Thursday, June 23, 2016

Mid-Ohio 2016





The last week before Mid-Ohio was not what I expected.  I had hoped to have lots of time to assemble the second engine, then get both engines started.  That didn't happen.

Before last year's Mid-Ohio race I decided to rebuild the brakes and change the brake fluid to DOT5 because it is easy to find and I didn't know for certain which o-rings had been used (wrong o-ring with wrong fluid could be very bad). Due to my mistakes rebuilding the left caliper, it was not a good result (see prior posts). After rebuilding the calipers all I needed to do was bleed them, but it just would not work.... bubbles would not go away...even with the kart standing upright against the wall for 24 hours.  Very frustrating!


Also, I did not like the look of the left caliper.  The space between the puck housing and the platter was not consistent which made me think it would pinch. The brake system on the Hartman frame had been set up for the mineral oil RED fluid, so I decided to replace the left caliper and both master cylinders with those.  Disassemble, clean, dry, buy o-rings, change o-rings, reassemble, install, bleed. All that took most of a day.  And the bleed was still not working. ARRRRRGGGHHHH!!!

Then on what should have been packing day I decided to call Rick Chapman about the clutch sprocket being angles differently from the axle sprocket.  They were visibly off.
The sprocket on clutch was off about 2 degrees
Level on Axle

Level on engine mount -- high to the right

He agreed it was a problem, so I used a level and confirmed it was way off, and pulled out another motor mount and mount support from Dad's stash.  As I compared the used and "new" support, I found out the old one was bent just ever so slightly.  The new pieces were perfectly level!  YEAAAA!!!!


I had noticed about half the shoe material a clutch arm was missing.  It worked fine last year but still wanted to replace it. I found a piece of old shoe material on a vintage, unused arm.  To use it I had to drill out the rivets, then rivet it into place on the good arm.  I went through all this because after last year I contacted Steve O'Hara and asked him to check out video of the four-cycling and he suggested I add four teeth to the sprocket and also add weight to the clutch arms.  The sprockets came at Christmas and then I added three washers to each arm.

With that done, I finally got to packing which went on until near midnight.

We were fortunate to be able to use HI-LO camper borrowed from friends in order to stay at the track... right in front of the garage...and save hotel money.

We went through a huge hail storm near Athens, Ohio, but it was a good trip.  Just as we arrived at the track, another line of storms hit. This and electrical issues made getting the camper raised a long, wet slog and wasted my evening garage time reserved for final tinkering on the kart.  We were soaked and tired that evening.  We drove up to the shower building and found out "this is not KOA!"  Let's just say they were adequate... for that night.  The bright point was receiving the kart stand from Rick. Such a huge help!!   Thanks Rick!!


Practice day Friday morning was wonderful... just roll out of bed and walk 20 steps to the garage. No 4a.m. alarm, hotel breakfast, and 30 minute drive to the track. After the 7:30a.m. drivers meeting I spent the morning safety wiring the brakes and bleeding the brakes.  Bleeding was still not working well, so I asked Rick and Colm Higgins.  Colm suggested replacing a brake line which had a coupling in the middle of it, so I did the change with a piece from... Rick.  I had been trying to do the bleeding as shown in earlier posts, but it just would not work.  Rick suggested bleeding the old way... like on a car... takes two people... pump peddle-crack bleeder-let out air-close-pump-until all air is out.  Pam helped and it was done in under five minutes.  Finally, I was all ready and only missed a couple practice sessions.

Rick started the kart at the garage just to make sure it would fire.  It actually idled! After we pushed down to the grid, Pam used the new starter to start me...fired right off and the engine was strong... until I headed down the pits... and it slowly sputtered and died.  I was very frustrated... The next practice session I set the needles to my normal settings and it was very strong down the pits and onto the track, up the hill and around the Keyhole. Then down the back stretch it four-cycled, as normal, then strong up the Roller-Coaster to the left hander. CLANG-CLANG-CLANG... Just like last year...Chain off again... same spot!!!  I had to wait out that practice behind the guardrail.

The new sprocket hub must have moved!  I tightened the crap out of that thing and added thread-lock to it.  Back at the garage I was cleaning the grass off and studying the dang sprocket hub.  The space between the sprocket and the tire seemed not to have changed... but.. but.. that doesn't make sense.  DING!! then it all became clear: The motor mount had moved!  All the problems last year and this year were due to FORGETTING to put locking collars on the axle on either side of the engine mount when I rebuilt the axle bearings OVER A YEAR AGO!  I looked through early photos from the kart restoration blog and found this photo of Dad's finger... explaining locking collars!
That is Dad's finger, the motor mount, and one of two locking collars - during disassembly


UGHHHHHHHH!!!!  I felt so stupid.  Another huge, big lesson.  Then I spent a while walking around to different garages asking and begging for two 1" locking collars. Finally, I found ONE in Rick's stash and just moved one already on the axle over about 1/8".  The mount is not moving now!!!  It was about this time Rick suggested I retire this kart and engine to upgrade to the Hartman and a Yamaha. He told the same thing to Pam after she expressed her frustrations.


