I had a chance to run my new Stage II bike for the first time over the weekend at Sand Mtn. Below is a list of whats on it

Compared to my other Stage I'ish DS this thing defately has longer legs. It will pull all the way up to the RPM limit on the Vortex witout any problems. Bottom and midrange fell about the same as the stage I. On flat ground the Stage II definately feels faster and is much funner to ride with the increased top end.

Here is where I am a little dumbfounded. My stage I with same gearing and paddles will pull the long hills at Sand Mtn in 3rd gear at a about 6500-6800RPM and never feel like I have to downshift into second. The stage II on the other hand I kept having to shift back down into second about 3/4 the way up the hill. I would shift into third gear about a 1/4 way up the hill and where my stage I would pretty much hold the same RPM all the way up, the power would really start falling off on the stage II in a big way.

I am still playing around with the tuning on the Stage II however I don't think it is that far off. I'm not sure at this point if I have a tuning problem or if this is just how these more agressive cams act when they fall out of their power band. I am going to throw a 42 sprocket on the rear next time to see if it helps out.

HR3 cams
HR 14:1 piston w/thicker gaskets (11.5:1 effective compression)
CT full exhaust
Lectron 46HV (K&N - no airbox)
Vortex CDI
Barnett CF clutch
15/40 gearing
8 paddle 22" extreme haulers

 

First reason why this could happen is your jetting could be off( possibly rich) and the longer your mototr is under load the more rapidly you will fall in RPM's.

Second , when running aggressive cams you will need to go up on your compression to make up for the loss of bottom end LOST by the aggressive cams. Also if your a big guy this will be more the case (gravity is a bitch).

The easiest thing to do is like you said , match your gearing to your motor. If it wants to rev, then gear accordingly.



My suggestion would be to go back to 14:1 and ReJett that lectron to Alky. Your quad will run 100 times better.




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Dsengineer, I run that same gearing on my machine, our hill here is comprable to that at sand mountain, and I pull third the entire hill. It does rev up to 8300 through the whoops and falls to 7700 at the top, perfect. If you are falling off, gear that baby down till you ever rev a little in third at the start, she'll pull hard the rest of the way. That 42 might just be the answer. I dont know where the HPR 3 cams power is at, but gear that baby to hold it the longest time possible. Mines actually at about 7800, so I need to gear up a little, but good luck. Jed

 

DSEngineer,

What you are experiencing is actually pretty common when people get an aggressive cam in there and try and dune ride it up a hill. I've done the same exact thing with my EX - I got a very agressive cam, and it simply does not pull like I want it to in the low end. If you ride hills a lot, you might consider a cam that has more low end. Re-gearing will help a little in the short term.

 

I just went to a stage2 with the Woods cams A1/A2 and it is big time difference,I have the RWR 12.5:1 piston.I had a TRX450R with cams,piston full exhaust etc.pull up and wanted to run,it was DS from the get go to the finish on sand.It really feels like it needs another gear, it pulls hard in 5th.I will have to save for the stage2.5 or the stage 3 head now.[img]i/expressions/face-icon-small-happy.gif[/img][img]i/expressions/face-icon-small-smile.gif[/img][img]i/expressions/face-icon-small-wink.gif[/img]

 

When I went from bone stock to the 70hp Genisis kit I had to gear down slightly to take advantage of the new rpm range. With the new gearing my bike came alive and put the new found hp to work. Jed is right, gear it down.

 

put a 14T on the front and tear the mountain a new **** at 7.5K

I understand you staying at 11.5:1, pump gas is just too convenient, especially on trips, and the mileage loss of alky can be a big deterent for a trail/bowl bike.