Kart Maintenance

[Fan]

I'm about to take delivery of a 100cc kart which requires a full rebuild. Im' planning to do this over the winter and thought that it may be a good opportunity to start a thread (I did look to see if there were any old ones) which may be of use to other people whilst I ask questions which hopefully someone can answer!

To start off with, a few quick questions:

1) I'm looking to get the frame repainted - what should I expect to pay?

2) How should one go about storing an engine?

3) The axle looks like it needs a clean up, what is the best way to do so and stop it from rusting?

4) The exhaust is rusty, how do you clean it?

Thanks for your help and I'll post some more questions as I run into difficulties!

[David Brand]

Originally Posted by Fan

I'm about to take delivery of a 100cc kart which requires a full rebuild. Im' planning to do this over the winter and thought that it may be a good opportunity to start a thread (I did look to see if there were any old ones) which may be of use to other people whilst I ask questions which hopefully someone can answer!

To start off with, a few quick questions:

1) I'm looking to get the frame repainted - what should I expect to pay?

2) How should one go about storing an engine?

3) The axle looks like it needs a clean up, what is the best way to do so and stop it from rusting?

4) The exhaust is rusty, how do you clean it?

Thanks for your help and I'll post some more questions as I run into difficulties!

1) Shouldn't cost too much, hard to say. Best thing is a sandblast & powdercoat.

2) Best to run some fuel through it then seal up the exhaust port & carby with clean rags or cling wrap the whole engine

3) Take the axle to a kart or machine shop and get them to lightly linish the surface to remove rust and burrs, then rub down with some WD40 or water dispersant/lubricant to prevent rust re-occurring.

4) Sand the rust off the exhaust and get some high temperature paint (black) and paint the exhaust to prevent rusting.

[ghinzani]

Good thread idea! and well covered David. Can I ask whereabouts you are going to run this 100? A lot of places are iffy about them you see - might be worth modifying the exhaust with a mini-moto silencer or the like whilst you are rebuilding it. Regarding the frame, defo go for a powder coat, but say to the sprayers you will have whatever colour they are doing next as a bulk order - probably save yourself a few bob.

[Fan]

Thanks for the advice chaps. I got the kart over the weekend and will start stripping it down this week.

I live in Spain so I'll be using it as a test kart at my local track. I made sure that they were happy about having a 100cc kart on their circuit before buying it and I also had to make sure that they were able to rebuild rotary valve 100cc engines as it's not something that I can/want to do.

With regards to the axle, I seem to remember from my karting days back in the 90's that there was a type of paper (I don't think it was sand paper) which could be used to get rust off the axle, or am I imagining it?

Plenty more questions to come as I take bits off the kart. Thanks again for your advice.

[ghinzani]

emery cloth?

[Fan]

Yes, I think that's the one. I'll see if I can get some at the local shop. Off to the kart circuit tomorrow to see what bits I can buy locally.

[jjordan]

If you decide on emory cloth, get as fine as is possible, use a little wd-40 or the like as it will help keep the cloth clean and cuts better. Chuck it up in a small lathe if available and try not to touch it with your hands before you can get some lubricant wiped on. I sand the rusty parts on my exhaust and then spray it with barbeque grill/flat black from the hardware. Allows me to "touch it up" through out the year. I stripped my one frame and then painted it with clear, looked good till it started to chip(and they will all chip), and then that starts a peel. Engines will usually always "store" fine, carburetors however is another story. I have heard that the best is to run gasoline through them unit it runs dry and then go back through, with the bowl/top off and shoot wd-40 through the ports/jets/tubes/etc. The alchohol we run especially does funky stuff in the jets/ports if allowed to dry some. sometimes gasoline isn't possible, but in a premix engine it won't take long for the oil/gas to start seperating so it needs to come out. Put your chain in an old coffee can with some oil covering it and just let it soak (after it is clean). on the stand, i raise the rear of the kart higher than the master cylinder, and with clean fluid filling a clear squeeze bottle with a clear hose attached to the beeders, crack the bleeder and force fluid from the back brakes to the master cylinder. Alot easier about trapping air (NOT) and getting the freshest fluid out where it seems it needs it most ( probably just my imagination). New bolts and nuts are a luxury, but usually pay off by the end of a long season. All sealed bearings get dirt in them, if you can figure a way to get the sheilds off without destroying them, it will help in keeping them flushed/clean. i have gone so far as to get the very small syringes at the drug store to inject cleaner/lube behind the sheilds (the drugest asked what I wanted them for, so I told him. He just stared at me and got me what I wanted rather dryly.)

