I guess it will be easiest to start from the beginning since this will be an insanely long blog post. A little over a month ago, I decided I had to have some form of racing in my life to maintain sanity. So I got looking into many different forms of racing including: DSR’s, Spec Miatas, time attack, karting, and a few others. Well, after weighing my choices, I decided karting is what I wanted to try.
Karting had the lowest cost per day for track fees. It has the lowest cost of entry for equipment. And locally at least, it seemed to have the most numerous and closest competition. Now it was time to decide on a class. Shifters are the fastest, with the highest cost of operation. KT100 are underpowered and dated and do not have a lot of local participation. As I am 36, jr karts are out… That leaves the class I chose; Rotax Masters. The masters class, commonly referred to as “spec geezer”, is for 32+ people and has the highest minimum weight of the Rotax classes. I knew going in, it would not be possible to be a front runner given my weight disadvantage. Cars are affected much less by weight, but as I have always had a great time in
rental karts, it still won out.
The Rotax kart has a 125cc 2-stroke engine. Much like the shifters. However, unlike the shifters, it has only a centrifugal clutch rather than a transmission. The shifters have many other advantages to eek out more speed as well, such as better pipes (instead of a spec pipe), fatter chain (won’t make you faster, but seems to be much more reliable), front brakes (used to be allowed in Rotax, but are no longer),different tires (not sure they are better), better fuel, and more oil choices.
Kart pre-race in my garage. Prior to the abuse.
So given the differences, why did I choose the Rotax? Many reasons. But here are the big ones. The engine is sealed, so everyone theoretically has the same power. Also, unless you are a front runner fighting for points, the engine only needs new rings about once a year and needs a full rebuild every 2 years. Shifters seem like they get rings almost every race and a full build at least once a year if not more. Granted, with shifters you can do the work yourself, saving cost. But it involves a lot of work. Another big reason for me to choose the Rotax is because people I talked to about them say that shifters are more physically demanding and feel a lot more busy driving them. With the shifter, the acceleration is so much better that you can make up for mistakes. With the slower acceleration of the Rotax, you have to be smoother and take better lines. This is what I was led to believe anyway. More on that later. And finally, the biggest reason I chose Rotax Masters is because of the geezer class. It’s full of people that are older and more mature and running on equipment they had to pay for with their own money. In all the other classes, your equipment is getting beat up by kids driving as hard as their daddy’s wallet will allow. Granted, that is not all of the competitors, but there are a few bad apples that can ruin the day for a whole lot of other people.
So the decision was made. Rotax Masters is where I will get my feet wet in the world of racing karts. First step was to find a used kart. I looked on KSL and found a great candidate. Turns out, it was already sold. The guy that sold it said he had a couple others though. But after some discussion with him, I decided against his kart as it was a 30mm chassis and due to my weight it sounded like I wanted a 32mm chassis which is common in shifters, but much less common in the Rotax classes. So I went down to MSquared and asked them if they knew of any. Turns out some rich guy just bought one the previous year and it already was fitted for the big seat I need. He had only used it one day to break it in and never ridden it since because he had been busy having fun in his Porsche. They thought he may sell it for about $4500, but there was a chance he would not sell. So I waited for about a week on that one and the owner was in Mexico on vacation, and in the mean time another kart came up for sale from a guy I work with. It was older, but had the 32mm chassis and was run in the Rotax masters class 2 years ago. And I could get into that one for just $2,900. So I jumped on it.
Down the front straight
$2900 sounded like a great deal. The KSL guy was selling basically the same thing for $3500. And the newer nicer one for $4500 seemed like a huge price difference. That is, until I got tearing into my kart. This old Tony Kart had the old bumper. New one: $150. Add in the bolt system to mount the new bumper, there’s another $60. Battery is dead. Damn Rotax won’t let you get the $45 knock-off, you have to have the spec one for $90. Turns out Rotax has an updated clutch. Which is all fine and dandy, until the guys at the track say you can’t even run a race as a back-marker with the old one. Yeah, there’s another $550 to update the clutch. I have not done that yet however. Oh, and guess what, your airbox is the old model new one is another $90. Same filer, and base, just a different top half and it seems the biggest reason for changing it was just to make it look more sleek. $90 to look more sleek. Thanks, but no. I have not done that mod yet either. So of course I am not allowed to run. Even as a back-marker. Also, there is the brakes. This kart is old enough it was allowed to run with front brakes. Well, not anymore. So I have to switch to rear only brakes. Brake like $60. Got that, but have still been unable to find a cap to plug off the “T” on my current line, and the line is too short to remove the “T.” So either I find a $10 cap or buy another $60 line. Other than those things, everything seem to be ok. So once I do all that, I am in it almost $4,000 and have an 8 year old chassis. Makes that $4500 seem like a lot better deal now. You know what they say about the clarity of hind sight.
