Helix Question, with description of problem

[Boston Racing]

I have a 660 rmk / 155 with a 62-38.36 Helix in it that Carls sold me. What is happening is on a long pull or in deep powder the sled will not hold rpms once I loose track speed. If I start out in deep powder it also take a while for the sled to get going because if doesnt want to pull. Once it gets rpm it is fine. If I can get a run it holds the RPM well as long as it is not a long pull. It always seems to happen at the top of a hill Is is possible that the sled is shifting back to the stteper initial angle causing my problem. The sled came with a 56-42.36 . I also have a blk/white secondary spring with a SLP shim

 

[Boston Racing]

Is it also possible that I just dont have enough power to pull the 19/42 gearing?

 

[AKSNOWRIDER]

I have a 660 rmk / 155 with a 62-38.36 Helix in it that Carls sold me. What is happening is on a long pull or in deep powder the sled will not hold rpms once at low track speed. If I can get a run it holds the RPM well as long as it is not a long pull. It always seems to happen at the top of a hill Is is possible that the sled is shifting back to the stteper initial angle causing my problem. The sled came with a 56-42.36 . I also have a blk/white secondary spring with a SLP shim

boston do you have any delrins in it? if not try 2 delrins (1 on each end of the secondary spring)..they help the secondary keep from binding up which is what it sounds like yours is doing, smoooths out both the upshift and the backshift....

 

[Boston Racing]

I do have the delrins in it.

 

[AKSNOWRIDER]

I do have the delrins in it.

uh-oh..that makes it tougher..hmm.....let me think about it....
my guess is you need more secondary initial pressure...your pulling as much initial helix angle as I am on my D-8..hmm..let me think some....

 

[Boston Racing]

My thoughts are it the steeper initial angle lods the motor too hard or " upshifts" too fast it would be like starting in too high a gear adn if the clutch backshifts at low trac speed it hits the initial higher gear. I dont know if that right at all. Carls also say they normally run 58-60 gram weights but the 7/800's re not running that kind of weight at 10-12k feet. With my theory a 56-38.36 might help but at 100 bucks a helix I would some other folks educated opinions.

 

[AKSNOWRIDER]

My thoughts are it the steeper initial angle lods the motor too hard or " upshifts" too fast it would be like starting in too high a gear adn if the clutch backshifts at low trac speed it hits the initial higher gear. I dont know if that right at all. Carls also say they normally run 58-60 gram weights but the 7/800's re not running that kind of weight at 10-12k feet. With my theory a 56-38.36 might help but at 100 bucks a helix I would some other folks educated opinions.

hmm it should pull it..the stock 2010 600 shows pulling a 60/40/.45 so it should pull it...I assume the black/white is 160/260..if so I would throw the slp black/yellow at it(180/260)..then add the green/pink(stock on 09 is 140/330 the green/pink is 160/340) in the primary and you may need to add some weight back to keep full shiftout rpms down...

 

[theultrarider]

Another thought is simple jetting. What do your your plugs look like? I know on my 800 mod if I start to run fat, that is the way mine acts. I suspect your 660 is the same. Will pull fine until you put a heavy load on it, then won't hold the r's. AKSNOWRIDERS suggestions for clutching sound right on to me, but check you jetting too.

 

[Boston Racing]

Jetting is at 13-1 or so according to my Wideband 02 sensor.I can go any leaner because we cover 3k or more in elevation change and the temp can vary alot. I did lean it down with no change though.

 

[Boston Racing]

hmm it should pull it..the stock 2010 600 shows pulling a 60/40/.45 so it should pull it...I assume the black/white is 160/260..if so I would throw the slp black/yellow at it(180/260)..then add the green/pink(stock on 09 is 140/330 the green/pink is 160/340) in the primary and you may need to add some weight back to keep full shiftout rpms down...

The RMK 155 still shows the 56-42-.36 I will try the spring though. What effect does the the stiffer first number on the secondary spring have?

 

[AKSNOWRIDER]

The RMK 155 still shows the 56-42-.36 I will try the spring though. What effect does the the stiffer first number on the secondary spring have?

it will raise engagement rpms and off and back on the throttle rpms...and it should help when the sled backshifts on a climb...