400ex for racing
#12
Your welcome, Karson
#13
Timing keys are not for high compression motors.... It should say that on Sparks site.
If you want to add to the motor, let it breath. Uni filter, 450r carb, powerbomb header and any decent pipe that that will fit the header. BTW do you have HD head studs?
The best mods you can do to get more speed are suspension. The ex rear shock is ok to start with providing you adjust it. Front shocks suck, total junk. Plain old 450r front shocks are a improvement and you can have a shop change the springs and revalve the shocks for your lbs and riding style.
You also want to think about widening the stance. Get a good handle bar, good as in a comfortable height. Also the ex front brakes are weak and fade fast. A set of stainless braided lines really help the front brakes.
If you want to add to the motor, let it breath. Uni filter, 450r carb, powerbomb header and any decent pipe that that will fit the header. BTW do you have HD head studs?
The best mods you can do to get more speed are suspension. The ex rear shock is ok to start with providing you adjust it. Front shocks suck, total junk. Plain old 450r front shocks are a improvement and you can have a shop change the springs and revalve the shocks for your lbs and riding style.
You also want to think about widening the stance. Get a good handle bar, good as in a comfortable height. Also the ex front brakes are weak and fade fast. A set of stainless braided lines really help the front brakes.
#14
Im not trying to argue or anything but its okay to put the timing key on a high compression engine (I am aware that it makes the engine run hotter), my buddy had a 440ex larger oil cooler and shiz ton of peformance mods i dont even think i can list, but he had the timing key install on there about a year ago and she still runs like a beast, and to Dragracer get a cdi box most defiantly because Honda's rev out much quicker than most of the other racing quads out there in the 400 class.
The sparks key advances the timing 6 deg. There is a guy on ebay who makes a timing key that advances the timing 3 deg and it is safe to run with a high comp piston. The 3 deg key wont make the motor generate excessive heat and it gives you better than stock throttle response.
#15
#17
#18
Another cheap mod is chain drive sprocket sizing/gearing. The 1st # is the amount of teeth on the front sprocket. The front sprocket is the quickest and easiest to change(20-30min), as well as being the less expensive one($10-$20). The 2nd # is the amount of teeth on the rear sprocket. Sprockets do not give you HP, instead sprocket sizes determine your final drive ratio, delivering the power to the drive axle(rear axle). For example: a 12/40 combo will launch you off the starting line like a rocket, but you will be limited to 60mph in 5th gear WAO(wide *** open). while a 15/38 combo while launch you off the starting line more like a VW Beetle, but you may be able to approach a top speed of 80mph in 5th gear WAO. ( could take as much as an 1/2 mile ) I have tried every combo possible on my EX, and I have a list of which combo works best with what you will be doing. I see you may be drag racing, will it be a 1/8 or 1/4 mile??? and how big of a flat track will you be on??? What kind of trails do you ride on, flat and smooth, steep and rocky, ect????
#19
I have also done a few low budget EX builds, with good results. I have around $3000 in my current EX including the purchase of the quad. I can't pass a 450r, but they can't get away from me for the most part. Give me a idea of what you will be doing with your 400. Example: 75% steep rocky trails, 15% 1/8 mile drag racing, 10% barrel racing, and I can give you some affordable ideas.
#20
Another cheap mod is chain drive sprocket sizing/gearing. The 1st # is the amount of teeth on the front sprocket. The front sprocket is the quickest and easiest to change(20-30min), as well as being the less expensive one($10-$20). The 2nd # is the amount of teeth on the rear sprocket. Sprockets do not give you HP, instead sprocket sizes determine your final drive ratio, delivering the power to the drive axle(rear axle). For example: a 12/40 combo will launch you off the starting line like a rocket, but you will be limited to 60mph in 5th gear WAO(wide *** open). while a 15/38 combo while launch you off the starting line more like a VW Beetle, but you may be able to approach a top speed of 80mph in 5th gear WAO. ( could take as much as an 1/2 mile ) I have tried every combo possible on my EX, and I have a list of which combo works best with what you will be doing. I see you may be drag racing, will it be a 1/8 or 1/4 mile??? and how big of a flat track will you be on??? What kind of trails do you ride on, flat and smooth, steep and rocky, ect????