15 replies to this topic

[addano]

Hi guys/girls
Just did my first ride on my first 850.
Coming of a 800etec í felt the engagement from idle to be super "snappy"
Trying to do techinical stuff , sidehilling at slow speed in hard packed snow was very difficult cause just thinking about throttle would make the sled leap forward.
Something i have to get to grips with or a setup thing?
Still in break in (79%)
Sled is a 2020 Lynx Boondocker RE Short tunnel 154"
Has the ibackshift clutch kit ( loved it on my 800 Lynx) .


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[gulahus]

Is your belt deflection in spec? Too loose belt would cause "bad" engagement.
What ramps you have? With 966 and DJ kit the engagement should be super smooth.

Lähetetty minun Nokia 9 laitteesta Tapatalkilla

[mike0chek]

might just take some getting used, comparing my previous 800 polaris to the 850 (both stock clutch) the 850 engages 10x harder. but after a full season on the 850BC ive adjusted my riding and dont notice it nearly as much

[Dynamo^Joe]

Hi guys/girls
Just did my first ride on my first 850.
Coming of a 800etec í felt the engagement from idle to be super "snappy"
Trying to do techinical stuff , sidehilling at slow speed in hard packed snow was very difficult cause just thinking about throttle would make the sled leap forward.
Something i have to get to grips with or a setup thing?
Still in break in (79%)
Sled is a 2020 Lynx Boondocker RE Short tunnel 154"
Has the ibackshift clutch kit ( loved it on my 800 Lynx) .


Sent from my SM-G950F using Tapatalk

My friend, what you are feeling is "engagement surge" or "jerk", where the clutch feels a sudden powerful upshift and when you let off the throttle, it immediately "lets go".  Press throttle again, even very slowly, the clutch pushes on the belt, the handlebars feel like they "jerk" out of your hand.  When you try to do a wrong-foot-forward on a sidehill, the handlebars feel like they are surging out of your hands and the vehicle speed ends up being too fast to control your one-foot-walking.

 wrongfootforward2.jpg   6.35KB   32 downloads

 

Here is a print screen of a document in my iBackshift clutch kits.  In the kit literature, I provide an installation guide with tips and tricks on what to do with my kits.

One detail is to have correct "tight" belt deflection.

Two is alter the primary spring cover.

 

Re:two) You can perform the same procedure on stock clutching.  The idea of this picture is to illustrate to you, you can change the engagement speed and lower the force of that "surge" or "jerk", lowering it.

 

The alteration, we've been doing since 2017 and hundreds and hundreds of customers have done this to achieve lower engagement and smooth out the "jerking".  jerking.jpg   13.57KB   27 downloads

 

 

 850 kit - pDrive spring cover - change engage speed.jpg   171.69KB   31 downloads

[Dynamo^Joe]

Is your belt deflection in spec? Too loose belt would cause "bad" engagement.
What ramps you have? With 966 and DJ kit the engagement should be super smooth.

Lähetetty minun Nokia 9 laitteesta Tapatalkilla

Yes if the belt deflection is loose, the clutch will want to "surge" in and out of engagement speed.

Did you get to watch the video of how i want belt deflection done?

 

[Dynamo^Joe]

Hi guys/girls
Just did my first ride on my first 850.
Coming of a 800etec í felt the engagement from idle to be super "snappy"
Trying to do techinical stuff , sidehilling at slow speed in hard packed snow was very difficult cause just thinking about throttle would make the sled leap forward.
Something i have to get to grips with or a setup thing?
Still in break in (79%)
Sled is a 2020 Lynx Boondocker RE Short tunnel 154"
Has the ibackshift clutch kit ( loved it on my 800 Lynx) .


Sent from my SM-G950F using Tapatalk

Question - did you get the clutch kit from me directly or from HSK in Norway?

[2stroke800]

Yes if the belt deflection is loose, the clutch will want to "surge" in and out of engagement speed.
Did you get to watch the video of how i want belt deflection done?

Soo obviously this bid is on a xp, i assume this is what you suggest for the 850 also? Being that you are replying to a g4 freeride thread?

[Dynamo^Joe]

Howdy.  It does not matter to me if it was a 1986 Polaris Indy 400.  Im going to set the belt deflection the same way based on the idea that Im looking for "tension" between the two pulleys.  I dont care about belt height.  I want sufficient "tension" between the two pulleys that balance between the belt not burning from the friction on the belt-to-shaft surface and clutch engaging on the belt.  If the tension between the two pulleys are at an amount where the belt seems loose, then when the clutch engages on the belt, it can push the belt up in the sheaves, higher than its lowest ratio (1st gear) and feel "surging" or "jerking" of the belt.

 indy400.jpg   24.27KB   28 downloads

[addano]

Question - did you get the clutch kit from me directly or from HSK in Norway?

Got it directly from you.
Thanks for the help.
The hype is real, customer service like no other.


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[SoloSldr]

I like it when 'Joe School' is in session.

[Dynamo^Joe]

Got it directly from you.
Thanks for the help.
The hype is real, customer service like no other.


