July 26, 2014 at 8:52 pm #30950
After reading the suggestions thread and seeing people wanted some articles, i figured i would take on a task of making a little blog myself.
My history consist of starting out when i was 10 years old in dirt oval karts in Ohio and progressing my way to minisprints (600cc sprint cars on a smaller chassis) and i even owned a ARCA stockcar for a brief period of time where i realized real quick how much money it took to make things go around the track..
I’m now 25 and live in Texas with few racing options. I found a local track 10 minutes away that has a nice club and decided i would try my hand in karts again. I bought a 2002 Birel 125cc PRD fireball for a modest price and decided to give it a go.
After a few weeks of depleting money getting it back up to par i decided to take it out for a test session…
I couldn’t believe the fun and acceleration it provided. I’m new to the 2-stroke engines and im thoroughly impressed. The PRD is the “budget” engine package offered in the TAG class but it felt strong. I had a few problems on my first session. I had a fuel starvation problem and also ran into a small brake issue. The fuel starvation would happen on the long straight away on full throttle it seemed to cut out. I believe this was due to a venting issue. The other problem was the brakes went soft after bleeding them a couple hours prior to arriving at the track.
As i mention this is the first time to the track with a new (to me but old) kart. I have rebuilt the brakes, carb, and updated numerous parts. The mychron 3 plus that came with the kart isn’t operating correctly and has been sent to AIM for a refurb.
My first race is planned for Aug, 9th and i couldn’t be more excited. My sides hurt from the few laps i ran and i can already tell i need to be in better shape to compete to a quality standard. All in all i was impressed with the kart on the first outing and can’t wait to get back into the seat and get some track time.
I will try to keep a updated blog if anyone cares to follow i will continue to write up some articles of my progress and include some pictures. I figured since people seemed interested in some new articles maybe a few members could provide some. I will include some tech tips and setup tricks as i learn and come along. But beware, i have been out of the scene a while and some info might not be 100% correct.
In closing, im glad i rejoined a great racing community and hope to provide some knowledge and info to future racers.
July 28, 2014 at 8:43 am #31037Walt GiffordParticipant
The brake problem is probably due to heat. Try adding a cooling vent. Also, you might try lifting off the brakes faster, the kart might corner faster than you think.
FAA certified jet engine and aircraft technician,
Nicholson Speedway class champion 2001,
Yamaha KT100 Service Center,
41 years karting experience
July 28, 2014 at 12:38 pm #31051Daniel JusticeParticipant
The pain in your sides is likely from your ribs being against the sides of your seat, and in 2-strokes you’ll get a large amount of vibration into the seat and into your sides. You can alleviate this with a rib vest or protector. You shouldn’t need to be in peak physical condition for a PRD, but it’s always a good thing to shape up. Good luck and welcome back to karting.
July 28, 2014 at 3:50 pm #31065
Thanks for the replies and tips.
Walt, I believe the brake issue was a fault on my behalf. I had rebuilt the calipers earlier that day with new seals on the pitons and some fresh dot 4 fluid. I don’t think i got all the air out and the pedal was just soft.
I brought the kart in immediately and re-bled the brakes and had a pedal again, although it was a long pedal. My next step is to adjust where the brake lever connects to the master cylinder to alleviate that issue and hopefully have a stiffer feeling pedal.
The kart does corner quick but i had some very used tires for this basic shake down test session. My goal was to sort out any obvious issues before my first race (Aug. 9th)
As far as the soreness goes, i do have a rib protector i was just being stubborn and not using it. I was also a little more tense than i should have been just for the simple adrenaline rush of being on a track again for the first time in a few years.
I wasn’t expecting the acceleration the 125cc two stroke provided and was immediately grinning from ear to ear while gripping the steering wheel with white knuckles.
Seat time is a definite must before im remotely competitive but getting on the track was the first step to my long endeavor. I hope to run another test session before the race to work the final issues out and will hopefully be back to report some more progress.
July 28, 2014 at 4:12 pm #31067Brian DegulisParticipant
Austin use the rib vest. If you bruise your ribs you’ll be 4-5 weeks of no karting.
July 30, 2014 at 7:46 am #31162Boyd AthertonParticipant
Are you racing at NTK in Denton? I’m a member of NTK. Welcome to club. I bought a used kart with a PRD Fireball at the end of January. I did the last race of the winter series with it, then switched it to a clone/chonda. Now I’m running with a Animal in our box stock animal class and loving it. If we do brackets again in the winter series I’m planning on putting the PRD back on for some fun. The PRD is a strong motor and a blast, I just wanted to practice smooth driving and there’s a few very experienced guys in our animal class.
