Tuesday, July 4, 2017

Little by Little...

There is an expression in the Cambodian highlands which states: Though the forest canopy spreads high and dense like a bronze cloud, the rain still falls on the snail.

The Hartman kart is progressing...naked chromoly steel instead of dull powder coating.  
The Aircraft Stripper worked great, but I had to use several applications for several tough areas, possibly caused by grease or other substance protecting them from the chemical. Apply, wait for curdle of paint, buff off.  I found that once the paint curdled, it could be removed by vigorously buffing back and forth with a red shop rag wrapped around the tubing. This left the surface clean and unharmed (unlike the brass wire wheel I used early on...😳😡).


SteveO suggested finishing with progressive levels of Scotchbrite pads until the surface is buttery and nearly reflective. I have tested this on a section and it does not take as long as I would have thought. But... there is a lot of tubing surface and hidden crevices.  Once the Sharkhide Metal Protectant arrives I will be able to seal the surface.  Without it the surface would quickly flash rust and ruin the surface. 






As enduro racing matured in the 1970s there were many different kart racers and manufacturers vying for the glory and fame of national championships. The most storied name is HARTMAN.  Designed and built by John Hartman in southern California, Hartman karts won dozens of national championships, many driven by his wife, Kathey.  The Hartman was THE hot ticket.  Every year innovations were added as karts were built for the Hartman factory team and for public sale.  The ad below shows the 1984 single could be purchased for just under $4,000!  That's almost $10,000 in 2017 dollars.
1984 Hartman Enduro advertisement. See it full size HERE


Here are a couple images from around 1979.  Notice the foot bumper supports are KH, which designated it as one Kathey would be driving.  




I am very blessed to have the original tanks, which should be iconic anodized blue.


But how to do it?  The best way would be to actually anodize the tanks, but that would be cost prohibitive. It was suggested to have them painted by an auto body shop. Again, too pricey.  Then I heard about Dupli-Color: MetalCast, a spray paint system that looks like authentic anodizing.  Amazing stuff!


As noted in previous posts the kart needed some major pieces, like an engine, clutch, and pipe. I purchased the engine and clutch from a fellow vintage Hartman racer.  The engine is a Yamaha KT100, which has been around since the late 1970s. The clutch is a Hegar Mystery clutch dating back to the same era.  He delivered them to my kart mentor, Rick, when they raced at Michigan International in May, and we arranged for me to make a visit to his shop to check them out.

Side note: My wonderful wife, Pam, gave me a wonderful gift for my 50th birthday... a ride in an IndyCar two-seater at the Indianapolis Motor Speedway in May.  We went to pole day of Qualifications then I had my ride on Tuesday.  Here are some photos.
Creditials?  We don't need credentials?  Actually, YOU DO!

Ready to GO!!  



I was hoping to get the ride with Mario, but no, the driver was Wade Cunningham in an older Dallara. That is OK, because it was still FREAKING AWESOME!!!!!  Dr. Tiffany Franks, president of Averett University and lifelong IndyCar fan, advised me to get the helmet back on the headrest before the ride started.  My brother, Steve, advised that I breathe!  Both were good advise and followed.  I had thought my legs would be beside the hips of the driver. OH NO... it is more of a crouching position, with knees at chest level. I got my helmet back and cocked a bit to the left to look in to the corner. 

As we headed out I was looking at the grass for reference on speed. First gear: "Been that fast." Second gear: "Been that fast!" Third gear, exiting turn one warm-up lane: "I HAVE NOT BEEN THAT FAST!!"  Bam! In no time were through Two and on the back stretch.  It is just so REAL!! I was breathing methodically and I am glad; even with the g-forces I was "in the moment" the whole time. The cars and movements are so smooth!  Dive into Three and my belly and head pulled to the right, but I was able to see the short chute wall coming and then going as we entered Four. The front straight is just glorious. Around for another full lap and it was over.  It was great.  THANK YOU, PAM!!  Pam's Dad, brother, and my brother, Steve, came to watch.  It was good to have them share the experience. 

On Monday we drove out to Comet Kart Sales to get an axle and look around. To me it felt sort of like a pilgrimage, since Dad would send me to get parts from the CKS truck at IRP, usually from a much younger Mark Dismore. I was expecting to buy a pipe for about $90, but found one for $30 in the cheap bin. It is not in the best of shape, and a bit rusty, but will clean up fine. It is an A4 for long tracks. Pam also bought me a Comet sweatshirt.

I did not to go to the Mid-Ohio race in order to save funds of the Hartman, but a few days later, I drove up to Rick's to spend a day checking out the engine.  I brought most of the kart parts with me to let Rick check them out, too. We spent most of the time getting the axle in, and all associated pieces, like the clutch, rear breaks, and things I had never seen before.  

I was concerned the original bearings may not be in good condition and had been considering ways to re-lube them or buy new.  They are not simple $6 bearings from Tractor Supply!!  These go for $60 each!  Rick took a look and noted that they are sealed bearings and seemed to have good movement. So he starts putting them in the frame... and it was off to the races.  Rick's gift is helping and sharing his vast knowledge with karters.  He is hands-on and teaches by example. I have learned to let him do what he wants... AND I will be happier with the result.

