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Discussion Starter #121 (Edited)
Ok I got a little data for you guys....
Tested with 18g weights, 36g wet slugs, Exh Tip, EPI Gold Spring, Pitbull Growlers 27.1” = 66lbs overstock tire weight and 1.5" taller over stock tires, Tire's set at 6 PSI, EHS tuner set to tip settings plus .5 in the green mode = 4.5

All test are on a nice paved road.

10 MPH - 3480 - 3500 RPM's
20 MPH - 4190 - 4200 RPM's
30 MPH - 4890 - 4900 RPM's
40 MPH - 5480 - 5500 RPM's
50 MPH - 6050 - 6100 RPM's

GPS Performance Meter testing showed (Average of 2 runs)

0 to 60ft —- 2.23 sec @ 29.0 MPH
0 to 300ft —- 6.78 sec @ 48.5 MPH
0 to 500ft —- 9.03 sec @ 53.8 MPH
0 to 660ft — 11.00 sec @ 56.7 MPH
0 to 1000ft - 14.94 sec @ 60 MPH
0 to 60 MPH 928ft & 14.13 Sec
Top Speed of 61.2 MPH

So I lost about 2MPH with shim & EPI gold spring & the new tires. As you can see in the data I gained nothing from 928ft to a 1000ft for MPH & RPM's are up everywhere. So that is telling me the gold spring is holding it back to far but it seemed lazy and I had to add a lot of extra throttle with the purple spring. This past weekend I add'ed a 1/2 point to my green mode on my fuel controller and it seemed to pick up a lot. I also checked my gas mileage this weekend after adding a 1/2 point to the green mode and it was down some right at 20MPG.

This Data is from Post #1 when it was stock with no wet slugs or secondary springs with stock tires. So actually the Rpm's is very close to stock.

10 MPH = 3250 - 3280 Rpm's
20 MPH = 4150 - 4180 Rpm's
30 MPH = 4730 - 4750 Rpm's
40 MPH = 5380 - 5410 Rpm's
50 MPH = 6010 - 6040 Rpm's

And this Data is from post #9
Run #1
0-60ft ---------- 2.14 Sec @ 30.2 MPH
0-300ft ------- 6.53 Sec @ 50.0 MPH
0-500ft ------- 8.75 Sec @ 53.7 MPH
0-660ft -------- 10.73 Sec @ 56.9 MPH (1/8 Mile)
0-1000ft -------14.76 Sec @ 57.6 MPH
0-1320ft -------18.33 Sec @ 60.2 MPH (1/4 Mile)

Run #2
0-60ft --------- 2.11 Sec @ 29.9 MPH
0-300ft ------- 6.49 Sec @ 49.8 MPH
0-500ft ------- 8.70 Sec @ 54.7 MPH
0-660ft -------10.65 Sec @ 57.3 MPH (1/8 Mile)
0-1000ft ----- 14.57 Sec @ 60.0 MPH
0-1320ft ----- 18.13 Sec @ 61.5 MPH (1/4 Mile)
Top Speed 63.1 MPH (Note. I did not hold it WOT as long to get a full top end run today but its still with in 1.1 MPH so close enough.)
0 to 60MPH time and distance. 13.05 Sec and 865ft.
 
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Discussion Starter #122 (Edited)
I am kinda surprised I lost a little ET in 60ft as the front end hiked up about 8-10" for 4-6ft or so which it never has stayed up that long before. Usually it lifts it and sets it back down in a foot. At this point I am thinking about going back to the heavier weights just to try it and if I still can't get what I am looking for I am going to pull the wet slugs out at my next oil change. I will admit its snappy at trail speeds with the gold spring in and I like that part of it. Maybe the combo of the gold spring and heavier weights will work out??
 
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I am kinda surprised I lost a little ET in 60ft as the front end hiked up about 8-10" for 4-6ft or so which it never has stayed up that long before. Usually it lifts it and sets it back down in a foot. At this point I am thinking about going back to the heavier weights just to try it and if I still can't get what I am looking for or I am going to pull the wet slugs out at my next oil change. I will admit its snappy at trail speeds with the gold spring in and I like that part of it. Maybe the combo of the gold spring and heavier weights will work out??
Awesome data! Thanks sooo much for updating your thread with fresh info.
 