[Fan]

Thanks for the advice jjordan. I've stripped the kart completely and will take it to be sand blasted and painted later this week.

I have an old Rotax rotary valve engine (ex Formula Super A, I think) which requires a rebuild and will do so quite often if I run once a week for an hour. I'm looking for a 2nd engine to use for the majority of the time. It must be 100cc and very reliable - long gaps between rebuilds is ideal.

Does anyone know of an engine which I could pick up on the cheap and will just run and run. Is a TKM engine the best option?

Thanks again for the advice.

[ghinzani]

Yep a TKM if you keep the revs low will go on and on if looked after. Should be a few un-extremed 100s left about the place that are cheap.

[Fan]

Originally Posted by ghinzani

Yep a TKM if you keep the revs low will go on and on if looked after. Should be a few un-extremed 100s left about the place that are cheap.

Thanks Ghinzani,

I'm also going to look at the Yamaha KT100 engines. I should get the frame back in a week or so, so I'll have plenty more questions in the next few weeks.

Thanks again

[Alex Hodgkinson]

Originally Posted by Fan

I have an old Rotax rotary valve engine (ex Formula Super A, I think) which requires a rebuild and will do so quite often if I run once a week for an hour.

If you run it oily and not out to the revs we used to run them to (22k as far as I remember) they will last a long time. We only used to rebuild them so often to keep them fresh. The highest wearing part used to be the skirt of the piston, which used to wear down as it went down past the huge exhaust ports we ran. Keep an eye on that (it's easy enough to pop the barrel off if it's air cooled) and keep it rich and it'll run for many many many hours.

NB: Run it rich. Don't try to stop it smoking. Rich rich rich rich!

[S.Moss]

Man i would of loved to have a go in an old air cooled super a kart. They sounds awesome compared to the KF's these days.

As people have said, keep the revs down, plenty of fuel and it'll last.

[jjordan]

In the beginning: the goal is to get something which is very reliable and adjustable. To start, nothing beats laps in your kart. Go out and learn what you can do, adjust on your kart and find out what you like and don't like, what it likes and doesn't like. Don't get somehthing that is maintenance intensive, yet. As you progress we tend to give up some reliability to gain some advantage, but in the beginning nothing will replace just getting out there and doing it. We run the TAG Leopard, harder you twist em, the more stuff breaks. But compared to some other stuff, it is reasonable maintenance wise. Do they run any TAG in England?

[Alex Hodgkinson]

Originally Posted by S.Moss

Man i would of loved to have a go in an old air cooled super a kart.

They were good days. I don't involve myself in karting any more, but the things we used to get up to were awesome. Highlight for me was running the Saetta SV31 disc valve engine with the disc located at the front, belt driven through 90 degrees! Water cooled with the radiator over on the left. Incredible bit of kit, won so many races with them yet never nipped one up.!

I feel sad it's all TAG and Max nowdays. Are the latest generation engines running screw adjustable carbs?

[ghinzani]

Originally Posted by Fan

Thanks Ghinzani,

I'm also going to look at the Yamaha KT100 engines. I should get the frame back in a week or so, so I'll have plenty more questions in the next few weeks.

Thanks again

Id avoid KT100s - clutch's awfully expensive, and not very powerful - kids engines in reality, all noise.

[Fan]

Thanks again for all the advice - I feel a lot better about the FSA engine, although I am on the look out for a cheap TKM as a back up.