Is that a locking collar...YES!


I got out one session and it ran great and the chain did not come off!!!  That was all for Friday. Lots of frustration, but things got worked out.  That's what practice days are for, right?!

Saturday started like Friday... roll out and go to the garage.  After the driver's meeting I was getting the kart ready in the garage and saw my brother Steve trying to find a parking place, just before the first practice.  I pushed down to the pits while Pam was still getting ready and a karter (Low Budget Racing) from the next group started me just as Steve walked up.  A practice without a hitch!!!  After I pulled in and got parked in the pits, I greeted Steve then tried to be a real karter by "cutting the plug" to check how rich the fuel mixture was.  Maybe just a bit rich. Steve tried to start me for the next session but it would not fire... In the excitement I had not tightened the spark plug!!  With that taken care of I was able to get out a little.

Just before my first race Pam left to see her family nearby in Columbus.

I was all ready for my first race, which was Race 2, in the Vintage USA Piston Port class for 100cc engines.  This class combines the vintage McCulloch engines and vintage foreign engines, but, as always, we are in with modern karts.  This class was affectionately called the Geriatric Ward!


It started right up on and pulled great off the line and up the hill.  Being the slowest and last kart off the grid, I had a great view of dozens of karts heading into the Keyhole - dodging and weaving for position.  I ran two laps very strong, then I in anticipation of the four-cycling on the back straight, I leaned it out, but the needle felt like it had moved.  I tweaked it going down the straight but had to stop at the right hand turn heading up the Roller-Coaster... but the throttle did not get any response and by the top of the hill all I could hear was the piston - fooop foooop fooooop foooooop foooop.  OH Crap!!  I finally stuck it!!  So again I watched the rest of the race from the same spot... last year when the chain came off.

Back at the garage I told Steve all about it... running great... getting hot temps... loose needle.  I was thinking about pulling the engine when he suggested we see it would start.  Fired right off!!  Thank the LORD!!!  I was so relieved... so we pulled the Hi needle and I got out the needle gaskets and talked about it over lunch.  Before the next race we consulted with Rick on the needle gaskets, which he said to double up. Then I told him there was gunk in the fuel line.  I showed him an in-line gas filter I got from Comet Kart Sales and asked if it was good idea?  He asked if the engine was being effected? "No."  Then he asked if I wanted to get rid of the gunk?  "Yes."  "Then close your eyes!" he said back.  He reemphasized what he had told me several times... "don't over think it!" and "if it's working, don't touch it!"  So we went back to garage and relaxed.  Pam got back in time for the second race. As we waited I got up to do something to the kart and Pam shouted, "NO TINKERING!!"
Waiting in line for the scales after the race. John Copeland just ahead.
My second race was Race 5, the Vintage Unlimited for vintage engines up to 125cc.  My Mac is 100cc so I still count, but I am even more slow than the rest of the modern karts in the race. As we waited in line to get to the starting grid, I noticed a man and woman on the garage balcony waving at someone behind us. They looked like team owners. I slyly told Pam about them, then noticed her cousin Deana weaving through the karts towards us! What a great surprise!!  She had just been with them and they trekked up to the track to see me race.  Very special!!











I started strong, worked with the Hi needle every lap, and finished strong!!  Seeing friends and family cheering on the wall is sooo enjoyable!!  It ran so very strong, but I had to watch the temperature.  But I noticed the heat depended on the type of track I was on and how aggressive I was.  A-HA!  I figured out I could lean the Hi needle on the back stretch then clean out the carb before the turn to get the power back.  After the race lots of people gave me congratulations and we hung out with Mike and Deana in the garage.  He had lots of questions... which I was happy to answer!! He seemed to really enjoy this new experience.  I enjoyed getting to know him a bit better.

After they left Pam made spaghetti, and we had a few hours of talking with Steve before he headed home.  It was so very enjoyable to have him there to share the experience.  It's nostalgic but very different as adults.  And living several states apart, it was the most time we have spent together in decades.
Steve and Me from last year

Sunday started like the other days, but before the first practice Rick asked how it was running. I told him about tweaking with the Hi needle, but he seemed not to like me doing that.  He leaned down and turned both needles ever so slightly... probably 1/16th!  Every lap was very strong and NO four-cycling on the back stretch!!  Just that much changed the whole day.

Race 1 was very strong!!  I did richen the mixture just a bit to keep the temp down, but my best times decreased by FOUR SECONDS!!  VERY FUN!!!  I was able to draft with a slow kart from the Briggs and Stratton class until I had to worry about temps.