What gear are you running? You mentioned your mychron was broken so you probably don’t know max rpm.
On your cutting out issue, it sounds like the high speed needle is set a little lean. You can adjust the high speed needle while driving to dial it in just right. Here’s a link to the PRD manual that will help. The second link is to a PRD owners group in Australia. PRD is very popular over there. Tons of good tips to read on that site.
Hope this helps. Looking forward to hearing more about your experience.
I’ll be out of town for our August 9th race at NTK.
August 2, 2014 at 1:24 pm #31343
I’m in the central texas area. New Braunfels to be exact and will be racing at HCKC primarily.
The gearing is 10 tooth with a 93 on the rear. I believe i need to be running closer to a 87 from seat of the pants feel. I have just bought a EVO 3 mychron from a fellow Ekarter at a very reasonable price and will hopefully have that by next weekend (aug 9th).
I’m a budget racer and like to try to do more with less when i can. I take some enjoyment out of beating higher budget karts with dinosaur equipment.
I just purchased my trailer today and almost have it built, a harbor freight special..It came out pretty decent and i think it will do a fine job for its purpose. I will be hauling it with my auto x car…a miata :) so no problem finding me at the track.
This week i have been doing final prep to get it ready to race.
I have replaced throttle return spring, cleaned carb, put on fresh set of wheels and tires. The wheels and tires are brand new from the previous owner. He bought spoked wheels but the spokes didn’t allow me to put a wrench on the nut to tighten the wheel to the hub. I ended up taking a dremel tool and the sandpaper attachment and routing the holes a bit more so i plan on getting everything balanced soon.
I have been doing a lot of road racing on the Iracing.com simulator..Although Iracing will never give you the seat of the pants feel, i think it does a decent job of staying sharp mentally and will hopefully speed the process up on the track in real life of becoming quick.
Nothing too major to report back this week as im waiting for a proper data logger before i take it back out and do anymore testing. I will have a proper write up next week and ill get around to adding some pictures shortly of my process of getting back on track.
August 9, 2014 at 7:15 pm #31745
Well, im back for a update. As mentioned earlier i bought a “race ready” kart and had high hopes of racing it sooner than later. After $600 more spent it still is not race ready.
I have bought a second mychron 3 after the one that came with the kart didn’t work and wasn’t fixable. I was waiting on this to be installed before i took the kart back out.
So today i decided i was going to attempt to race the kart. I had 4 brand new MG yellow tires on new douglas wheels that came with the kart. I installed them and loaded up on my newly built harbor freight trailer and away i drove.
I get to the track and arrive to some impressive rigs. There was a toy hauler RV that probably has a nicer living room than my current living room. Numerous 20 ft+ enclosed trailers and expensive karts in them. I expected some of this but i was clearly outspent by everyone at the track. Most of the racers were in Denton preparing for next weeks Skusa race i was told so i thought i had gotten lucky and was going to get a nice practice night.
After filling the tires up with air i quickly found my RF tire had a small leak and would not hold air for much longer than 5 minutes.
I filled the tires up and put a little more air in the RF for a quick practice run. I zoomed off onto the track and quickly realized that my brakes were yet again soft. I decided to get onto the throttle any ways on the long back stretch to also find out my throttle cutting out under full throttle had not gone away.
I reverted to PRD recommended carb settings and it is still running pig rich, wet plug, oil out the exhaust and flooding when floored..
I limp my kart back to the pits and start tearing into the kart. I decided i would go through the carb to double check everything and spray it out. All looked well with the carb so i decided to lean it out via the needles.
I took of my leaky RF tire and replaced it with a worn out MG and figured i would run the rest of the night on that.
It is brutal hot in the Texas region right now so i took a break and sat and some cool AC when i heard my class was next on the grid.
I run to my rig and throw on my suit and rush to the grid.
I asked to tag the field since i had obvious issues and didn’t want to be in anyones path of rapid acceleration.
On the starting grid i had a bit of a time getting the kart started but managed to do so… This is it, im finally going to race this kart!
We take off for our one to two lap warm up before the heat starts. I take off and hit my freshly bled and working good brakes. They manage to slow me down in a appropriate way and im starting to think my luck is starting to turn. I hit the long back stretch and slowly get into the gas. Half throttle it is singing along beautifully so i go a little more….whooosh nothing but air flowing past my helmet and a cut out engine. I let the engine catch back up and get out of the throttle. Im not familiar enough to reach down to the carb by feel and adjust needles so im looking at the carb, trying to keep kart on track and look over my shoulder to get out of anyones way before i have more parts to replace..