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The higher the tires rise, the less forward bite. The increase in radius of the distance traveled by the front tires for any distance increases the time required to cover that distance. That's why drag racers try to travel a straight line from the start timing trap to the finish line timing trap....and keep the front wheels close to the ground.
 
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Discussion Starter #126 (Edited)
@Zrt1200

So you lost a full second in your 0-60 MPH from stock to current set up correct?
Yes. If you compare the data It starts losing at the hit of the throttle. I am really starting to think heavier weights and cam plate mod for one last chance with these wet slugs. I was looking over at Airdam clutchs and reading a little about those guys not that I am having them do any work but he is talking about lightening the clutchs and cam plate mod. IMO adding wet slugs is like having heavier clutch weights as its a extra 36g of rotating weight. So in theory if you took 36g off the sheave you would be comparing apples to apples. But with the wet slugs the wet clutch is locking up earlier causing a acceleration issue to begin with as it cant get up to the Rpm's it's designed for at take off.

Drag racers remove every gram of rotating weight as possible. On snowmobiles with a track that turns hard. 1lb of rotating weight equals 7lbs of dead weight for acceleration.
 
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:)
The slugs have no relationship to the primary weights. The primary weights do not care if there are slugs installed or not. I bet with the right equipment I could confirm the percentage relationship of slugs to changed engine r.p.m. when the shoes engage.
These were first used by mud riders to help keep the wet clutch fully engaged at low engine r.p.m. and to add length of life to the shoes.
I think if you use slugs you should then have new shoe springs, springs engineered with more tension,the same percentage spring tension increase as the percentage increase in the total weight of the shoes with the slugs. That would let the shoes with slugs engage more firmly, much closer to the stock shoe engine r.p.m. engineered.
Another thing that happened years ago here at G.C. was members "thinking" reduced rotating mass would help the griz off the line. They tried grease less weights to remove the grease cover and grease and I don't remember more positive reports than negative about performance differences.
 

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You saw a similar lose in the post.

Installing slugs and stall spring together would be counter productive.
Actually mud riders used stall springs to jack the rpms into the powerband before engaging hitting the mud with the most torque the Grizz could muster. This is similar to snowmobile modders striving to keep the rpms in the power band at nearly all speeds.
Slugs are more for slower trail riding. To help prevent burning the WC blocks.

There are a couple primary machiners that purposely reduce the primary weight after altering the ratio.
 

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Discussion Starter #129
:)
The slugs have no relationship to the primary weights. The primary weights do not care if there are slugs installed or not. I bet with the right equipment I could confirm the percentage relationship of slugs to changed engine r.p.m. when the shoes engage.
These were first used by mud riders to help keep the wet clutch fully engaged at low engine r.p.m. and to add length of life to the shoes.
I think if you use slugs you should then have new shoe springs, springs engineered with more tension,the same percentage spring tension increase as the percentage increase in the total weight of the shoes with the slugs. That would let the shoes with slugs engage more firmly, much closer to the stock shoe engine r.p.m. engineered.
Another thing that happened years ago here at G.C. was members "thinking" reduced rotating mass would help the griz off the line. They tried grease less weights to remove the grease cover and grease and I don't remember more positive reports than negative about performance differences.
I understand the slugs have no relationship to the primary weights. What I was saying is its a extra 36g of total rotating weight and its engaging at to low of a RPM causing other issues like the wet clutch locking up at to low of a rpm to maximize engine torque.


You saw a similar lose in the post.

Installing slugs and stall spring together would be counter productive.
Actually mud riders used stall springs to jack the rpms into the powerband before engaging hitting the mud with the most torque the Grizz could muster. This is similar to snowmobile modders striving to keep the rpms in the power band at nearly all speeds.
Slugs are more for slower trail riding. To help prevent burning the WC blocks.

There are a couple primary machiners that purposely reduce the primary weight after altering the ratio.
I agree the wet slugs are great for going 5-12 mph all day on tight trails and for heavy work like pulling, plowing snow, etc. I originally put them in as I was planning on plowing snow with my Grizzly then bought a tractor to take care of that problem.
 
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I Put a EPI purple spring in today and went for a 8 mile ride. I was not impressed, it really doesn’t feel much different than the stock spring. It is more noticeable in Low or reverse but in high gear only slightly different, in some areas it felt no different. Kinda disappointed, was expecting more of a change. My CVT ratio is 2.75:1 this is what I had before the spring change and after. Does this sound right?
 

