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sweet. took a few years but better late than never. was wondering if this project got abandoned

nice how much does the little battery weigh your using ?

never knew minkia got his start on HQ. dudes a ebay legend now. what do u sorry sapps have to say for yourself

if it runs good then just ride the dam thing. personally i find a compession gauge mostly useless for any relevant info. u can use it to see if both sides r the same but beyond that i wouldnt lose sleep over it

u talking the 13-18 700 rad? can get factory shit wid spal fan for $240.

In this post I want to discuss three easy ways to improve engine cooling for your dirt bike or ATV and explain why they are effective. As improvements are made to an engine that increase its power, the amount of heat the engine will create will also increase. Effectively removing heat from the engine and cooling it is very important as the power output of the engine goes up. The cooler an engine runs, the more power it can produce. There are three ways that the aftermarket attempts to improve the cooling system of a particular engine. 1. Increase flow through the cooling system. 2. Increase the cooling capacity of the radiators. 3. Increase the pressure of the cooling system. Let's dive in. 1. Increase flow through the cooling system The flow through the cooling system can be increased by installing a water pump impeller designed to increase the flow rate of the coolant. The reason increasing the flow rate of coolant works is because the rate of heat transfer from the engine to the cooling system is directly proportional to the mass flow rate of coolant. This is thermodynamics jargon, but there are two key parts to consider. First, how much coolant is flowing, and second, at what speed the coolant is flowing. The more coolant that flows and the faster it flows will reduce the temperature difference between the point where the coolant enters into the engine and where it exits. This next part is not quite as intuitive. When the temperature difference between the inlet and outlet is reduced, the average coolant temperature is lowered. When the average coolant temperature is lowered the engine will run cooler. This is why fitting a water pump, which increases the flow of coolant through the engine, improves cooling. 2. Increase the cooling capacity of the radiators Radiators consist of a series of tubes and fins which run from the top to the bottom of the radiator. These are often referred to as the radiator’s cores. As coolant enters the radiator it moves through the series of tubes and heat is transferred from the coolant to the fins. Air passes over the fins and heat is transferred from the fins to the air. This transfer of heat from coolant to air is how radiators reduce the temperature of the coolant. Coolant temperatures can be reduced by upgrading radiators in three ways, by increasing the frontal area of the radiators, by making the radiators thicker, or by using materials with better heat transfer properties for the cores. For all practical purposes, increasing the radiators’ frontal area and improving the core materials is rarely a viable option for dirt bike applications. This is because there is little room for the radiators to begin with and they are susceptible to damage, making the use of expensive core materials a risky affair. Unfortunately, both of these options are better improvements to make before resorting to increasing the thickness of the radiators. Increasing the thickness of a radiator is not as efficient of an improvement as increasing the frontal area of the radiator. In order for thicker radiators to cool more effectively than their stock counterparts, airflow past the radiators is key. When the thickness of a radiator is increased, air must travel a greater distance through the radiator before exiting. The speed the air is traveling plays a big role in determining how quickly the air heats up as it moves through the radiator. If the air is not traveling fast enough through the radiator, the air temperature will rise and equal the coolant temperature before reaching the end of the radiator. Once this happens, heat transfer stops and whatever portion of the radiator remains will not help with cooling. In order for a thicker radiator to be effective, air must flow quickly enough through it so that the exiting air temperature is at, or better yet, below the coolant temperature. In conclusion, benefits from adding thicker radiators will be more prominent in applications where speeds are relatively high. Whereas in applications where the bike is hardly moving, improved cooling may not be noticeable. 3. Increase the pressure of the cooling system The last alteration to the cooling system that can be made is to install a high pressure radiator cap. As coolant temperature increases, pressure increases inside the cooling system. The radiator cap is designed to be the pressure release point in the cooling system in the event that too much pressure builds up. This can occur as a result of overheating or a blown head gasket for example. By designing the radiator cap to be the weak link in the system, other parts of the system, such as seals, don’t end up getting damaged from being over pressurized. The radiator cap features a plug and spring on its underside. The spring is designed to compress once a certain pressure is reached, at which point the plug will move upwards and uncover a pressure release hole where excess pressure will be vented. The coolant’s boiling point and ability to conduct heat are necessary factors in understanding why a high pressure radiator cap can help improve engine cooling. Water alone boils at 212°F (100°C) while a 50/50 mix of water and antifreeze boils at 223°F (106.1C). Radiator cap pressure designations are usually advertised in bar, with most stock radiator caps designed to withstand pressures up to 1.1 bar (16psi). The more pressure a fluid is under, the more difficult it becomes for the fluid to vaporize, and the higher its boiling point becomes. When water is under 1.1 bar of pressure, the temperature water will boil at is 260°F (127°C) while a 50/50 antifreeze mix will boil at 271°F (133°C). By installing a radiator cap designed to withstand higher pressures, an additional increase in the coolant’s boiling point will be seen. High pressure caps are usually designed to withstand 1.3 bar (19psi) of pressure. This 0.2 bar (3psi) increase in pressure over the stock system will increase the boiling point of water or antifreeze by 8.7°F (4.83°C). This will then bring the boiling point of pure water or a 50/50 antifreeze mix to approximately 269°F (132°C) and 280°F (138°C) respectively. While this small temperature increase alone won’t do a lot for your engine, coupling a high pressure cap and using coolants with better heat transfer properties can do wonders. Antifreeze (ethylene glycol) alone is not an inherently good conductor of heat. In fact, pure antifreeze conducts heat about half as well as water, while a 50/50 mix of antifreeze and water conducts heat approximately three quarters as efficiently as pure water. This means a cooling system using a 50/50 mix of antifreeze would have to flow faster than a cooling system filled with pure distilled water in order to achieve the same cooling efficiency. What this means for you is significant cooling gains can be made by using distilled water and an additive called “Water Wetter” in place of an antifreeze-water mix. Water Wetter is an additive that improves water’s “wetting” abilities (another whole subject), adds corrosion resistance, and slightly increases the boiling point of water. A high pressure radiator cap in conjunction with distilled water and Water Wetter as the coolant is by far the best route to go for high performance applications where freezing is not an issue. For applications which must still be resistant to freezing, the antifreeze-water ratio can be altered in favor of mixtures incorporating more water than antifreeze so that the cooling efficiency of the mixture is improved. Just bear in mind the freezing point of the mixture as it is thinned with water will be reduced, so you will need to pay close attention to the environment you are operating in so that the coolant is never susceptible to freezing. A frozen coolant system can ruin an engine and makes for a very bad day!

