Where do you start with performance mini moto parts
Ok, so starting with the larger more expensive parts, as these are likely to give you the biggest power increase. I would recommend boring your engine out and port and polishing your head. This will vastly improve the performance on your mini moto and straight away you will notice great increase in power throughout the rev range. Now is a great time to buy these kits as they have come down significantly in price, I have seen these kits for as little as 15. I wouldn't jump into buying a really cheap one though. It might be worth investing a little bit more as this is a large part of your engine which you are playing with.
After you have fitted this kit, There are a couple more large modifications which could be done to your mini moto. Firstly I would replace the carburettor and air intake system. Performance, bored out carburettors increase air and fuel flow through the bike and the main principal with any engine is more fuel + more air = more BHP. Although the carb will need tuning to get it running right and to the best of its ability it is a worth while process. Once you have a carb it is essential you also buy a performance air filter (K&N style) as well as some carbon race reeds and larger jets to ensure that this part of the bike is as unrestricted as possible. If you add this modification alone it will make a slight difference but the engine is still heavily restricted.
This restriction is mainly in the form of the exhaust. Mini moto exhausts often do not allow the engine to perform to its full capabilities, for that you need a performance exhaust with a good expansion chamber. This will help the bike to perform at its best. This combined with a performance carb and air filter etc. will make the bike feel completely different. It will rev more freely, pick up pace a lot faster and hit a higher top speed. With all these mods combined your bike will accelerate far quicker than before and hit anything up to 15-20mph more in some cases.
Some smaller, but very important modifications which I would now carry out would be to the clutch. The clutches found on most standard mini motos are often very weak with weak springs. This will hinder your bikes performance and also these clutches will wear down very quickly. Especially with the extra power. Invest in a performance clutch and clutch springs and you will see better, smoother acceleration as well as better pulling off the line. Clutches can be found very cheap but are a worthwhile investment.
I would also invest in a rocket key. These help the engine timings and again will ensure smoother, faster acceleration as well as better pace off the line. These are probably one of the cheapest performance parts you can buy for your mini moto, I have seen these for sale for around a fiver, well worth the money.
With all this extra power the engine needs to be able to cope with it, especially the ignition system. I would recommend upgrading the spark plug, spark plug cap, lead and coil in order to make sure your mini moto performs as it should all the time. Standard ignition systems will struggle to cope with this extra power and will often burnout or break which could result in a blown engine so I feel it is vital to change these parts. The best parts for me would be the NGK range. They have proven reliable and when using them on mini motos, the bike feels like it is constantly performing at its best.
Another problem with mini motos is the standard chains which you get on many bikes. They are very weak and will break at the first sign of extra power. I would upgrade to a heavy duty chain to ensure it doesn't snap when your racing, not only will it cost you the race, but could also cause injury and damage to your engine.
Now, many people ask how to change the gearing of their mini moto, to prepare it for different tracks. The answer is simple, change the sprockets for different sized sprockets. The general rule of thumb is larger sprockets mean slower acceleration but a better top speed. This kind of gearing will be used on tracks which have large straights and less bends.
Or, you could use smaller sprockets, which mean faster acceleration but a lower op end speed. This kind of gearing will be used on twisty tracks where you may not have the chance to top your mini moto out.
Hopefully this has started to help you when modifying your mini moto for performance, just remember that whatever you do, stay safe and enjoy yourself.