As we were on the grid for Race 2, I looked down and saw a clutch cover bolt sticking out!!  YIKES!!  Then another bolt was missing!!  Thankfully, Mark d'Elia ran to his pit and brought back spare parts and tools. THANK YOU, MARK!!!  Although "NO TINKERING!"  is our new catch phrase, we found out there is some necessary tinkering between races.  A couple people suggested that I use Lock-tite on the bolts, but I told them that I did!  That probably meant the clutch was super hot and melted the Lock-tite.

The whole race the engine still was pulling strong but I could feel heat on my shoulder and the readings were getting up to 400*F and beyond.  I wanted to finish so I allowed the engine to relax on the backstretch a bit.  And I did finish!!  That was 3 out of 4 finishes!!  Amazing how well it all runs when the kinks are worked out!!

Then it was clean up time.  We packed up and headed to the hotel for a relaxing evening and nice, hot, long (and private) showers.   AAAhhhhhhhhh!!

It the started out with some frustrations but ended up very well.  The Dart Kart Club offered a Package which I took advantage of: one price and I was able to get a Pit pass, Friday practice, and any race I could enter.  I doubled my races and saved some money.  Thanks DKC!!

Before last year's season, Dart Kart Club decided to quit WKA and go with AKRA as the sanctioning body. I really like the leaders.  The seem to genuinely want enduro/road racing to flourish.  This year they invited CES (Championship Enduro Series) from the Illinois-Oklahoma-Kansas area to Mid-Ohio.  They were set up in massive party tents in the paddock.
 That gave quite a boost to the number of entries.  It was reported there were over 500 entries! Best numbers since 2012.


With the bolts being loose or missing, I was afraid the clutch oil would be all gone, causing the hi temps.  After getting home I pulled the clutch cover and discovered most of the oil remained. Burnt and smelly!!  But some of the new shoe was missing... ground to a pulp by the rotating arms.  There were some chunks but most of it was a powder in the oil.  No wonder the clutch was hot!  Friction Friction  Friction!!!





I am carefully considering Rick's suggestion about putting Dad's Red Devil on the wall... it's a real trophy... for all the work with Dad, to all the races... finished and unfinished.  I have pulled the Hartman kart out and placed it on stands next to the Red Devil.  I can't wait to see what happens next...













Sunday, May 1, 2016

Flag is UP!

It's May! 

Only 29 days until the 100th running of the Greatest Spectacle in Racing.


And that means it's kart season.  WooHoo!!


Most of my time lately has been spent working on graphic design and letterpress projects.  ( Selfish plug: tagdesignstudios.com )

Christmas was a "KARTFEST!"  I received many kart related gifts including a new starter ( more of a Pam gift to herself since she will be using it), a GoPro camera, a new smoked helmet shield, two new chains, two new chain breakers, and several new sprockets.  All suggestions from my list.

Compared to last year I am way ahead as we approach Mid-Ohio in June.   Last year I did a full engine and brake rebuild, along with new axle bearings and adding the Digitron.  Not this year.  I will be testing for air leaks, pop-off, and check on timing.  Hopefully, that will be all before heading out.

I know it's silly... but one fun thing I put together over the winter was a new push stick. The one I created a couple years ago was steel tubing and bolted together... loosely. And with the tach/temp Digitron onto steering wheel now, the design was wrong and did not work as needed.  I found aluminum tubing at Home Depot then took it to a local tool/welding shop - Jerrett Welding - near Pam's workplace. The design came from the pushsticks engineered by the guys from Boston.
My new push stick 


The Boston guys' design




One of the problems I had last year was with the left brake.  It was always engaged and would not retract.  And brakes were spongy with only one caliper working effectively.  Over the winter I took an  Airheart brake caliper off the Hartman kart and got to know the mechanism much better.  Doing research on http://vintagekarts.com forums I found out even more from the kart veterans.  I also tracked down a vintage kart magazine article about the magic of Airheart brakes and the legendary "drag ring," which looks like a warped washer. Instead it is a highly engineered and machined means to keep the puck exactly the right clearance as it wears.
The Airheart retaining ring
One important thing was during rebuild to properly align the piston stem through the retaining ring as the piston is pressed back in.  Airheart sells a pilot, but of course I didn't want to spend the $24 for it.  I bought some brass tubing and had Jerrett Welding lathe it down to the proper dimension. Of course, I spent $30 on that.  Oh well!


Another important factor is not to "snag" or "catch" the piston stem as it is pushed through the drag ring. Many vintage guys suggested using a hydraulic press to install the piston (NEVER USE A HAMMER--woops! another rookie mistake), but after investigating and looking at videos on youtube.com I thought that was overkill. So I started thinking about how to make a small one.  Then BINGO! While at an antique store in northern Virginia I saw it... an antique bottle capper!  

