Need alittle more rpm. Question

[rags319]

Pro has 400 miles on now. I am getting 7900-8050 on the hill alittle more on the flat. I ride at 8600-10000 ft. Is anyone using a ajustable weight and do you like them or has anyone sanded (grind) a 1/2 gram or so off the back of the stock ones. I am running 10-60. I have not tried 10-58 because I think they would be to light. Heard this sled likes the weight.
Also have blk/purple sec spring in.

Thanks for input

 

[IQRIDR]

The SLP MTX weights work great for fine tuning and they have a nice fat heel which gives you more belt squeeze at the start of the shift. They also close the belt-to-sheave clearance into what factory spec is supposed to be. Great bang for the buck.

 

[rags319]

The SLP MTX weights work great for fine tuning and they have a nice fat heel which gives you more belt squeeze at the start of the shift. They also close the belt-to-sheave clearance into what factory spec is supposed to be. Great bang for the buck.

IQ Can you just replace the stock with MTX or does some shiming need to be done. How do they close belt-to shive clearance.

 

[IQRIDR]

You can replace them without shimming on the '11 800 clutches. They are shimmed too wide from the factory, every one I have checked is out of spec. hence the popping sound from the primary on engagement. The MTX weights will shim it right into spec. Look down your primary and see how wide the gap is on both sides of the belt, you can measure it with a feeler gauge before and after I will pretty much gaurantee you are out of spec.

 

[rotax]

hence the popping sound from the primary on engagement.

i notice a noise (clunk/pop) when going from reverse back into forward, and sometimes after heavy braking.
is this the noise your referring to?

 

[AdrenalineAddict]

Rags,
If your consistently turning 7,900+ you may not want to change a thing. That motor doesn't respond to weight change as well as some. A good friend of mine dropped in a set of 10-58's, only gained 50 RPM's and lost a bit of performance. I rode with a Pro who ran 10-58's and a shallower helix than stock with a stiff spring in an effort to get to 8,300 R's, it ran more like a 600 than an 800.

Rotax,
I believe the clunk you're hearing is normal when the moveable sheave on the secondary slides from the reverse notch to the forward position, all Teams with reverse make a clunk.

 

[IQRIDR]

The reverse clunk is the moveable sheave on the secondary engaging/disengaging reverse as stated. But, if you pull your side panel off, and slowly idle your sled up to engagement you will hear the noise and notice the jerking.

I'm sorry but I do not agree with AdrenalineAddict, I think his friend went too shallow with the helix angles (if anything they need steeper than stock angles at anything below 8000 ft). I would clutch the motor to 8250 with a SLP blue/pink or green/pink and the MTX weights and you will see a trackspeed gain in the steep and deep. derlin washers on both sides of your secondary spring, upgrade to a black/purple secondary spring if over 6k elevation, and let it rip. Trust me.

 

[towngrunt]

I am sorry to post poach but have a question for IQRDR. What weight of MTX's do you recommend?

 

[skibreeze]

Rags,
I rode with a Pro who ran 10-58's and a shallower helix than stock with a stiff spring in an effort to get to 8,300 R's, it ran more like a 600 than an 800.

I'm sorry but I do not agree with AdrenalineAddict, I think his friend went too shallow with the helix angles (if anything they need steeper than stock angles at anything below 8000 ft). I would clutch the motor to 8250 with a SLP blue/pink or green/pink and the MTX weights and you will see a trackspeed gain in the steep and deep. derlin washers on both sides of your secondary spring, upgrade to a black/purple secondary spring if over 6k elevation, and let it rip. Trust me.

IQRIDR, reread AA's post. He said that a shallow helix sucks.

 

[AdrenalineAddict]

Rags,
If you see a performance gain, let us know. I'm going to be riding a Pro next year myself and am always looking for gains. If you have a buddy with a similar sled, have him leave his alone as a benchmark so you have a reference to compare with. Sometimes the butt dyno lies and the extra R's and sound can make you think you've made an improvement when you may being going backwards. Keep us informed, I've had a few tell me the R's work. I've also had a few show me the extra R's don't. The dyno sheets show a flat sweet spot from 7850 to 8200. IQRIDR may be on to something, let us know.

 

[goforbroke]

On an effort to get more rpm, I put in mtx 62,equivalent to Polaris 58's. Had great rpm and performed well. Rode with a friend that had 60's and he only hit 8000 rpm, but performance was better in the deep or steep. I promptly put back in my 60's and only pull 8050 rpm,but on the hill performance is better. We ride 9-10k and Black purple secondary spring. Next year i'll change primary spring to get more rpm, bit not until I have a sled to compare with

 

[F-Bomb]

it's been hit but I'll reiterate...rags if your sled will be consistent and hold that 8050 you'll find out when comparing the setup to a like sled that you will be making faster ground speed if your sled is maintaining that level at full shift. 400 miles (assumpted on a single belt) and a good consistent 8050 on a loaded climb and 8100-8150 on packed is EXCELLENT CLUTCHING. No excessive heat and thus fade after multiple climbs or 15 minutes of hard varying rpm boondocking? Leave it alone you're there.

The stock polaris exhaust/gearing/port timing/spark combo is designed to operate at that RPM. You can vary how you get there with helix/springs/weight profiles and accomplish a quicker sled or one that takes advantage performance wise of the conditions you most enjoy....but making more R's is not making more power unless you change your exhaust/spark/port timing/ ect ect.

 

[rags319]

Thanks F-BOMB

Thats what I wanted to know. Think I will leave it alone then.