I checked it out Sunday with my trusty Garmin GPS III. The top speed in 5th gear was 74.3 mph on flat pavement. Here's the kicker though, the top speed down a steep hill was only 74.4 mph! It only picked up a tenth of a mph going down hill. That confirmed what I had suspected all along...this thing has some sort of limiting in the top gears! It doesn't come close to pulling out 5th or even 4th gear. 74.4 mph is only 7254 rpm by my calculations. This thing is supposed to turn 9000 rpm. No, I do not think that it's because it doesn't have enough power to turn close to 9000 rpm in 5th. I can FEEL this limiting factor. Another thing that tells me this is the case is that it will only turn 7747 rpm in 4th. Isn't this a bit strange? If it'll turn 7254 rpm in 5th it should max out in 4th. It had the same speed in 4th going up hill, down hill, and on the flats. I didn't try it going uphill in 5th but I bet you it'll be about 74.2 mph. They had to limit 4th too because if they didn't it would run faster in 4th than in 5th. If you were able to turn 9000 rpm in 4th gear you would be going over 79 mph! They geared this thing tall to kill the acceleration for safety reasons and then used other means to limit the extremely high top speed that would have otherwise resulted in doing so.

If we can find how to defeat this rpm limiter we can gear down and have the best of both worlds. Awesome acceleration, trail riding crawling ability, and stellar top speed! If it would turn 9000 rpm in 5th you could still go 85 mph even if you dropped the front sprocket one tooth!

Any mechanics out there? How do we defeat this safety mechanism???

 

Wow, that is weird. What will win in a drag race a DS650 or this new raptor? Which will win?

 

That does sound suspecious about 4th & 5th gear.

 

"What will win in a drag race a DS650 or this new raptor? Which will win?"

I'm not trying to be rude but please, let's not make this into a Raptor v/s anything thread. Let's let this thread be strictly about top speed, gearing, and the affects of changing it.

There are plenty of other threads discussing the Raptor v/s just about every quad ever made so please, humor me.

 

There were magazine reports saying that they never hit the 9000 rpm rev limiter during their rides. And I have not hit it on mine so far. Yet, when I was racing the DS, his cut out at 7200. A more efficient exhaust system may be the answer to getter the higher revs.

 

WSanders

Do you think that when people get the smaller sprockets on there machines that it will still only turn 7700rpm in 4th and 5th??? To me it sounds like it will.... It is good to know that the machine has the power to turn 9000 in 5th.. if it wasn' being limited....

meanwhile still waiting...

 

When you raced the DS, could you run with him on top end?

 

Hmmm...it's just the fact that the thing ran the same speed on flat ground and down hill in 5th that makes me think that it's not a lack of power keeping it from reaching the higher rpms. And it also ran the same speed up hill and down hill in 4th...at a low rpm. If it were power limited it should have picked up rpm going down hill, don't you think?

If there is some sort of high gear governor on this thing I'll eventually find it and kill it. I'll let you know...

 

Does it feel like a rpm limiter is kicking in? Or does it just seem to be all it has?

You can get to 9000 rpm in the other gears?

If it is limiting you in 4th and 5th, but not the other gears, then here are a couple of ways that could be done.

1. Speed limiter.
2. RPM limiter with gear sensor.

It doesn't sound like it is a rpm limiter like on the DS, since it kicks in no matter what gear your in.

If you change out the sprocket, you should be able to tell a little more. If the top speed stays the same, then it is a speed sensor. If the top speed decreases and the rpm's are the same in 4th/5th, then it is a rpm/gear limiter.

Just some thoughts. I am sure someone will figure it out.

 

Oh, of course, it may be that the limit is 9000, but the engine fails to make HP over 7400. Anyone have dyno charts for a raptor?