Won't Hit Peak RPM *HELP*

[E-Zmoke 4:20]

I am running a 2011 Pro 800 w Power Addiction Head (13.1) + "The Thing" Can
Non Ethanol chip, and run quality premium fuel w no Ethanol. I have great throttle responce, clean and crisp bottom end and midrange but will only pull 7800-7850 RPM at elevation. I ride Revelstoke which is 6000-8000ft I should be able to pull 64g weights with this setup. My sled will not pull the stock 62g weights at elevation. I have tried almost everything I can think of and am now at a loss. Here is a list of what I have checked and changed, if anyone has any other ideas of what to change/check next I would greatly appreciate your imput.

Primary Spring: Changed to SLP Blue Pink
Secondary: Inspected, all good
Belt: Installed new belt, no change
Power Valves: Cleaned, inspected - all good
ECU: Re-Programmed cleared all codes
TPS: Base was @ .717V Dealership changed it to .698V - Idle was @ .91V they changed that to .932V - Result: Change to idle and even better throttle responce, Still won't hit RPM's
Throttle safety switch: Inspected all Good
Throttle free play: Inspected all Good

Would a broken reed petal possibly be the cause of my RPM loss? This was my next thing I was going to check/replace.

Thanks in advance for your imput

 

[IQ?]

Ditch the can......
It will rev with stock exhaust.
ED

 

[slim800]

rpm

I had the same problem with the same head and an HPS can.Believe it or not you need to go to 64gram wieghts and your RPM will run at 8000-8150.I didn't believe it when I was told that, because I have always believed less wieght to get more RPM. Just try it you will like it.It pulls hard all the way.

 

[E-Zmoke 4:20]

I had the same problem with the same head and an HPS can.Believe it or not you need to go to 64gram wieghts and your RPM will run at 8000-8150.I didn't believe it when I was told that, because I have always believed less wieght to get more RPM. Just try it you will like it.It pulls hard all the way.

I have tried it w the 64g weights in. Won't pull past 7850RPM - Their is little change swapping from the 62's to the 64's??

 

[Demo250]

Higher compression heads usually mean lower RPM. I would think you should be pulling 64s at about 8000 RPM though, so I'm not sure. Definitely give it a try without the can and see how it goes.

Edit: Sorry, thought I read you had 13.6 head for some reason. Like F-Bomb said, maybe 64s are a bit too much to hope for.

Edit: Here's a thread with a very similar discussion. That poster found his sled would only reach 8000 RPM no matter what weights he used. 62s would get him to 8000 RPM, but 64s would pull harder and still get to 8000.
http://www.snowestonline.com/forum/showthread.php?t=292217

 

[High Velocity]

Try gearing it down. I am running the same head/can on my '12 Pro, and ride at similar elevations to you. I installed a Camo Peak track and lost 4 mph track speed and 200 rpm. Clutching all stock. Geared it down from the stock 20/42 to 20/46 (74 pitch chain required), and gained 2mph track speed and running 8200 rpm. Still have some clutching to do, but on the right track.

 

[AndrettiDog]

There are a few guys that have said that the HPS can seems to effect peak RPM. I'd try w/o the can too. Go back to stock and take that element out of the equation.

How many miles on the primary? What about the bushings? I had a D7 and the Primary bushings were wearing notches. Replaced those and it came right back to peak RPM's.

 

[stocksucks!!]

ditch the can and add a silber turbo in its place.. no problem hitting rpm now.. not to mention the perma grinn when u blow by all your buddys.imo

 

[turbonium]

my pro

My pro was not getting r's with pa head and stock can.
Bushings on my clutch were shot. Replaced them. Added 300rpm
Dropped from stock 62 gram to 60 gram weights.
Now i get 8-8100 under load in deep.
im at 6-10k feet.
Good luck hope it is something simple.

 

[F-Bomb]

What track?
What RPM will it pull unloaded (like trail)?
Stock secondary setup?
Why SLP primary spring?

Can you see a mark line on your primary to see how far it's climbing? Bet you'll see it's about a long ways from full shift out. 100r's is...you are stuck in third gear!

(with proper clutching) A 13.1 setup on a stock PRO will not pull 64 grams (standard weights) no way no how at 8000ft and probably not even at 6!. Guys the head is worth only a MICRO % of performance on the top end RPM by it's self. Especially the 13.1 domes which is most likely almost negligible for finish RPM at that alt and under load.

