Info - Frequently asked questions
Engine and carburetor
Can you really be competitive with an engine straight out of a box?
Yes, you can. It's sometimes really hard to believe. A good example is Joona-Oskari Juurikka in Alahärmä in 2016 when he put a brand new engine directly to final and set the 2nd fastest lap time even if it was broken in just on a trolley. Other good examples are Mikko Melkkilä in front row in Lievestuore in 2016 and Antti Ollikainen winning the same race in 2017. Tomi Tiilikainen was also extremely competitive at the same track in 2017. Even engines doens't mean that they're always equal. Engines wear and they need to be maintained properly. Engine which is not properly taken care of, can't ever be as good as an engine which has been taken care of. Equality means that everyone of them can be quick.
Is there a point in renting race engines?
Just because of extra performance, there's no point. However it's handy way to outsource responsibility and duty plus save in maintenance expenses of your own engine. In many cases you also get valuable information about other things such as carburettor and chassis settings. If you rent an engine from a reliable partner, you can be sure that someone has really checked everything and guarantees that reliability and performance are at optimum level. If you can do the maintenance yourself, renting engines is not recommended. Renting is also handy way to test a new class.
Can you be competitive abroad with Finnish engines?
In IAME International Final 2016 in Le Mans, France Finnish drivers drove top times with their own engines. Rental engines weren't faster at all. All tuning of the engines is banned also for the so called tuners, so not even they can do some magic tricks. High quality manufacturing process guarantees that there are no super special engines spoiling the market.
Can I buy engine from abroad?
You can buy your engine from anywhere and the participant is always responsible for the legality of the engine in scrutineering. The engines don't have ID cards and they're not sealed. The importer of the engine is not obligated to support and serve customers with warranty issues of engines that aren't imported by them.
What are new and old cables?
The new cable harness is more compact and faster to install. Pros are for sure easiness and speed of use but a con is the fact that it doesn't charge the battery any more. The old cable harness is slower to install, it requires some tools for ground cables and it has a bit more mass. The old cable charges the battery and the kart is started from a key. The new version has buttons for starting and stopping the engine. Things that affect on performance are 100-percently identical, so in that sense there's no point in upgrading or downgrading.
How do I tune the carburettor?
Good basic setup for the carburettor in factory settings is L 1,0 and H 1,15 meaning 1 hour/turn and 15 minutes when 60 minutes means one complete round. If there are long straights, usually you need to open the high (H) screw. If the engine isn't sharp with low rpm, you may need to close the low (L) screw. It's highly recommended to change the setting only by few minutes at the time and first try to go richer than leaner. A handy way to understand the carburation is to have an EGT (Exhaust Gas Temperature) sensor. In a flying start, you normally close the L screw by about 15 minutes and open it back during the first laps. This way, the engine is much sharper in the start after driving slowly on formation lap. The engine needs fuel to perform effectively and going with too lean carburation hurts the engine and shortens its lifetime dramatically. It shortens also the maintenance interval and can break the engine completely. The user has full responsibility of the carburettor. The color of spark plug and exhaust are still good ways to understand if you're lean or rich. Engine seizure is always the user's fault. Fuel can have significant amount of dirt in it, so make sure that you always use a fuel filter. Also clean the carburettor filter regularly.
How much is the optimal water temperature?
In a two-stroke engine the optimum water temperature is typically 50-52 Celcius degrees. The optimal temperature depends a bit from the stringency of the engine meaning the gap between cylinder and piston. A loose-fitting engine runs better when it's cool and a new engine can run better when it's hotter. The engine should always be minimum 45 degrees before stressing it to prevent cold-seizures.
How much is the optimal exhaust temperature?
IAME has given information that the optimum EGT is 620 Celsius degrees with a Unipro sensor. This refers to the highest temperature during a lap. When you make the carburation richer by opening the screws, the EGT goes down and vice versa. The L screw affects on the whole area and the H screw affects only on top temperature. The lowest EGT is usually at 430 Celcius degrees. The sensor type, position and the manufacturer can be significantly different, so the numbers aren't always comparable.
