I have a 453EX with extensive mods (cam, porting and polishing, WB pipe and CDI, K&N with 170 main and no lid) I run the stock gearing (15/38)mainly but at times I run a 14 tooth in front. I've seen people with 13's too but I haven't been able to find one, where can u get them? Also i would like a 16 tooth, Renthal makes one but will it fit the stock case saver??Some guy claimed to have a 17 but i don't think this is possible with the availible space. On a racing 400EX a guy had 16/36 gearing with a Baldwin case saver, they are 30 bucks but i was hoping the stock one would work. Also the back sproket size doesn't affect gearing near as much as the front sproket, right? Going from a 38-36 would probably gain you a couple mph I think.

 

I got my 13 tooth front sprocket in Oregon, near sandlake dune area. I couldn't find it anywhere else, if you want low gearing get 14/39. Now the biggest size for the front is 16, and I think you have to get a new case saver.

 

i cant reall remeber it but if u drop teeth on the front doesnt that make you lose speed and if u add it on the rear it loses speed??? just wondering, i have an 400EX and want to get some better speed by changing the gearing??? whats good

 

Not to get off the subject, but I was just wondering how powerful is your 453 kit? But, on topic, Rocky Mountain ATV has 16 and 14 tooth sprockets for the 400. Those are the only sizes I have ever seen for it.

 

If you want more top speed, get 16/36 gearing, that will give you awesome top end, but not as quick of acceleration.
If you want quicker acceleration, I would recommend 13/39. It makes it so you can start out in second gear. To give you an idea of how low that is, on my bike I can pull the steepest dunes in 3rd or 4th with 13/39 gears, on my bike with stock gearing I can only pull them in 2nd sometimes 3rd, and that is with no run just a dead stop at the bottom of the dune.

If you don't want to change gearing, get the DMC exhaust system it adds 5 mph to the top speed of your EX.

 

The 453 kit is AWSOME, with 11:1 compression and the 1/4 inch bigger piston it gave it tons of low end torque. A web cam helped a lot too. Now it will EASILY keep the front wheels off the ground in 5th with stock gearing!!! To me there's nothing better than goin by your friends on the road about 60 mph ridin a wheelie as far as they can see!!!!!!

 

yeah Yeah YEah YEAH!!!!!Might have to buy another 400 to modify.Mayby a yellow one.Yeah!! Stiil raisind HaVoK in S.Cent.Pa.

 

Mr Parks, Where do you get your 453 kit??

 

1/4 inch bigger piston? That sounds pretty big. Myabe I just don't know the piston sizes too good. Sounds like a sweet motor. Do you have any pictures of your quad? How does the stock suspension handle it? Or do you have aftermarket?

 

My motor displaces about 453 cc's from an LA Sleeve that is .230 bigger than stock (inside diameter) .230 isn't far from a 1/4 inch (.250) In terms of piston size thats quite a bit. The sleeve is thick and the head still has plenty of room. It never gets hot even on slow difficulkt trails on 90 degree days. It has been very reliable. You can go bigger too. LRD makes a 460 kit and another place makes 480 kits, I think 480 is an extreme that might produce reliability problems.As to the question about suspension, it's all stock!!! I ride trails with buddies and it's suffient. I did however move the front shock mounts out farther to help keep the front wheels and the ground. This is much easier and cheaper than an extended swingarm thats alter handling characteristics. I ride on trails and NOTHING can keep up, trust me. I embarrassed a few mod badshees, 500 crapzilla's, and even a 660 craptor!


My total mods include: Renthal bars, motion pro twist, Nacs PB block off, PRM bumpers and skids, DG nerfs, bandits in front, 22-12-9 Realtors in back(AWSOME TIRES), front end lowered 3 inches,speedometer(84mph now),tach is on order, high performance rotors, WB full exhaust and CDI Box, K&N and outerwear, no airbox lid with 170 main, port and polishing, web cam, hardwelded rockers, 11:1 compression 453 cc piston and LA Sleeve, i'm sure i forgot a lot but you get the idea, i'm very proud considering I AM ONLY 15! and I paid for the quad and mods all alone with no help, I made the money by mowing 25 local lawns for the last three years, it was worth it!!!! I have pictures up soon of my baby!!