claude your domes looked good from what i seen. if they have effective cooling around the plug they will b even better. i have no doubts the factory impeller should be in the trash bin. maybe theres something better on the market already or you could make one the idea of enter the water at front of the head first ,might sound good but i dont think it would really be any better than how it currently is without cutting and welding and plugging some of the passges to change the routing altogether. becarefull zilla doesnt lead u to a dead end road

jesus christ claude remember zilla is the same clown that brought us failed ti rods and some half ass fuel injection that never worked. you sure u want him on your team???

why keep bugging claude, flopping the inlet/outlet hoses is easy enough if u want to see for yourself what happens. the water scheme in these engines is shit so i dont see why u think something magical will happen by reversing it. water takes the least path of resistamce which is across the top of the head. go ahead flop the hoses dude

im not sure what the row size is but adding more or making the existing ones longer wouldnt be bad but this only works if theres not plastic body panels or frame tubes obstructing it. factory impeller probly doesnt move much water or at a high rate so thats the other area that could probly be greatly improved. maybe one of the after market impellers are worth a crap. reversing the water direction likely would do very little or nothing on these engine. it works on other engines but theyre completely different routing and entry/exit locations

thats false. plenty more ways besides radiator. but bigger radiator is vage term several ways to make a rad bigger, but not have any better cooling

for quit a while its been commom practice to send the water on exhaust side first but im not sure its even worth the hassle on these dinosaurs

no expert here but I don't like seeing cracks. cracks are never good and it sounds like you weren't happy about it and I wouldn't be either. nobody would. doesn't look like a professional job IMO. just a guess but what I think, they welded the pins into the inner webs on the bench. then installed the bearings onto the center pin and tried to push the outer webs onto the inner web assembly. so the full pressing force was on the welds. from what ive seen from some shops is, it appears they assemble the crank fully then weld. with a quality weld I don't think youll need to go fully around the pin. all that does put a ton more heat into the part. you've still got a press fit and then just a couple smaller qaulity beads to reinforce the press fit. besides that, if the shop isn't careful with beads all the way around the pin, a bead that's to high can grind into the side of the bearing when the crank turns

what shock could i use in da back?

its lsr with shaws and their stiff as mofo. maybe with lower pressure they can work but idk. bike is across town in storage so i cant check what i have until next friday. fox dont have shit listed on their site so i thought they dont have sizes i need

did u just call fox and say what length u need and they make the shocks ?

u plan to have it running by spring? ive got mine in a million pieces right now but it mainly just needs cylinder work then i could put it together. only thing im not sure of is how to bench test the trans. i think its a 2-5 nuetral down but its been a while since i looked at it

110 rod would b fine for a while also. imo theres a big difference between being fine and being perfectly reliable for many years. people forget that often times your using larger heavier piston, doubling the power and increasing rpm 2000-3000 more rpm. maybe claude could put the numbers in his nifty FEA program and show how the shorter stockish rods compare to longer beefier stuff even if u could show the shorter ones revs a bit faster, i think its kind of a weak argument in the big picture but thats just me

could a 125mm rod from a common motox engine be used? those r cheap and easy to find

as a general rule your better off with the longer one. it goes back to the friction loss thing between long and short. but for availabilty reasons you may be forced to use the short one, if the long one is rare and hard to find. with the longer one there may also be a small benefit from the lower primary compression ratio depending if u have a rather high ratio now. longer one may also be structurally stronger since longer rods are typically used in larger capacity engines. some of this is speculation as i dont know anything about your engine or 120 rods. i like the idea of the longer one, if for nothing else but the friction standpoint but i know some hard to find rods can be 200-$300 each

pistons look new and could probly be reused if clearances r good. knockoff cyl should b fine. theyre just a bit ruff around the edges. sleeve windows likely dont match very well to the casting windows but that can be fixed with porting tools

those knockoff cylinders are kind of junky . the machining may not be very good and sleeve might not be straight. if u have porting tools u should b able to clean them up and theyll b usable

jfc

backfire is electrical malfunction somewhere. since u swapped coils already i would swap cdi next. flywheel tabs shouldnt be rounded over. either someone set the airgap to close or the crankbearings have alot of slop

i would buy this place for 20pesos and turn it around in a week