So I have my kart with a Large Ribtect (more like Ribdestroy) seat. First thing I need to do is fit the extra seat I got from the guy with the kart. Going from a Large to an extra extra large seat is quite a task on a racing kart. It’s so much wider, the mounts cannot be bent to work. You must cut them off and re-weld them. Also, the seat is now hitting the airbox on one side and interfering with the brake line on the other side. It already interfered with the brake line with the small seat, now it is not any worse, just different. Also, the battery must now be relocated. No room on this chassis behind the seat, or to the side. That leave just right in the middle between the pedals. I will be wanting more weight up front anyway I think, so that is fine with me. Turns out, it would be much better if I had a mill where I could machine out some proper spacers as my bracket method to hold onto the required stock battery box just bends the factory pile of thin garbage bracket. I had the kart at a friend’s house because he has a TIG welder and knows how to use it. So he helped me take care of that mess. He also bought a shifter from the same guy I bought my Rotax from.
This friend and I went in together on a garage out at Miller Motorsports I figured I needed this extra space not only due to not having a trailer or a way to haul a trailer, but also because it is out away from my house. It’s my man cave until I can afford a house with my own. As it turns out, I very much enjoy having a man cave at a race track. Working on a kart with racecars doing what they do best as your background noise can’t be beat.
So once the seat was mounted, I moved the kart out to the garage at the track. I went out there a couple days after work and got it all ready for my first test and tune on May 11th. You can’t believe how slow that week at work went. I got the water filled up, the gas filled and mixed, the new battery charged, new batteries in the Mychron3, brakes bled, that kind of stuff. Anyway, finally down to race day. Well, test and tune day. This is my first time ever in a non-rental garbage kart.
I push both our karts out to the track from our garage. For some stupid reason we are not allowed to drive them. We find a pit spot, and take the karts off the stand. Looks like I am out soon. I suit up and push the kart to the staging lane. The kart starts moving as soon as you start it. It is not supposed to do that. According to BRP (makers of Rotax) the clutch is supposed to engage at 4,000 RPM. Not at 1,500. Also, the whole way down the staging lane, the kart is acting like it wants to die. I can’t go full throttle or RPM drops. This is going to suck… But as luck would have it, as soon as I hit the end of the staging lane and get on track, the kart comes alive. It’s not accelerating anything like the turbo snowmobiles of my past, but it feels good. Especially since this acceleration is happening mid-corner off the race line where there is little traction. The steering feels a lot like the rental karts, which is to say it has a shit-ton of caster trying to rip the wheel out of your hand. As the lap progresses, the carb seems to clean out and the kart runs better and better. Then near the end of the session, it start bogging real bad on the straight. It turns out my fastest lap time was a 1:01.1. Holy crap, that was fun. And holy crap, my kart is running rich. So rich there is 2-stroke puke all over the back of my helmet and the back of the kart. I can’t wait to go back out. I can barely breathe and the ball of my hands feel like I smashed them in a vise. But wow, I must get back out there. So much fun…
2 Stroke puke from running crazy rich
I ran 2 sessions, then let my friend take it out for my 3rd session to see what he thought. He found it to be very loose in the rear, which I thought was odd as it felt very planted for me. But I outweigh him by about 80 lbs. I believe he beat me by almost 2 seconds at that point. Then I drove it a 4th session and when I brought it back in, I noticed it was dripping. Turns out Rotax has a cheap thin garbage bracket besides the battery box. My airbox bracket had been bent from my leg hitting it in left hand sweepers to the point that it had punctured my radiator. I bent it clear of the radiator and the radiator was not leaking real bad and water temps never got too high, so I took it out for a 5th session. Very wounded by now. Both me and the kart. I ended up only running a few laps because I started smelling something (probably nothing) and didn’t want the radiator issue to cost me an engine, so I pulled it in. Turns out I turned my fastest lap of the day in those few laps. I got down to a 54.4 second lap. So I knocked 6.7 seconds off my fastest lap from the first session. Not bad. I felt exhausted, yet excited. I was already looking forward to the next day I could get out on track. It turns out on Saturday, the class winner in my class turned a 47.4 fastest lap. So I of course still have a ways to go to be competitive. But even as slow as I was, my only regret is not getting the newer kart for a little more money. For reference, the fastest shifters were running 44.0 lap times. Also, when I weighed, my kart was just over 195 lbs with 1/2 tank of gas. Together, me and the kart were 68 lbs over class minimum. I think beefing up arm strength and lowering my weight will provide the biggest improvements.
Stupid bracket design
We’ll see if one of these bad boys helps at all with hand and arm strength 🙂