Need a little help fine tuning

[ogrant]

Well from what I have read so far this is a great site, so much info. Been lurking for awhile.

I have a 2016 pro s 800 switchback, all stock with the cobra track.

I just want to fine tune what I feel is a bit of a flat spot around 80mph to, around 96mph. It seems to go like a bastard up until 80 then it seems like it's not pulling like it should for a 800 between 80-96.

It will rev usually to 8200-8300 and sit there while doing this so I am not getting any rpm loss.

I have checked my belt deflection, belt clearance, track tension and all seems like the tips that I have seen here on this site. It has the 22/37 1.68 gears in it and all stock clutching. The only mod I have done is getting the primary balanced(no vibrations now).

Now I could care less about top speed, my buddy with his modded turbo cat can own the lake for all I care, I just like trail riding, corner to corner pick up and go. But when I hit the fields in between the bush trails I want to let'r go and feel that it is working right.

I didn't know if I should throw a little weight at it with a new primary spring. I have searched around the site, but the info is just a bit scattered. I know it's here, I'm just having a hard time putting it all together for my issue...if it is even an issue at all.

 

[Powaton]

I have the exact question and feelings as you. I hope more people chime in. But I will also let you know what im going to try.

If I top out at 96 or 104 I don't care right now. Maybe I will later , but now I want the sled to wow me with snap and "ready when I need it" performance. Like my 600 but more.

I'm doing this from my phone. So excuse the sloppy formatting.

I weigh 220 w/gear

Gearing. There is a reasonable consensus that this sled is geared too tall. Clutching can help. But gearing and clutching are the best answer. Because the tall hearing will work against even the best clutching. Brock has written about this. He also explains how the new clutch face angles make things worse for tall gearing.

GEARS
I'm going with 1.74 gearing (40 tooth bottom gear, stock 23 tooth top gear and a 70 pitch chain). It has been said that this is an efficient combo due to friendly chain radius, dog leg etc. I got everything off ebay. This sled has 3/4" hyvo gears/chain. You need the longer chain with this combo. Stock is 68 pitch.

With the lower gear ratio, now re clutch to take advantage of the new gearing and keep RPMs correct.

Weights, springs, helix.

For now I'm keeping the stock helix. I have seen many recomendations and I don't have 300 bucks on hand to play with different helixes. I'll deal with weights and springs, then see if I still feel the need for a helix. The stock helix can work okay.

PRIMARY CLUTCH
White 120/310 Primary spring.
EPI 72 gram Belly Buster weights.

Polaris standard #10 profile weights are good too. Brock and others have mentioned liking the belly buster profile and the fact that they are hard all the way thru. The belly busters are also reasonably priced.

Generally, more weight the lighter you are. Less weight the heavier and/or more track and stud load.

The range appears to be 68-74 grams.

Like, a 220 pound guy with a 1/4" ripsaw studded and 1.74 gearing will likely be in the 70 gram weight range. A 260 pound guy maybe 68, a 170 pound guy, maybe 74.

I got 72 gram weights and will grind some off the back of I need them lighter.

SECONARY CLUTCH
I'm going to try the 155/122 spring. Its a bit beefy but will work with stock helix.

If I try another helix later, I'll go with one of the helix spring combos talked about on this site. As of now I'm still learning. I don't fully understand the nomenclature for these helixes and which ones are "full progressive" "dual angle" or straight and why so many numbers identify them. It looks like they have 4 angles and some have a decimal and a dash. Then people in the know use shorthand to identify them and I just want a drink!

"Get youself a 44 fully progressive" says one guy. Then you read in a post that he loves his 66 44/46.6. Is that the 44?Then another post says 55/44 Then helixes on ebay say "66-56ER 64-54 ER". Is that 4 angles? Two helixes for the price of 1? Where do I buy the 55 and why do I feel stupid? Drinking too much?

 

[ogrant]

good post Powaton..I will be watching this post closely

 

[ogrant]

I thought that I should mention that I am using the pro-x rear spring and pro x FTS spring with valving from Dean at Peak Velocity due to being around 220LBS with gear.

 

[Powaton]

I thought that I should mention that I am using the pro-x rear spring and pro x FTS spring with valving from Dean at Peak Velocity due to being around 220LBS with gear.

I'm doing something similar. 150 rear spring, hygear dual rate center, beefy bottom bumpers and revalve myself. In most cases I'm willing to give up some speed for the ride/handling compromise I like. The trails get so darn rough and I like to jump off stuff. If I ever want to play with speed setups I figure I can use straps and pull things down.