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You can email me up to 24mb (twenty four mb) video of what you observe too.  If that spring change is not sufficient, then with a video recording device, take a small vidya of the problem and email it to me. 

I also get customers to sign up for on googledrive and upload large files there (Free).  You email me the link, and i can watch the vidya to help determine what is going on.

thanks

joey
 

[Basketcase889]

I felt the jerkiness in the 850 when I hopped on one for the first time. Coming off a 600etec to the 850 the throttle response was so instant that it felt "jerky" and really surprised me. My very first ride I gave it a blip of throttle, scared myself and unsettled my footing and the engine brake almost put my over the bars. I had only went 5 feet and it was a rental sled in front of a bunch of people. Would have been really embarrassing right after I told them I was a competent rider. 

 

After a bit of time on the sled, you don't even notice the sensitivity until you get on an 800etec and it feels slow and dumbed down.

 

This may be what the OP is referring to. 

[Dynamo^Joe]

My opinion, this "sensitivity" is purely clutch parts; namely the ramps and their inherent start angle.  When i remove the 441 ramps from an 800etec and install my DJ ramps (415/441 blend) the sled will have the same result of the surging off the bottom end.  Then I get rid of the sensitivity with my ramps by going from a 160/xxx primary spring to a 130/xxx primary spring.

 

Ive also made shims to test belt clearance, placing a plastic shim made out of windshield washer jug plastic or blue crazy carpet and put that shim on top of the primary clutch spring cover.  This shim will be in between the spring cover and governor cup.  That shim will push the sheave more closer to the drive belt.  Hahaha....can't use "sun dried" crazy carpet because that plastic was hard and blew into pieces and jammed the clutch.  No damage though, just have to hit the kill switch because the sled keeps on going when the throttle is off. HAHA...i was laffing.

 

I've taken a set of the 966, 965 and 990 ramps and ground a modified tip on them, this lowers the engagement speed a bit, but mostly, loads the bottom end more and completely eliminates that "sensitivity".  I literally breath on the throttle and my sled starts to move like a tundra xtreme.  I can make my own sled crawl at a 1/4 mph.

 

The other detail you can look at is the "belt gap"  Ive seen pDrives with .080 clearance and that extra clearance will make the bottom end surge.  Tighten up the belt gap with some shims to .030~.020 (1/4mm) and that surging is lowered substantially.  With a bigger belt gap, the clutch gets to take "a run" at the drive belt.  When you have closed up the gap, the sheave can't take "a run" at the belt.  Sheave engages the belt right away.

[Radicalrex]

Really glad I was referred to this thread. Looks like I need to contact Joe! I’m sure he has this issue under control! The jerky ness isn’t for me, way to many trees...


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Edited by Radicalrex, 20 July 2020 - 08:02 PM.

[1709]

My opinion, this "sensitivity" is purely clutch parts; namely the ramps and their inherent start angle.  When i remove the 441 ramps from an 800etec and install my DJ ramps (415/441 blend) the sled will have the same result of the surging off the bottom end.  Then I get rid of the sensitivity with my ramps by going from a 160/xxx primary spring to a 130/xxx primary spring.

 

Ive also made shims to test belt clearance, placing a plastic shim made out of windshield washer jug plastic or blue crazy carpet and put that shim on top of the primary clutch spring cover.  This shim will be in between the spring cover and governor cup.  That shim will push the sheave more closer to the drive belt.  Hahaha....can't use "sun dried" crazy carpet because that plastic was hard and blew into pieces and jammed the clutch.  No damage though, just have to hit the kill switch because the sled keeps on going when the throttle is off. HAHA...i was laffing.

 

I've taken a set of the 966, 965 and 990 ramps and ground a modified tip on them, this lowers the engagement speed a bit, but mostly, loads the bottom end more and completely eliminates that "sensitivity".  I literally breath on the throttle and my sled starts to move like a tundra xtreme.  I can make my own sled crawl at a 1/4 mph.

 

The other detail you can look at is the "belt gap"  Ive seen pDrives with .080 clearance and that extra clearance will make the bottom end surge.  Tighten up the belt gap with some shims to .030~.020 (1/4mm) and that surging is lowered substantially.  With a bigger belt gap, the clutch gets to take "a run" at the drive belt.  When you have closed up the gap, the sheave can't take "a run" at the belt.  Sheave engages the belt right away.

Joe, <<<

 

Ive also made shims to test belt clearance, placing a plastic shim made out of windshield washer jug plastic or blue crazy carpet and put that shim on top of the primary clutch spring cover.  This shim will be in between the spring cover and governor cup.  That shim will push the sheave more closer to the drive belt.  Hahaha....can't use "sun dried" crazy carpet because that plastic was hard and blew into pieces and jammed the clutch.  No damage though, just have to hit the kill switch because the sled keeps on going when the throttle is off. HAHA...i was laffing. >>>

is this the same as closing the "Belt gap" ? with spyder shims?       need a pic of  a shim between the spring cover and governor cup.  thanks.