Is the X30 carburettor going to change?
Yes. No we're using Tryton carburettors but they will be replaced with Tillotson in 2018 because of varying quality in the previous product. There's going to be a special campaign in winter 2017-2018 when you can purchase a new carburettor with a special price with an engine number. More information is available from each importer. The performance gain is minimal - based on tests, Tillotson has been 0,1 seconds a lap faster. The change is only to improve quality and equality between the engine packages.
How is the engine supposed to be maintained?
We recommend keeping details use log of engines including hours and consumed fuel in litres. The lubricant should always be an option that IAME recommend in the manual to maximize engine lifetime. The engine revs 16000 rpm, so it wears the engine especially on top rpm. Honing the cylinder is a standard procedure when changing a piston, making sure that the cylinder is perfectly round. Honing increases the cylinder size - that's why there are so many different pistons available. When maintaining the engine, it's recommended to follow all instructions and recommendations which you can find also from the top menu: Concept - Engine. It depends fully on the amount of driving but a basic rule is that you need to change the piston to every second race and open the whole engine once a season for full maintenance.
Is there a warranty?
There's no all-inclusive warranty in X30 engines. Obvious manufacturing mistakes such as stator failures have been replaced by warranty by the importer.
What shall I do if my only engine breaks in an event?
You can always rent or borrow an engine from a dealer or a friend. The regulations are designed in a way that you can use freely two engines during an event. It's enough when you deliver the engine number and explain the situation in the scrutineering.
What's the engine selling rule?
Every X30 driver must sell his or her engine with a fixed price to another competitor if there's someone who wants to buy it. The organizer gives a new engine in return from the importer. More detailed information is in the series regulations.
What am I supposed to change in wet conditions?
It's a good habit to have a 10-teeth front sprocket with drum ready for wet racing. By default you use 11-teeth front sprocket in dry unless the track is really a Mickey Mouse version with high kerbs. Changing one tooth in front equals approximately seven teeth in the rear. For instance 11/77 = 10/70. The calculation varies a bit depending on which range you are moving. Changing only the front sprocket is quick and you can always use the same chain. The clutch drum opens nicely with a 17 mm tool when the flywheel is locked. Also in the wet it's recommended to use some rain protector on top of the air filter preventing water from blocking the air intake.
Tires
Why does the organizer deliver the race tires?
The tires are delivered by the organizer because that's the only way to guarantee that all the tires come from the same manufacturing batch. There can be performance differences between different batches. We want to take all possible actions to guarantee equal starting position for racing to everyone. If sometimes it's necessary to use different batches or shipments, at least in every class the situation is identical.
Why is the tire delivery so slow?
As an example, in Lievestuore event, the tires (over 1000 pcs) were delivered within 24 minutes on Saturday morning. From two lines, it's about 20 seconds per participant when the participant chooses tires. The tire barcodes have been registered beforehand to full sets, so we save time by reading only one barcode. In practice, it's not really possible to speed the process up if we want to keep the possibility for participants to choose their own race tires.
Why the organizer doens't give the tires and let's participants choose their tires?
The process was changed in a way that nobody can touch the tires before selecting the sets. The organizer doesn't give the tires because we want to remove the possibility that someone could affect on the process. The participants don't have any chances to study the tires, so it's technically same thing as making a lottery for the tires. In a lottery, the participant has no chance of knowing if all tires are included in the lottery however.
Why the tires aren't sorted by their barcode number?
Tire bar codes are completely random and you can't estimate the manufacturing time or any other features from them. Organizing the number can only have a psychological effect.
Why the tires have been given on Saturday and not on Friday?