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I Put a EPI purple spring in today and went for a 8 mile ride. I was not impressed, it really doesn’t feel much different than the stock spring. It is more noticeable in Low or reverse but in high gear only slightly different, in some areas it felt no different. Kinda disappointed, was expecting more of a change. My CVT ratio is 2.75:1 this is what I had before the spring change and after. Does this sound right?
Your findings/felt performance are spot on, as the purple spring is not much tighter than the stock spring, which is damn near the same as the orange spring. You should have felt more back-shift than anything.
As for the ratio, that is exactly what you should have determined, no difference from a few pounds of added tension in the secondary sheaves.
The spring is to prevent belt slip as the ratio is raised above stock and also adds back-shift force.
You will like the spring more if you add a machined sheave for a higher pulley ratio and more low end pull off the line.
 
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My CVT ratio is 2.75:1 this is what I had before the spring change and after. Does this sound right?
2.75:1 ratio is basically what my observations were on my bike with 1.5 mm of shims. So nothing wrong with that.

I'm currently at 3.1:1 fwiw
 

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Ok thanks Rigeway & Vincent, good to know I’m getting what I should then.
 

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Discussion Starter #134 (Edited)
I Put a EPI purple spring in today and went for a 8 mile ride. I was not impressed, it really doesn’t feel much different than the stock spring. It is more noticeable in Low or reverse but in high gear only slightly different, in some areas it felt no different. Kinda disappointed, was expecting more of a change. My CVT ratio is 2.75:1 this is what I had before the spring change and after. Does this sound right?
Your 2.75 to 1 ratio sounds about right with 1.5mm of shims. As for the spring I noticed a difference right off the bat with the purple spring but springs varies + or - 10%. So if your stock spring was +10% and your purple was - 10% I would say you wouldn't feel any difference. As a snowmobile drag racer I have a spring checking gauge and you can't believe how far off some springs are. I have seen spring off by 70lbs. That is why I ended up with a spring checking gauge. How do you tune a clutch not knowing what you are putting in there. When buying springs if you don't have a spring checking gauge ask to have them check it before shipping. I have a buddy who buys a lot of springs and he has EPI & Wahl Bros check his springs before shipping them to him. He says a lot of times they have to check 3-7 springs before they get one that is close to what is being advertised.

In the two pics. 1 pic shows my spring checker, the second pic shows the poundage of two grizzly 700 springs and the epi gold spring.
 

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Thanks. Good information. Wish I’d known that before I ordered.
 

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Discussion Starter #136
Thanks. Good information. Wish I’d known that before I ordered.
Call them up and tell them I can feel No difference with this spring over my stock spring. Tell them I am sending it back and you want them to check it because I think I got a bad spring. If it's not close to advertised spec to send me a different one. At least this way you will no you bought a good EPI spring or not. If its good you will know your stock spring is on the plus side of specs.
 

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Ok thanks Rigeway & Vincent, good to know I’m getting what I should then.
My experience with Epi spring was the opposite from you. When I upgraded from my stock 550 /660 spring to the Epi Orange I gain HUGE backshift and low grunt gains! But the problem became the spring was sooo strong the bike reved much more during cruising witch became annoying very quickly. Ended up switching out my stock 16 gram weights for the heavier 18 gram 660 weights witch is the combo I've happily enjoyed for over 5000+ miles
 

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My experience with Epi spring was the opposite from you. When I upgraded from my stock 550 /660 spring to the Epi Orange I gain HUGE backshift and low grunt gains! But the problem became the spring was sooo strong the bike reved much more during cruising witch became annoying very quickly. Ended up switching out my stock 16 gram weights for the heavier 18 gram 660 weights witch is the combo I've happily enjoyed for over 5000+ miles
This is a good thread and we are comparing different machines so other readers in the future need to pay attention to the signatures listing poster's machines.
 
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Call them up and tell them I can feel No difference with this spring over my stock spring. Tell them I am sending it back and you want them to check it because I think I got a bad spring. If it's not close to advertised spec to send me a different one. At least this way you will no you bought a good EPI spring or not. If its good you will know your stock spring is on the plus side of specs.
The response I got back from EPI was that they want to sell me a clutch kit in order for me to get the results I want. I'm not going that route.
 

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Discussion Starter #140
The response I got back from EPI was that they want to sell me a clutch kit in order for me to get the results I want. I'm not going that route.
They wont check the spring poundage if you sent it back??
 
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