My next question is about chassis protectors - do they work? Having just had the frame painted I'm keen to protect it so is this the best option? How many would I need per frame and where would you put them?

I see that people now use a brake disk protector - again, is it worth putting one on?

[Fan]

Another quick question: I'm looking for a lap timer, rev counter, etc. Is the Alfano Pro the way to go, or are their cheaper options?

[ghinzani]

Frame protectors work in my experience, if you site them correctly. Brake disc protectors are mandatory for racing nowadays, and worth it for the damage they stop to the discs.

Lap timers - Alfanos probably the cheapest these days, although a lot of people use Michron but they are even more expensive. If you are going to get a push start kart then Id say get your pusher to use a cheap stopwatch to start with. Theres better things to spend your money on.

[Fan]

Thanks Ghinzani. Where did you put the chassis protectors on your kart?

I've been offered a water cooled FA engine. Will these types of engines fit onto an old chassis from the 90's? Do they tend to run longer than aircooled engines? Are they easier to maintain?

[ghinzani]

I put one on the frame in line with the sprocket but forawrd and similar for the other side in front of the brake disc. Not sure about the water cooled engine, depends what it is. Might be more to go wrong, dont those FA engines have a belt driven water pump off of the axle? Then again as long as you arent stressing either engine, and running them oily they should go on for a bit. It should fit though, but its siting the rad etc. Depends how cheap it is ;-)

[Fan]

Apologies for the delay in any updates: The kart has been painted and I've put a new tank in. New nuts and bolts all the way around and I've managed to get the rust off the axle. I'm waiting for some new axle bearings to arrive (appear to have been lost in the post) and then I'll start putting the back end back together.

I need to get a seat and choose which engine i'll use. I have a Rotax rotary engine as well as a 100cc water cooled engine. I'll probably start with the water cooled first.

Does anyone know where I can find a diagram of how to put the radiator and pump onto the frame?

[Fan]

I'm about to start testing the kart but I wanted to first ask if anyone knows of a good way to clean sidepods. Mine are a bit old and have rubber, petrol, oil, etc on them which is proving a bit difficult to get off. Any ideas?

[ghinzani]

Ive heard acetate (nail varnish remover) works ok - but I'd be sparing with it! Otherwise does petrol not get the rubber off? To be honest Ive never bothered with mine as they always get walloped anyway ;-)

So whats it looking like? got any pics? where you going testing with it then?

[Fan]

Originally Posted by ghinzani

Ive heard acetate (nail varnish remover) works ok - but I'd be sparing with it! Otherwise does petrol not get the rubber off? To be honest Ive never bothered with mine as they always get walloped anyway ;-)

So whats it looking like? got any pics? where you going testing with it then?

Hi Ghinzani,

nail varnish seems to be doing the trick. Thanks!

I'll post some pictures over the next few days. The kart is looking good. Just had the rotary valve engine rebuilt and got ripped off nicely by the engine builder - £360 to put a new piston in...

I live in Spain so I'll be testing it at my local circuit. Do you know how I should calculate the correct sprocket to use? I want to put as little stress on the engine as possible.

The axle seems to be quite stiff. I put new bearings in an it doesn't roll freely. It looks as though the actual bearings are rubbing against the bearing mounts. Is it possible to get the wrong type of 40mm bearings?

The bumper is a little lose no matter how much I tighten the bolts. Is there a chance that an internat nut has come lose in the frame?

Apart from that I'm getting the carb rebuilt and then I'll be off testing...

[ghinzani]

re the gearing, try and find out what other people are running in similar classes (say rotax) and go longer. If you find their front and rear sprocket sizes then you can divide them by each other which will give you a figure which you can then multiply by your front sprocket and add 5 or 8 teeth to it if you want to be gentle.

Not sure on the bearings, most 40mm Ive had have been universal, its just the mounts that differ for reach kart. Again not sure about a nut in the frame, we use clips mainly now over here. Some pics would help ;-)