Bearing with ring.

Bearing installed with pin drilled into axle to prevent axle from slipping laterally.

Pin after smoothing.


Bearing with official locking collar installed.

Setting the brake disk.  

This is a 1-1/4" clutch on a 1/4" sleeve so it fits the 1" axle.   Thankfully, the 1/2" tall key was in the box of bolts which came with the kart.  We left the original bolts and safety wire on. 



Rear brake caliper.  Now I notice the fitting is a 90 degree... it should be on the front. It needs to be redone anyway.
Rick finished up the brake side of the axle before moving on to the engine side.  The space on that side is pretty tight since it contains the clutch, engine mount, and tire all in a small amount of space. He had suggested before that I might not be that satisfied with the Hegar Mystery Clutch. In his opinion it would be perfect for the Red Devil, but has a tendency to not keep settings.  We talked about switching to a Horstman axle oil clutch because it is easy to set and holds it.  It is one of the two main clutches used in enduro racing today, the other being SMC.  Setting it involves removing six bolts around the clutch and measuring the depth to the plate, then replacing the bolts. Then run the  engine with the tach to see where the stall speed is and set accordingly.  I have seen racers sitting in their karts in the pits doing the "WHAAAA, WHAAAA, WHAAAA..." then shut it off and smile. Yea... setting the clutch. 😀  Since the reasons for switching to this engine and kart are to keep me from thrashing and missing track time, I decided to go ahead and buy the Hortsman from Rick that day.
Rick and Hartman in his shop. Note the axle is in. The silver and black disk on axle next to the tire is the Hortsman clutch.
Installing it was a real eye-opener.  We had to get all the locking collars, clutch, engine mount,  hub, and tire spaced correctly so the driver sprocket on the engine lined up with the sprocket on the clutch. Here are a couple shots.  Yes, I am also moving to the more reliable and much more safe belt drive.
Bearing with its own locking collar then the clutch with belt sprocket.

Clutch, locking collar, engine mount bearing, then bearing locking collar.
These six bolts on the side of the clutch set the clutch. 
This process took quite awhile and involved putting on the engine, lining-up the sprockets, then lifting the engine off to add or subtract spacers on either side of the mount. I must have lifted and held up the engine 20 times... but look at these biceps!  

He also set up a couple tricks to cut down on weight.  I don't want to divulge them in case they are his secret tricks. 






Once that was done I was able to take this image of the engine in place and text it to Pam.  Due to the perspective of the shot, Pam thought the engine was sitting on the ground next to Rick. 

Here's the text exchange: 
Pam:  Is that the engine??
Todd: yep!
Pam: How fast will you be going?!?
Todd: faster
Pam: How much faster?
Todd: enough 😀

The engine is not as huge as it looks in the photo.  But I love the image... that the engine looks like a large block V1.  Didn't mean to do that. Here is a better look at it.


After getting the engine in place we figured out how the exhaust pipe was to be situated. The pipe is a A4 and should have a header length of 7.5"  (I may have that title wrong)

Next Rick checked out the engine. Now remember, this whole karting thing got started because Dad and I wanted a project to work on together, which was tearing down the McCulloch engine. We tore it down and put it back together. I thought that is what you did.  Since this Yamaha engine was used, I thought Rick would tear it down, replace bearings, etc. BUT NO... he looked through the exhaust port and found a very good pattern on the cylinder, meaning someone probably did a good job of prep before selling it.  So no need to tear it down.  He did remove the carb and put in a new gasket kit (I did not get any images). The Yamaha carb kits are cheap and readily available, as opposed to the Mac carb kits.




Then it was time to really check it out!  Crank it up!  Rick has a welding table which he bolts the engine onto, then start the engine (Sorry for the changing angle).  It started right up and heated up well. Rick said it "had good bark"... but is that good or bad?  He said it seemed like a very good engine.





One interesting point about this engine is that it has been flipped. Due to the normal placement of clutch and starter nut, KT100s are placed on the left hand side.  Sometime in the past the engine was taken apart and the bottom end and other parts turned 180 degrees. This was a wonderful design feature!

After getting all that set, he showed me a few of the little details which help keep things simple. He asked what bolts and nuts I was using for the floor pan. I showed him, but he strongly suggested using these 1/4"-28 serrated flange bolts with button head bolts.  The serrations dig into the aluminum plate and resist vibrations. Even with these, he suggested hitting each one with the green Lock-tite which seeps into threads.



Another detail new to me is using this fixture on the throttle cable tube. The orange plastic on the fixture captures the tubing without using a ferrel and compression nut.


Then he let me know that the steel tabs on the toe bumper need to be removed. They are hazardous in case I were to hit someone... they would become knives! So I need to use an angel grinder to cut off the tabs, then slowly grind and sand the tabs until they are not even seen. The tabs were used to support an early piece of bodywork.


And we were done...

Next is sealing the frame, then start to put things back on to the kart: steering, pans, pedals, etc.

Here are some photos of Rick's shop.  It has sooooo much character!














1 comment:

  1. Todd, been and worked in Rick's shop many times. He just does not stop working!

    ReplyDelete