Up grades

[Redseal]

need some of your thoughts, what are some of the first up grades you would recommend

[mb1134]

yellow main spring, lighter rollers/sliders, head and cam.

[SYCARMS]

Do you have a 150cc or 250cc, what make and year?

[Redseal]

I have a SunL SLGK-160 and a Kandi GKM 150

[SYCARMS]

Depending on which one you want to upgrade. The Sunl might be the difficult one to do any engine upgrades on since many of their GY6 engines were of the series B and not the common series A used in 95% of the buggies. Not sure what series the 160 is but I believe it is the odd ball GY6. The candy however will take any of the engine up grades available for the GY6 except the later models with internal reverse will not accept the stroked crank but heads, big bore, and cams will work fine in the Kandi.

[Redseal]

On my Kandi the engine serial number is 1P57QML *14100693*
what are some of the easy upgrades that wont cost an arm and a leg

[SYCARMS]

It will depend on what you want to upgrade. The least cost for engine upgrades are to remove the air box if not already done and replace with an open air filter. Several type are available such as the UNI filter which is a foam filter and has to be oiled with a quality filter oil. K&N which is double in price as the UNI and also has to be oiled, R2C filter which does not need oil about as much as a K&N to clean just use 40psi air. Replacing with either of these filters will require a rejet of the carb. Don't waste your money on hotter coils performance CDI's, with your stock engine they are more than efficient. Mods to the CVT, rollers, torque spring, clutch springs adjust shifting of the transmission but will not give you any more power. If power is what you want a performance head ported and polished with a performance cam is in order for a seat of the pants difference. Several things needed to know such as your location, terrain you will be riding, and what about the engine you feel is lacking and want to improve. You can give me a call to discuss. I can give you the best bang for your buck on your budget with quality parts.

[Redseal]

if I change main jets and filter will I need to change cdi and coil to help burn the more fuel that is being put to it?

[SYCARMS]

No, as I said the coil and cdi is more than sufficient for a stock engine. You will not achieve any gains from a coil or cdi until you do major upgrades to the engine. Your current cylinder efficiently rate is currently at appx. 55%. In other words the total cylinder a/f volume is only filled to about 55%. By going to an open filter and rejet you will only increase a/f efficiency to around 60 some %. The stock 15KV coil is more than enough at this rate. The cdi has several functions, first it tells the coil when to fire and for how long. This is called the timing map. The new buggies with DC cdi's the cdi has been mapped for the heavier buggy which will have different timing events(map) as compared to the much lighter scooter. The cdi's on the market are mapped for the much lighter scooter with
exception to the adjustable cdi which are expensive and from my experience due to using an adjustable dash pot for adjustment which loosens up due to vibration after time and will not hold the adjustments. Second is the duration of the spark which is more than efficient for current a/f volume. Third is it controls the max rpm the engine will produce which should be around 7500-7800 rpm. Your engine in stock form quits making power at 7500 rpm so raising the rpm limit is of no help and will only hurt the engine over time due to the over revving. Until you reach a total cylinder a/f volume of 75% or greater the coil and cdi will be of no advantage.

[Redseal]

ok cool thank you for all your help and info, looks like I will start with filter and jets, any good kits out there you know of??

[ShoeBoxLen]

Originally Posted by SYCARMS

No, as I said the coil and cdi is more than sufficient for a stock engine. You will not achieve any gains from a coil or cdi until you do major upgrades to the engine. Your current cylinder efficiently rate is currently at appx. 55%. In other words the total cylinder a/f volume is only filled to about 55%. By going to an open filter and rejet you will only increase a/f efficiency to around 60 some %. The stock 15KV coil is more than enough at this rate. The cdi has several functions, first it tells the coil when to fire and for how long. This is called the timing map. The new buggies with DC cdi's the cdi has been mapped for the heavier buggy which will have different timing events(map) as compared to the much lighter scooter. The cdi's on the market are mapped for the much lighter scooter with
exception to the adjustable cdi which are expensive and from my experience due to using an adjustable dash pot for adjustment which loosens up due to vibration after time and will not hold the adjustments. Second is the duration of the spark which is more than efficient for current a/f volume. Third is it controls the max rpm the engine will produce which should be around 7500-7800 rpm. Your engine in stock form quits making power at 7500 rpm so raising the rpm limit is of no help and will only hurt the engine over time due to the over revving. Until you reach a total cylinder a/f volume of 75% or greater the coil and cdi will be of no advantage.

nice post man very informative.