It delivers nice, even pressure I can control and also feel if there is any "catching" in the process.  I purchased it for $12. The I made a tool from a PVC pipe fitting which gives a surface to press against during the "press out" process, flip it over, and use it for the "press in" process.  It works great. I am right proud of it!

Last week I took the offending caliper off the cart and worked through a couple things.  I replaced the bolts attaching the caliper to the frame from grade 5 to grade 8.  That's when I noticed washers between the two pieces of the caliper... which should not be there.
Where the extra washers were... 
Why are they there? Then I remembered that last year I had a hard time getting the piston all the way in, which would leave the brake puck sticking out about 1/16"...probably because I used a hammer and socket to "press in" the piston and the piston stem "caught" on the drag ring.  I must have "filled the gap" with the washers. With too much space the drag ring did its job too well and constantly caught the piston stem. NO Wonder the piston would not retract.

I took the caliper to the workbench and I pressed out the piston (the press worked great!), changed the o-ring seals, checked the retaining ring, and pressed it all back together in about 10 minutes. This time the piston pressed all the way in by hand. No need for extra washers.
Looking into the caliper at the drag ring with retaining ring removed
Looking into the caliper at the retaining ring, drag ring, and o-ring seal.
Piston and piston stem. Note the silver scratches on the stem made by the drag ring.

Bolt it back on, bleed it (thanks John Copeland), and all done in under an hour.
To bleed the brakes the master cylinder needs to be above the caliper, so I improvised and used a "get-along" to lift the front of the kart.

Tinkering and figuring out solutions are some of my favorite parts of karting.  OKAY... and racing!

Since I have two master cylinders, I use an adjustable linkage between the two.  Originally, it was designed to bias the front or rear brakes when this kart had four-wheel brakes. I am working on getting the two master cylinders to work exactly together.

With last years problems Van Gilder suggested biasing to the right brake and away from the left sticking one. I am going to ask Rick Chapman if he knows exactly how it works. It seems easy enough, but just making sure.

I have been dreaming of getting an automatic kart stand so I can work alone.  Then during a conversation with Rick he asked if I had a push stick. I said that I did but was dreaming of a kart lift. He has one and offered it to me for a great price.


It has a boat wench action so it will still be some work, but much better than lifting... and looking for help. :-)

One of the problems last year at Mid-Ohio was the chain. I dropped out of two races with a broken chain then a chain off the sprocket that clanged around and damaged the clutch sprocket. It actually cracked or broke off the tips of the hardened steel teeth on the clutch.

I asked Rick about it and he suggested I not use it. Fortunately, I have a second one from Dad's stash, but it did not have the bearing.  I identified it, looked all over for it, then Rick sent me three... for free. I found out how to press-in the bearing with a bolt and nut on youtube.

Due to the sprocket alignment problem last year, Rick suggested giving up on the Lemelo aluminum  oiler sprocket. It is a pain to align due to how it grips the axle.  Dad's stash had another light sprocket but it also had a tricky system.  I started looking for what Rich suggested - a sprocket with one sprocket head bolt for easy alignment. While looking for something else in the vintage stash bin, I saw something...


A never-opened GEM sprocket!  That's real NOS...NEW-OLD-STOCK!  Exactly what I needed.

Even before I got the kart running I had heard of setting-up the carb properly so it four-cycles at the end of the straight. At Mid-Ohio it does fine on the main straight but only lasts about 1/2 of the backstretch. So I sent a GoPro video of me at Mid-Ohio to Steve O'Hara, karting demigod, to ask for help. He was gracious and made two big suggestions:
  1. Since the engine was topping out at under 10,000 RPM, I should move up to a 64 tooth sprocket with the 14 tooth drive gear. This should allow higher revs. 
  2. The clutch was not engaging coming out of corners, so add weight to the clutch arms to get it to grab earlier.

To help with adjusting the carb, I have looked into using a remote carb adjuster.  I bought one over a year ago but had let it sit.  Recently, a vintage forum post asked about them and I joined in. SteveO posted some pictures of a set-up he used with great success using gears from remote control cars:
SteveO's set-up

SteveO's set-up

SteveO's set-up

I have finally found similar gears and am now in the middle making a bracket from aluminum. The larger gear ratio will allow me to get more torque to the High Speed needle for easy and precise adjustment.  We'll see how it goes.
future bracket being cut

19 tooth, 48 pitch, 5mm shaft R/C gear

57/36 tooth, 48 pitch, 5mm shaft R/C gear

57/36 tooth, 48 pitch, 5mm shaft R/C gear
Over the winter on a snow day I looked through Dad's old karting magazines looking for "how-to" articles. I found several that will help understand this old kart.  I also found several advertisements for the Red Devil karts back when they were "the kart" to have in the late 60s. As a graphic designer, they are very evocative of that era.






And... not everything is about karting:

video


video