 

[ZR SLEDHEAD]

I thought that I should mention that I am using the pro-x rear spring and pro x FTS spring with valving from Dean at Peak Velocity due to being around 220LBS with gear.

Have you ridden with the spring / valving combo? Dean is certainly one of the best.

 

[racerdave]

Pow, maybe this will help. 66/46.36 is a 2 angle helix. The .36 tells you the 66 angle is .360 long. The 46 is the angle the rest of the way. The .36 is often a .46 which is then .460 long on the top number. 66-46f er is a full progressive helix. It starts at 66 on the top and ends at 46 on the bottom. The angle drops constantly from top to bottom. The er means electronic reverse. A straight helix will have one number only 56 44 etc. No .xx
Regardless of what angles you want to run/try you need a er helix or you won't have reverse.

The numbers I used are all just examples as there are many combinations etc.

 

[Powaton]

Thank you Dave.

 

[ogrant]

Have you ridden with the spring / valving combo? Dean is certainly one of the best.

Yes i have and it is a noticeable improvement over stock. the springs are taking a bit of time to get them set but i think that I am close now. I had a hard time last year getting that rocking point for leaning forward for bite and moving back for traction. I'm running my clickers around 5 for the trails around here and it just skips across the tops of the chop now. Dean did my prox for years and it was much better than stock.

....now about that flat spot around 80mph....

 

[Dr.Notadoo]

great all round helix is the 48-44 full.You can use the stock rear spring, works great..I wouldent put any more spring tension on the stock helix, its very mild and if you make the shift slower the sled will rev and not pull..

 

[Powaton]

great all round helix is the 48-44 full.You can use the stock rear spring, works great..I wouldent put any more spring tension on the stock helix, its very mild and if you make the shift slower the sled will rev and not pull..

Won't more weight in the primary fix that?

 

[Dr.Notadoo]

Fix what? Making the front clutch fight the rear clutch because there's too much spring tension?you need to be able to load the motor if you stiff in your springs you're slowing the shift down not loading the motor your performance will suffer

 

[Powaton]

Fix what? Making the front clutch fight the rear clutch because there's too much spring tension?you need to be able to load the motor if you stiff in your springs you're slowing the shift down not loading the motor your performance will suffer

The combo I described has worked well for many and is used by people whose opinions I respect. We'll see if it works for me too! If it doesn't I'll try other stuff.

If you are willing to share a combo you like, I'll be willing to try that.

 

[Dr.Notadoo]

Ok let's start from the beginning: what exactly is ur set up? And we can go from there..

 

[ogrant]

Ok let's start from the beginning: what exactly is ur set up? And we can go from there..

stock 800 sb balanced primary, i'm 220LBS with gear. deflection good, belt clearance around .010", clutches lined up and track tension around 1/2" at 16" before axel. read first post for the rest

 

[Dr.Notadoo]

Yup I read it before, change the rear helix, there is no midrange load in the stock helix, this will help you pulling issue. Like I said before 48-44 full , leave the stock spring. If you want more go into the primary with more weight and change the spring.

 

[ogrant]

Yup I read it before, change the rear helix, there is no midrange load in the stock helix, this will help you pulling issue. Like I said before 48-44 full , leave the stock spring. If you want more go into the primary with more weight and change the spring.

would that be similar as the 50-44f that Brock talks about? I'm having a hard time finding someone here in ontario that has them in stock. Always have to wait weeks it seems to get them. I guess I can order one from the states...any suggestions?

 

[Dr.Notadoo]

Yes but the start is 2 degs steeper, with a 6 degs spread, instead of 4. Been using both of these helixs since the Axys came out in 2015..

 

[stroker2]

A great source for any angle TSS-04 or Tied helix is SSI -BD EXtreme, they custom cut in house with fast delivery times. Give Erich a call.

 

[Powaton]

Don't underestimate the importance of gearing lower. On this site, read all that Brock has to say on the topic. The theory behind why is sound and in field testing by him and others is positive. "North Star Rick" on Hard Core Sledder and others too.

Plus. Lower gearing will help as conditions deteriorate (warm thick snow) and if your belt/ clutches arn't perfect.

Yeah. A starting point of a perfect belt and perfect clutches is always best. But come February, you may want to ride more than wrench. Lower gearing is more tolerant of all setups.