Clutch engagement RPM on 2021 Cforce 400s

[sunn]

The clutch engagement on my 2021 cforce 400s was approx 2700 RPM, very abrupt/not smooth.   I obtained a "kit" from RNG consisting of a blue painted spring (spring force unknown) with 12 gram weights, as measured on my postal scale.  Installation was easy; 18 mm and 30 mm (not 32 mm as seen on other writings) impact sockets for clutch housing removal.  The resultant clutch engagement was still up to approx 2500 and very abupt/not smooth.

 The original spring was labeled p/n 0951-1021 (specs for spring force 300/1600) with 18 gram weights.

I called RNG who told me the kit should work fine for my ATV, but that wasn't the case as I found.  

The RNG spring was slightly longer than the stock spring, but felt slightly easier at initial downward force but had more resistance than stock as I continued to push down.  RNG would not tell me what the spring force was.

I then tested the clutch with the RNG spring and the OEM 18 gram weights with the resultant engagement RPM of about 2050 RPM, a little smoother engagement but still not good.

I am really struggling to get any answers on the best combination of spring / weights to achieve a smooth engagement of maybe 1800 RPM.  Note; idle RPM is approx. 1600.

I have searched all the forums and cannot find good information, and RNG appears to be not willing to share information.  What gives here?  Anyone with experience to share?

[sunn]

Ok, I have now optimized the CVT clutch engagement and feel on the Force 400 ATV.  I guess this is my week for ATV maintenance, as I had previously described actions for muffler heat mitigation.

My fix was to obtain a part # CVT5 (spring force 200/600) from EPI Performance out of Baxter, MN.  I had personally visited them and described what I was looking for and he provided me this spring.  I wish I had gotten his name and card to personally thank him.  KUDOs for EPI, easy to talk with.

This work is an easy install;  remove CVT cover, impact/ remove  (CW direction) the 18mm long bolt, the remove (CW direction) the 30 mm bolt.  Pull off the clutch and simply replace the spring. While apart, replace wts to your comfort level.  Re-impact all back together ( CCW direction).  I did try different wt sets 12g, 14g, but 18 gram wts proved the best for my liking.

I now have smooth engagement at about 1900 rpm and resultant smooth travel at lower rpm on the road.

I will never buy anything from RNG again as they were useless to want to help me or provide any information.  Their position appeared to be wanting to sell me their "foo foo" parts without any detail.

Aren't there other Force riders out there with similar wants and needs?

[sunn]

I just backed down the weights to 12 grams because I noted a decided hard to shift occurrence when trying to reverse shift on hill.  I gathered that I had achieved a desirable 1800-2000 rpm engagement with the 18 gram wts but obviously too close to idle rpm with some drag on shift at times.

Now engagement rpm is about 2200 and smooth gear shifting so OK.