Harold Bawlzangya Racing

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Dimming the running light

Not only was the running light too bright, but with it mounted so high is was almost blinding at night.

With no Radio Shacks nearby, I got this from Amazon for $6.80.

After experimenting with different resistors and different combinations, I settled on two 2K ohm resistors wired in series.

Now I have a running light:

 

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Speedometer

I am going to finally cover up this opening in the electric dash:

I am going to try and use as much of my failed shroud as I can.  The first cut is always the hardest:

I am going to get the sensor and magnet mounted first.  I didn’t want to have to drill anything on the Jake’s spindles or weld anything, so I mounted the magnet to one of the bolts holding the disk in place.  I doubt that this extra weight so close to the center of the wheel will cause much of an imbalance.

I made up this bracket that will be bolted in place on the spindle:

And here is where this bracket mounts:

I made a cutout for the base of the computer:

Fits well:

I’m using a strap across the bottom two mounting bolts to hold the base in place:

I didn’t polish the face of the plate, but used some finer sandpaper to get some of the grinding marks out:

This computer goes down to centimeters.  I measured the circumference of my tire and come up with 143.5 cm.  I can only add whole numbers, so I went with 144 cm.  Opened the GPS app on my phone and drove around the neighborhood.  This should be about the most accurate test of the GPS as there aren’t any trees in the way and most of the almost one mile loop is straight.

And then I went for a drive on the paths through the woods.  The discrepancy wasn’t too bad:

Holy Crap – that is some serious run-out

A couple of weeks ago I noticed the disk brakes making some noise right at the start of a drive. It would only do it when the brakes were cold and go away after a minute.  Yesterday I figured I would finally look into why they have suddenly started making noise.  I started with the drivers side wheel in the air and when I spun the tire, I was amazed at how much the caliper was rocking back and forth.  I couldn’t believe how warped the rotor was.

I pulled the tire off and then got the rotor off.  When I checked the rotor, it wasn’t warped.  I then broke out the dial indicator.  There was no good place to mount the indicator on the front suspension, luckily the big anvil provided a solid base.

So after getting it set-up, this is what I find:

 

 

At this point I thought the hub must be warped.  I popped out the spacer that was short and traded places with the one on the other side.  When I spun the hub around again, the same spacer in a different location was still coming up low.  So now it looks like the spacer is the problem.  I pulled all 4 spacers and checked the hub. It looked good.

Taking the spacers to the table saw top, I found that the shoulders weren’t the same.

I don’t have a lathe or a mill, so I improvised with what I do have – a file and a drill press.

After several hours of taking metal off, checking, taking metal off, checking, this was what I ended up with.  I am feeling pretty good about this.  When I rebuilt two-stroke cranks, the run-out spec was .001″ for most of them.  I am really close to that here:

I am kicking myself for not catching this when I installed the brakes.  I just didn’t hear anything and definitely didn’t have any vibration or pulsating from the pedal.  But now that I look at how the caliper is mounted, I see why.

The passenger side wasn’t nearly as bad, but I spent some time and got the run-out near .001″ as well.

 

Well that was short lived – shroud testing and fail.

This shroud took longer to make than it stayed on the cart.  Sunday I went to the local elementary school with a laser temp gun and a 10mm socket & ratchet to test the effectiveness of the shroud I made.

The engine was somewhat warm from an earlier ride. I took the shroud off since it was cool and then drove about a mile to the school.  Driving around the parking lot was 1.03 miles.  For all testing, I tried to maintain 20 mph and 3k RPM.

I did 4 laps and pulled over and took a temp reading.  I then did another 4 laps and did another reading. The results were pretty close to each other so I felt good about that.  I simply laid the shroud on top of the engine and didn’t bolt it down.  I didn’t want to impact the temp readings while I took the minute or two to remove the 3 bolts that held the shroud on.   With the shroud on, I drove 4 more laps, removed the shroud and took a temp reading in the same spot as before.  I put the shroud back on and did another 4 laps.  I pulled the shroud and took the final reading.

The results were not what I expected and had hoped for.  With the shroud on, the engine ran about 10 degrees hotter.

The laser temp guns read a little strange when you try to use them on shiny or semi-shiny surfaces.  So this morning I thought I would try something different.  I put one of the prob from my digital thermometers that I use for smoking in between 2 of the cylinder fins and then packed it in place with aluminum foil.

This time I drove around the neighborhood.  It is a mile circle that is relatively flat, so I can maintain a constant speed fairly well.  I thought I would go 15mph instead of the 20mph from yesterday.  I thought this might even the odds between the shroud and no shroud.  I had already been out for a 9 mile drive, so the engine was already warmed up.

 

With the temp probe in place and the shroud off, I drove around the neighborhood and took a picture of the temperature monitor as I pulled in front of the house.  After a mile at 15 mph, this was the temperature:

Since I could see the temperature without lifting the seat, I bolted the shroud on this time and went around the neighborhood again.  Another mile at 15 mph and this was the reading with the shroud on:

I don’t think my laser temp gun was very accurate and there are certainly some flaws with this digital thermometer test.  But since both methods showed that the engine was hotter with the shroud than without, that is good enough for me.  Clearly there is plenty of cooler air flowing up and around the engine compared to the confined warmer air that the fan is blowing around and down the cylinder head.  I would guess that if you drove 5 mph the results might be different.  But who only drives 5 mph?

 

 

Hopefully the last of the stainless steel work

I finally got two projects that have been on the back burner for a while done.  With those completed, all I have are stainless steel scraps and am just about out of gas.

The first project was making a shroud to better direct the airflow from the fan around and down the cooling fins.  I spent way more time than I thought it would take on this.  It isn’t pretty, but it works really well.  I tired to make the cover fit tight in areas I didn’t want air to escape from.  With the engine running, the air from the fan will blow off leaves off the ground directly under the engine.  Forcing that hot air down, instead of just the area under the seat should help cool things off.

This project went way faster than I expected. I’ve been meaning to cover up with mangled hole where I had to make the electric body fit the gas frame.

Luckily I had one piece of stainless that was just big enough to cover it.  I tapped the 4 holes so I could just thread in 4 SS bolts.

It is kind of hard to tell, but the cut end of each bolt is sitting below the surface of the plate.  That way I can weld them together but grind off the excess.

All done:

 

 

Mother nature is making it tough to get around

Strong winds 2 nights ago did this:

And then some storms last night did this one:

Oil recycling run

I went on a drive that started as just a trip to walmart to recycle some motor oil.

It was still cool so I went to Napa to get some fuel line and then back to Home Depot to get a propane cylinder.  14 miles later I was back at home.