I pass the start finish line and decide i would limp it in the first heat and just try to finish. As i pass the start finish line after the same symptoms persist on lap two im surprised to see the flagman give me the meatball flag. I pull to the side and ask what the problem was. The corner worker than bends over and pulls my dragging bumper off the ground. The bolt had come loose from the worn out bushings and now i have no bumper.
A $2 bolt has sent me home early. I figured it was time to pack up and try again for another test before i attempt another race day. As disappointing as it was i decided to take it back to the shop and try to work some bugs out of the engine.
I go to start the kart and a squeel from the clutch side when i hit the starter. The battery is low so i tried jumping it from a car battery. it turns over and the low pitch squeel is still there. I manually turn the crank and am relieved it isn’t a internal problem but more likely a clutch or starter gear problem. I pack up and go home, needless to say a very disappointing first outing.
In closing, im not surprised to run into road bumps as im starting out on a new path but didn’t expect these bumps. Murphys law will rear its ugly head but don’t get discouraged. I have been the new guy struggling at every turn and i have also been the experienced guy winning a lot of races. I can honestly say the guy running at the back of the field is usually working harder than the guy winning races. When you are winning things are going right. When losing you are chasing your tail wondering how to make things right. My saga will continue in a couple of weeks and i will be back with some more updates along the way.
As promised here a few photos i snapped of the kart and tow rig. The highlight of my night was the trailer not falling apart (the wheel bearings did heat up pretty good however)
August 2, 2014 at 7:26 pm #31367Matt DixonParticipant
Listen to your pants, I dont care what what track you are at with a PRD w/10-93 you are way out of gear. Start pulling teeth, a lot of them…
August 11, 2014 at 11:29 am #31809Evan FraserParticipant
Welcome to Sprint Karting! I’m glad you’re keeping a good attitude and keeping your chin up. I started out just as you did, with an old wreck of a 2002 Tonykart Mitox with a Rok 125 that needed a lot of work. For three years I towed my kart around with my car on a 30-year-old boat trailer (converted to haul karts) and was intimidated by all the big expensive rigs. Soon I learned that my fellow racers really aren’t that scary, and many of them would happily help me out with questions and tuning issues. Make some friends, have some fun.
In terms of tuning, obviously gearing is going to depend heavily on the track and the power curve of the motor but on my old Rok I ran 13-80. I think the guiding principle is you should be hitting the rev limiter at the end of the front straight.
Glad to hear your brakes are better. I had an incident where a fitting blew off and I had no brakes. It was messy.
Regarding your carb issues.. I don’t know a lot about the Tillotsen carbs but the principle is the same. Ask around for a good basic setup (needle position, main jet, emulsion tube, idle jet etc.) and then tune by your pants. I set mine to factory once and it was so rich it barely ran. Also I noticed in your pictures you have a conical air filter on your intake instead of a silencer. I’m not sure that would make a difference but I’d still buy the proper intake silencer.
Best of luck and keep us posted!
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August 11, 2014 at 12:17 pm #31813Dale DaughertyParticipant
Great, and here I was thinking I was going to be the only person out at Hill Country Kart Club pulling a Harbor Freight trailer with a Miata!
2010 Spirit [Birel] SP32 // SRS CR125 - Stock Honda [#08]
Hill Country Kart Club - New Braunfels, Texas - http://daledaugherty.wordpress.com/
August 11, 2014 at 4:52 pm #31832
What a coincidence. I thought i was for sure the only guy around towing a kart with a miata. I get all sorts of looks from people on the interstate and have people at gas stations wanting to talk about there 900cc motorcycle engine kart or something.
Thanks for making me not feel like such a black sheep. I love my miatas this is my 4th different mx5, all NA models though.
August 15, 2014 at 10:53 am #32038Michael ZahorskiParticipant
Sounds like we’ll be learning together out there and hanging out keeping out of everyone’s way the first few times out there. I’ll be racing at HCKC as well, and just bought a TaG kart a while back. I have a Parilla Leopard in an Intrepid Cruiser. I went out for my shake down run 2 weeks ago and had a blast, but didn’t walk away without my share of problems either. I’m just about done putting it back together and getting ready to test again.
August 27, 2014 at 10:59 pm #32765bob prinzoParticipant
if you had the carb apart,did you mess with the needle and spring under that little lever in the carb? have the pop off checked,if you want your topend back.settings should be around 1 7/8 on the low, 7/8 on the hi.popoff around 10-14.
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