rev boxes, high rpm's and heat

[acz440ex]

I found myself hitting the rev limiter frequently so I put a Big Gun Rev Box on. I am concerned about a few things and was wondering if anyone has been running this one or a similar one for a long time. Heat is a big concern for me. I have a 440 kit in it and I heard an advanced curve would generate even more heat. I am also concerned about the extra 1000 rpm's. I have stock springs with a Stage 2 cam. I don't want to float a valve or anything like that. I just built it this year. When I hit the rev limiter now it is only in 1st, 2nd, and sometimes 3rd and I'm not even close to running out of power. I want to use all available power but not at the risk of a rebuild. Any help is appreciated.

[krt400ex]

def. get hd valve springs. and u could get air scoops and run race gas to cool it down. if u run race gas make sure u jet accordingly.

[RiderTRX400ex]

damn you run that thing harD! lol well anyways, air scoops, and race gas like krt400ex said will help, you should look into a larger oil cooler or i think its Four Stroke Tech that makes an awesome cooling kit with steel braided lines, but requires a little bit of work.. but is around $120 i think.. maybe look into that..


good luck

[krt400ex]

Originally posted by RiderTRX400ex
damn you run that thing harD! lol well anyways, air scoops, and race gas like krt400ex said will help, you should look into a larger oil cooler or i think its Four Stroke Tech that makes an awesome cooling kit with steel braided lines, but requires a little bit of work.. but is around $120 i think.. maybe look into that..


good luck


ya and i just remembered that um makes a larger oil resvior. it holds like a half a quart more oil. that should help too

[acz440ex]

I thought WOT was the only way to ride!? Just kidding. With a stage 2 Hotcam it's strong mid and very strong high end. I run out of rpm's and it's still pulling hard. In fact, when I hit the limiter, the loss in power nose dives the front end and sends me into the bars because I have Ohlins shocks that 'lift' and 'extend' when I'm WOT so the front end drops significantly and I'm not expecting it. I have air scoops. Race gas is just too expensive. I already have plans to put the external oil cooler from FST on it. Do you guys use an aftermarket rev box?

[GPracer2500]

I use to but the additional ignition advance made my engine more prone to detonation. If I use a race/pump mix I use the box.

[acz440ex]

Originally posted by GPracer2500
I use to but the additional ignition advance made my engine more prone to detonation. If I use a race/pump mix I use the box.
I haven't had mine out yet with the new box but I will watch/listen for detonation. Do you think the extra rpm's will be a problem?

[krt400ex]

Originally posted by acz440ex
I thought WOT was the only way to ride!? Just kidding. With a stage 2 Hotcam it's strong mid and very strong high end. I run out of rpm's and it's still pulling hard. In fact, when I hit the limiter, the loss in power nose dives the front end and sends me into the bars because I have Ohlins shocks that 'lift' and 'extend' when I'm WOT so the front end drops significantly and I'm not expecting it. I have air scoops. Race gas is just too expensive. I already have plans to put the external oil cooler from FST on it. Do you guys use an aftermarket rev box?

not yet:devil:

[krt400ex]

Originally posted by acz440ex
I haven't had mine out yet with the new box but I will watch/listen for detonation. Do you think the extra rpm's will be a problem?

with a stock cam or a cam that adds only bottom and mid power the extra rpms shouldn't be a problem

[pnut420]

With a stage 2 cam you are fine with stock springs. The FST cooler and a pingry oil tank help. I have a 05 yfz now and the Um oil tank didnt seem to help cool the oil any more if any, they are really thick tanks where the pingry has holes to help in cooling. If you want to spend some extra bucks the msd ignition is really good, just put one on my brothers 440 and cant wait to ride it, send multiple sparks down low in the rpm and does a whole lot more than that.