Your expectations of performance have been mislead. The PRO with non eth chip in any form 155 or 163 stock track will not pull that clutching (irregardless of the unknown secondary setup) at that altitude.

Really want to know? Put your eth chip plug in and don't change another thing....YOU WILL report back about how you suddenly gained just about 75-100 r's. Thing is your setup sucks and you'll be buying belts and having sub par performance after spending over $800 on aftermarket mods and that is FLAT WRONG.

Answer those few questions so we can verify it's not mechanical and I'll give you an application that will ROCK and you can go get your monies worth.

 

[E-Zmoke 4:20]

What track?
What RPM will it pull unloaded (like trail)?
Stock secondary setup?
Why SLP primary spring?

Can you see a mark line on your primary to see how far it's climbing? Bet you'll see it's about a long ways from full shift out. 100r's is...you are stuck in third gear!

(with proper clutching) A 13.1 setup on a stock PRO will not pull 64 grams (standard weights) no way no how at 8000ft and probably not even at 6!. Guys the head is worth only a MICRO % of performance on the top end RPM by it's self. Especially the 13.1 domes which is most likely almost negligible for finish RPM at that alt and under load.

Your expectations of performance have been mislead. The PRO with non eth chip in any form 155 or 163 stock track will not pull that clutching (irregardless of the unknown secondary setup) at that altitude.

Really want to know? Put your eth chip plug in and don't change another thing....YOU WILL report back about how you suddenly gained just about 75-100 r's. Thing is your setup sucks and you'll be buying belts and having sub par performance after spending over $800 on aftermarket mods and that is
FLAT WRONG.

Answer those few questions so we can verify it's not mechanical and I'll give you an application that will ROCK and you can go get your monies worth.

Yes Stock secondary setup. Stock track, stock gearing. SLP spring was put in as it was recomended to gain a small amount of RPM and Yes I can see the mark on my primary and you are right again, it certainly does feel like it is stuck in 3rd gear!! On the trail It is pretty much 8000-8100

 

[timber_tramp]

Yes Stock secondary setup. Stock track, stock gearing. SLP spring was put in as it was recomended to gain a small amount of RPM and Yes I can see the mark on my primary and you are right again, it certainly does feel like it is stuck in 3rd gear!! On the trail It is pretty much 8000-8100

I ride the same areas and look forward to you figuring out a good set up.
Running 13.1 PA head and SLP can with a trimmed track and carls clutching .
Mine won't pull over 7900 climbingwith the 10-64s.
With bb 62s it will pull 8100 climbing and feels like its stuck in third gear. I'm running a 19tooth gear instead of a 20.

 

[mntmaster]

I'm curious if you have checked to see what the clearance on your primary is between the belt and sheave (clutch face). Mine was almost 55 thousanths out of spec, when I reshimed I went from 79-8000 to 82-8300. I was also getting black streaks on my primary from this.

 

[xmk1080]

I would try the stock can first and if that doesn't solve it gear it down to 19-43, you can use the same chain. Also take some helix angle out of it, sounds like you are slipping the belt it the primary it maybe upshifting to fast. I would take two degrees out of both angles and put the slp helix slim in it and the delron washers. I had the same problem last year! I can pull 8300 rpm on the hill and 8250 on the trail and the clutches are cooler and way more consistant. Going to add some more weight this year, also have the stock primary spring.

 

[F-Bomb]

OK if you see a haze line on the primary as opposed to a marked line with a sharpie you are getting an incredible amount of high RPM slip. Your primary is doing it's job and your secondary is fighting it. It's a miracle that you are not smoking belts right and left. Just another WAG but you don't have very much time on this setup do you?

OK you confirm with your 8100 trail to 7800 loaded pull comments that you have the standard PRO doesn't work very well clutching versus transmission that about 95% of the general public is on. Your current deal is simply that your system will not pull 64 grams. So you have two choices. Start dropping gram weight until it pulls a loaded R at 7950 to 8050. Then you have a sled that will at least be stock performance and most will think it runs good. You'll get an average of about 500-700 miles on a belt compound. It's the standard 8200-8300 trail and then dumps 150 to 200 R's on the load. Feels awesome and you think like the guy posting above that it's a magical deal. Until some smart *** on my setup or it may EVEN be me...comes BLOWING BY YOU only pulling 8050. (did I mention it will look like your in reverse...alright I jest...but you'll be in pudding and it will look like I'm poaching) Also note I'll be on a 1400 mile PLUS belt with NOT A SINGLE AFTERMARKET VENT and with a silly home brewed track mod that has less traction!