Renkaat jaettiin edellisessä kilpailussa lauantaina sekä ylimääräisten sarjojen toimituksen vuoksi rata-alueelle sekä siksi, että se pienentää riskiä merkittävästi renkaiden pehmennyskemikaalien käyttämisestä.
Why the tires aren't shuffled completely before dealing them?
All tires come from the same manufacturing batch and delivery based on information from the importers. Komet: The tires are dealt into boxes based on their circumference because there are minor differences - that's why you can't really completely mix them. In each set the rear tires together and the front tires together come from the same box.
Why the drivers' briefing and tire delivery aren't always on Friday?
Not even nearly all drivers are present at the track on Friday night and we want to keep it possible that you arrive only on Saturday morning. In the long run, it's quite obvious that at some point we need to start having Friday briefings.
Why Komet tires are used in X30 series?
Komet is a tire brand for IAME which is designed specifically for X30 classes regarding performance and durability. The tire is used in all international events and series and in most national championships. In theory it would be possible to use another tire also but it would affect deeply in other things such as prizes of the series.
Who manufactures Komet tires and where?
Italian Vega factory manufactures Komet tires in their Brazilian factory.
Why are the performance differences?
Rubber is a living substance and two tires are never identical. We must always talk about minimizing the differences. The tires aren't perfectly equal even in Formula One with their enormous budgets. Every tire manufacturer has the same challenges and the quality varies from year to another depending on the number of tires manufactured. Komet: If there are 20-25 drivers within 0,2 seconds, it's quite reasonable to say that there can't be huge differences between the sets. When the engines are really equal, other areas are looked more in detail. The tire manufacturing process is also completed after the first session at track. How you stress the tire and cool it down can have a major impact on the tire life and perfomance.
Why are the differences in the hardness of tires?
The hardness of tires can't be measured from a used tire in a reliable way. Even when measuring new tires, there are many things that can affect on the measurement. Some examples are storage history, circumstances, measuring tool and the person taking the measurements. Tires also have other features than hardness. When tested, the tires have always been within the tolerances of the manufacturer.
Why the number of tire sets is limited to one?
There's only one and simple reason: keeping the mandatory cost low. If two sets were allowed, it'd be very few who come to races and actually believe truly in their chances to win the race. Some defend using two sets by saying that anyway you need to buy new tires to practice sessions because the old race tires are so worn out. However buying practice tires is always optional and not really necessary.
Why can't I buy a new tire set if I feel that I've got a bad set?
If we gave a chance to buy a new set of tires after qualifying, it would be unfair to others. The main principle is that everyone is equal. When the tires are given to participants in a fair way, the probability is the same for every driver for every result.
Why old tires are faster than new tires?
The type of tarmac can have a huge impact on the function of tires. On some tracks old tire can be much faster than new tire. Sometimes it can mean problems with the kart chassis settings, like having too much traction. Each chassis type reacts differently to tires. Some are very sensitive to tires and some go always well. Tire pressure may need to be adjusted dramatically. In kart tires are also the suspension of the kart and too low tire pressure can cause bending of the tire itself and depending on kart setup, you can work with very different pressure ranges.
What's a good pressure?
It's recommended to measure and level the pressure especially when the tires are warm right after driving. Usually there's more pressure in the front tires compared with the rear and less on the outside than inside tires. A good basic model is to start from the outside rear tire and add 0,02 bar when moving to the inside rear tire, then to the outside front and inside front. Using this method we reach a scale of, let's say, 0,68-0,74 bar. If the driver is aggressive and slides the rear, lowering the rear pressure relatively can be a good choice. Warm pressure is typically 0,85-0,9 bar. If you burn the tire with too high pressures, the compound may change permanently. If the tarmac is new and smooth, the optimum cold pressure can be over 1 bar also. The pressure in rain tires in heavy rain is 1,5-1,8 bar, in light rain 1,2-1,5 bar and when the track dries, you can go lower than 1 bar.
Do you have a new good question? Please send it by email to: karting(at)radalle.com
