KDX 220 aftermarket Rads?

Bigger is better??

I have an 04 and I don't know of any being made for the KDX. You can probably adapt some being made for the 4strokes. Why do you feel you need them? I made changes to my 04 which resulted in over heating problems. So if over heating is your problem I may be of some help.

Hot

Jeff Fredette (SP?) will tell you that it will run hot with out the radiator air flow directional vanes. I tried placing the directional vanes ahead of the radiator guards. Didn't work, had to take the guards off. I have a high compression head and I'm forced to use the Evans product. I've purchased a stock head to replace the high compression unit. Using distilled water with your water wetter will cool better than a coolant/water mix, but offers no cold weather protection. Again I don't know of anyone making larger radiators specifically for the KDX. Maybe some of our other readers know of a source. The only other item is to check the radiator cap to see if its lifting at the correct pressure and checking to make sure your timing is set correct. Buying new radiators and making them fit will be quite an investment, but nothing is impossible if you throw enough money at it. From experience the Evans product does not boil as their advertising says.

I've never checked actual operating temperature using the Evans product. When the coolant boils over as we say, what happens is the coolant is heated to the point to where its created enough steam pressure to overcome the sealing spring pressure of the radiator cap. The cap will lift until pressure is reduced to the point it can seal again. So if you're concerned about actual operating temperature and pressure and all other operating factors are OK, no plugged radiator (coolant side and air side), timing is correct as well as the lifting pressure of the radiator cap. Your bigger radiator approach is probably the only answer.

Its odd that the problem is only with the 220, my son's 200 doesn't have this problem under normal operating conditions. I know of an individual who has a 200 that melted and blew out the left radiator vent plug when the radiators became plugged with mud during a race. He finished the race and had no ill mechanical effects on the engine.

Anyone else got any ideas???

I have seen some people anodize thier radiator a flat black, to aid in thermal transfer. You see it some times at the sand dunes. There are a few guys that swear it cools an extra 10-20 degrees

I am not really sure if it is anodizing, but it's just a flat black coaring that's just on the exterior of the radiator.

Thought

Another item that came to mind is in the selection of size for the radiators. If you have to much cooling surface the motor will take a long time to come up to temperature and when you first start riding you could have what is called a cold seizure of the engine. This is when the piston expands faster than the cylinder. It was not uncommon when we were first making the transition from air cooled engines to water cooled. We were use to just starting the bike up and taking off, without any concern to warming up then engine. You may need to install a thermostat to control cylinder temperature.

Read

Go to the internet and read up on your anti freeze. In its pure state it doesn't cool as well as water and it will gel in cold weather. So the more you use, the more problems you can create for yourself.

Try the evans coolant!!!! I run it in my bike and it works great. The coolant make your bike run cooler than normal anti-freeze and has very little pressure. I also run this coolant in my race car and it does keep the temp 20-30 degrees cooler than regular anti-freeze. What do you have to loose (other than to $40.00 for the evans) and will be much cheaper than new rads. FYI. I ride over 2000 km a year and never have had a problem with over heating once i switched to the evans coolant.

Hi I'm just wondering what evans cooling you guys are running? I've seen I think 3 kinds. :cool:

Evans

I didn't do my home work and originally purchased the type that was good up to 400 Deg. F. The only problem is lack of protection at below freezing temperatures. If I remember correctly the type that is good for 375 Deg. F is good to below zero temperatures. Read closely their data sheets on the products. Also you have to purchase a neutralizing product to clean your system of water. Water will make the Evans product gel. So you have to get all the water out of your cooling system. This presents you with a problem if you have a leak. You can't add water out on the trail. No I have never had a boil over problem since converting and I run a modified, high compression head. So if anyone whats to purchase the 400 Deg, product I have some to sell.

NPG+ This stuff will solve all your problems. At its hottest mine will run about 203 degrees.