Or choice two clutch properly and trim your track.

It feels exactly like Timber_tramp described and it really bothered me initially. Right up until I found out how much faster my sled was when I held the 7950-8050 R's with THIS correct setup. Confirmed with dyno tests by Power Addiction. Measured point A to point B and compared against a like test vehicle it was far superior with this weird feeling setup. Comparing against the same system but throwing much more R's at it and having the settling style clutching. It also became more finicky so that I had to monkey with clutch weights all of the time. Now 64 grams from 4000 to 8000 and with outstanding performance. Also note I'm not an advocate of the gear reduction...stock with a trimmed track is dead on. The only possibility is the 163 with an extra 50 to 75lbs rider. Also note the 13.6 versus the 13.1 can have an affect on the net results. Timber_tramp your setup is best with 62 grams maybe maybe maybe 63 which requires a file job. I'd put the stock gearing back in as well.

Also note and this should be fun...there is a smattering of thoughts that the polaris system dyno's a higher hp/torque at 7950-8050 because it's a cool pipe setup versus actual field runs where a pipe is hot and the stock pipe works better at 8200. That may very well be true except that the factory recommends max at 7950 plus my field testing proved that theory to be ALL WET on stock exhaust. My best guess is most shops can't find ideal clutching with the PRO and it's a better setup to 8300 no load fade to pull 8100-8200 and call it great. Test and you'll find out that is not the case. (the big hidden kicker is the track problem and the stock head at altitude....you may very well have to over rev and fade to R's if you run a stock track and stock head...it doesn't make enough snort to pull the gear ratio. GOOD DAY (i'm all a chuckle because these comments might bring out some experts for me to race)

 

[E-Zmoke 4:20]

Track is a 163"
I am a lightweight rider

F-Bomb: I hear you, and that is all I want is to run consistently and pull hard, I don't want to compensate for nothing. This thing flat out rips, but I feel it has more in it. Changing weights does nothing for me when loaded. I originally stated that I want and should be able to pull heavy weights. Everyones simple answer is "drop weights" No thanks not for me. I will get this thing pulling 64's at optimum power. I had my last sled dialed right in and that thing ran consistantly all day long. You state optimum power curve is 8050. I agree, I am close but not quite their. How do I achieve Optimum HP curve on this setup? Drop gears? Shim? You state my secondary is fighting my primary and this is how it feels, what can I do to fix this? Also I have rode with bone stock 163's that pull consistant 8200RPM and my setup BLOWS them away only pulling 7800? Just to add another curveball I know guys who are running a 3" track w the PA 13.1 head reeds and HPS can who pull 8100 w 64's in but they have geared them down.

 

[E-Zmoke 4:20]

Markings on my primary

 

[skippy]

Markings on my primary

I would definitely start by making sure your primary is clean and that everything is moving/sliding/functioning as it's suppose to. Have you checked your belt to sheave clearance it should be .020 of less. I just checked mine for the first time today and it was about .060 out... Your belt has a pretty nasty green slick look to it.

 

[purepolaris600]

polaris

all you guys throw out all you clutching setups, just listen to F-bomb did everything he recomended to a pro and am blowing other pros out of the water, A++ on the track mod loved it, just so you guys no running the 13.6 head and carls clutching, 62g bb at 8-10 k pulling 8000 all day long. messing around with the aeen pipe and pulling 64g bb at 8-10 still trying to dial the clutching in a little bit. also running stock grearing with all that extra lowend. totaly loving it

 

[F-Bomb]

Thanks for your report. Just like the Red Bull commercial says...WELCOME TO MY WORLD!

track
clutch kit
head with correct compression for the application

3 simple things and about $650 is all it takes. (it's a package so you need to do all of these not one or two)

So if you run up on a stock sounding and looking PRO yet it JUST KILLS yours... the owner has a rye "RACE ME" smile...take a peek at the track...if it's had a haircut that is one of my boys. There is getting to be quite a few out there. While we wait for the experts to reinvent the wheel on the PRO this group is out enjoying!