a Bat VA fully restored. I will be posting pictures of the 77 Bat HS 50 that sacraficed it's life to let my VA live a while longer.

The old belt drive system was very out dated for it's time so don't let anyone fool you by asking top dollar for a parts Bat to get some spare parts for yours. When I started asking locals whether they knew of any old mopeds waiting for the junk pile, I was amazed by how many people knew where I could get my hands on some.

I'm sorry for the multiple posts of the last message. Aren't computers great?

Brian

Lamborn's Miniature Engines

http://www.geocities.com/miniengine

Re: 76 Batavus VA Part 2

Rob Hoehn /

Brian,

Sounds like some sweet modifications. I just took the engine apart on mine after being inspired by you. I am taking it to a machine shop to the the spark plug hole re-threaded (previous owner messed it up). I like the idea of getting rid of the taper in the exhaust port, I might do that also. I was wondering, is there supposed to be a head gasket on laura engine? I noticed that there wasn't one on mine but I thought that some mopeds didn't have them. Thanks.

rob

Re: 76 Batavus VA Part 2

I don't believe there is suppost to be a head gasket. I've had 3 engines apart and none of them had head gaskets either. The exploded view of the Laura engine in the Batavus service manual doesn't list one either. I usually sand the head and the cylinder jug with wet sandpaper taped to a piece of glass on the work bench. I saturate the sandpaper with a light oil, like 3 in 1 oil, and move the parts around in a circular motion. I've put them back together either with nothing or a very light coating of permatex, light enough that you don't see the permatex, and haven't seen any difference or leaking either way. If you keep the parts flat to the glass and work your way up to 800 grit sandpaper you should be fine.

Brian

Lamborn's Miniature Engines

http://www.geocities.com/miniengine

Re: 76 Batavus VA Part 2

Another thing you can try if it already hasn't been done, is to take the end off your exhaust pipe and take the inner disk out. This will give you more flow through your exhaust. It runs a little louder but is worth the gain you get.

If it ain't broke, you're not trying hard enough.

Brian

Lamborn's Miniature Engines

http:www.geocities.com/miniengine

Re: 76 Batavus VA Part 2

Rob Hoehn /

Brian,

Thanks for the advice. I have a question though. First, do you lightly sand the parts to help create a better seal? Also, what is permatex? I've never heard of that stuff before.

So I brought my head and engine into a machine shop yesterday(drove there with my Starflite.) They are fixing the spark plug thread issue right now with a permanent spacer. I asked them to take out the taper in the exhaust port and they told me that it would mess up the engine and that I shouldn't do it. I noticed that the port tapers in and then has a small 'ring' around it that further restricts it. It would seem to make sense that that little ring could at least be taken out without any problems. Anyway, thanks again, and I will keep you posted.

Rob

Re: Engine

Permatex is a brand of a form a gasket material. It's blue in color, smells like stinky feet, and comes in a tube like tooth paste. When dry it is like a blue rubbery boogie. It's used to help seal valve cover gaskets, oil pan gaskets and the like. It's been around for a coons age and can be bought at every automotive store. Like I said before I use it very sparingly but have come to realize that it really doesn't make a diffence if you get the head and cylinder jug mating surfaces flat.

The goal is to have your surfaces flat, not to sand for the sake of sanding. When I take an unknown engine apart I will sand the head and cylinder jug's mating surfaces to make sure they are flat and will produce a good seal. Unless you scratch the surface or think you may have a leak or a warped part it really isn't necessary. It does eleminate dought if you do it though. The method I use may differ from others, but I've found that around the shop, glass is about the only true flat surface. That said, with the glass on the work bench I lay a piece of sandpaper flat on the glass and tape it to the glass at the edges. I saturate the sandpaper with a light oil, like 3 -1 oil, place the head flat on the sandpaper and sand in a circular motion. Don't get over energetic and keep some down pressure on the head to keep in in full contact with the sandpaper. Start with 400 grit and move up through the grits and use 800 grit for your final sanding.

The mechanics at the shop are right. If you don't know what you're doing you can mess a good cylinder jug up. Here in lies the problem. When you mess with the exhaust port you must compensate on the intake side of your engine. Just increasing your exhaust port will make your engine run like shit. Now if you increase your flow on the intake side by modifying the reeds, intake manifold, and carburetor then you have something. This is also true of jetting up a carburetor. Unless you make provisions for more air to flow through your carb all you are really doing is running an extra rich mixture that will only foul your plug. How much is too much? What is the right ratio? These are questions that I've answered the hard way by screwing up a few cylinder jugs, reeds and carbs.

If you want to enjoy you Batavus and don't have replacement parts available if you screw up then don't try tinkering. I had a few sad stories before I finally got it right.

Brian

Lamborn's Miniature Engines

http://www.geocities.com/miniengine

Re: Engine

Rob Hoehn /

I never really thought about the flatness of the head and jug. When I look at it though, it all 'looks' pretty flat. It never seized or anything else, so I'm sure its fine anyway. I will get some permatex today when I am getting my new torque wrench...

Rob

Re: Engine

Yes, if your piston isn't scored then you probably haven't ever overheated your engine. The bad thing about carbon buildup is that it happens so slow that it can sneak up and bit you. When an engine carbons up it will start to run leaner and this will cause heat buildup. The exhaust port is the easiest way to check your carbon buildup. If you see carbon build up in the exhaust port chances are that you have some in the intake ports too. Just something to remember in the future.

Brian

Added exploded views of Laura engine

I just added some exploded views of the Laura engine to the web site. They can be viewed by going to http://www.geocities.com/miniengine . On the directory of the main page go to 'Moped Adventures'. I hope this information can help some of the Batavus owners.

Brian

Lamborn's Miniature Engines

http://www.geocities.com/miniengine

Re: Pictures of my mopeds on web site now

adrian edwards /

please will you send me a picture of a suzuki katana ay50w

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