July 02 issue of ATV Action (Loren Duncan interview, pg. 88): "...we didn't try to make it rev higher. It doesn't make any power at higher revs, so that just makes it slower...we use the stock CDI. The EX motor is happiest between 4000 and 7500-7800 rpm...".

The point is, you can rev a motor to the moon but if it isn't making horsepower at high rpm, its a lost cause. Look at a Dyno for this engine (see Edelbrock add on pg. 87 for example). Once you start falling off the power curve, you might as well just short shift it and get back into the powerband.

 

I think if you modded the 400 engine for all top end with carbs and cams it might make a big difference, but I guess they're right. I've always short shifted with what little power I have on the 300 compared to the 400 to keep from hitting the limiter. I disconnected mine, so now it doesn't cut out on jumps and hillclimbs.

 

The 300 REALLY is a bike that does best when short shifted. Actually, the 300 and 400 are at their finest when ridden as trail bikes, where keeping in the low to midrange powerband isn't any problem.

 

Yeah these people who rev the 4 strokes to the moom and back don't gain much of anything. Its better to shift early and let the engine pull you up to speed. The only time I worry about floating the valves is when I hit these giant hillclimbs in 2nd pinned.

 

Well I don't rev mine very high eather. So I asked the qustion on this forum "dose the rev kit just give a higher rev cut off or dose it change the tork kirv?" I got little to no responce. So i asked some friends and got diffrant ansors. I rode a 400ex with one on it and it pulled harder threw low to mid than mine. Granted his has more mods than mine but he said the rev kit made the biggesh diffrance. Now my brother has an xr250 in peaces he said he would let me try out the rev box. So I will and let you know what I think.

 

Hey Bermbanger,
You said you disconnected the rev limiter on your 300EX. How did you do that? I have heard of disconnecting the rev limiter for reverse but I wasn't aware that you could do the same for the hi RPM limiter. Thanks for any help!
John

 

This setup disonnects it for everything.First you have to take off the seat. Then look on the right sidecase and there should be two wires coming out of the engine. A white and light green. Follow the white wire up until it comes to a plug in housing. Unplug it and stick another wire in the housing and ground it. The only differenece is the neutral light will stay on in reverse. Let me know if you have any questions.

 

[img]i/expressions/face-icon-small-blush.gif[/img] You just disconnected the reverse indicatior. THIS DOES NOT REMOME THE HIGH REV LIMITER!!!!! To remove your high rev limiter you need to send your black box located on the left side in the front behind your shock to a engine builder to have it removed. I sent mine to Curtis Sparks. He remonve the limiter and advanced the timing. I have had mine done for about 4 years now with no promlems. You only need to do this when you have engine mods done. I would not do this on a stock quad. Also since you took the reverse indicator out go the distance. To the switch that keeps you from starting you quad in gear. Take those two wires and splice them toghter and ground them to your frame. This remomes the reverse rev limiter and lets you start it in gear.

 

KBass i think your a little confused. This setup does disconnect the high end rev limiter. I know because I can give it heck in 1st and it won't cut out now. If you wanna come and ride it then so be it, cuz I know it does I have tested it. My quad will also start in any gear except reverse even without the clutch pulled in cuz I cut the 2 wires going to the clutch lever and connected them. Could you please give me more clear details on how you made yours start in reverse I didn't quite understand that.

 

Those two wires on the sidecase right bottom by the rear break peadal that connect to two plugs. Remove the two plugs and cut the plugs off. Now splice the two wires together and ground them to the frame. This should work. Also if I read your forum correctly we are talking about the same wires, how did you remove your top end rev limiter by grounding you neutral or reverse indicator switch.