M7/M8 Suspension bottoming out

[ViperTurboPete]

Last spring I installed my 141 Cat suspension with a mixture of M7 and M8 components. This suspension has no torque links and are the new design rails. Anyway, I am bottoming out in the bumps regularly. My rear springs are on the stiffest setting and I weigh 160lbs. Are there stiffer springs available or is the Zero Pro rear shock in need of a re-charge?

 

[RXMax]

They stiffer springs are the way to go. I am 250 in gear and would have a tough time bottoming mine out. I also know of guys that get their zero pro valved stiffer along with overload springs if you are real aggressive. I have mine on the middle setting.

 

[JDKRXW]

Sorry Max, I've got to disagree. If the rider is 160 lbs. and bottoming, rebuilding and revalving are the first things I'd be doing....before the springs.
I did both (springs and shock) on my Warrior with a Crossfire skid and got the bottoming under better control with the shock work.

 

[RXMax]

Probably correct for the weight of the rider. I was unsure of the mileage on the shock. I think the M7 has a little different geometry than the Crossfire skid as well. The M skids are mounted further back than Crossfire skid so the suspension is loaded differently. One quick question for the original poster. What is your set-in when you first get on the sled?

 

[freelheeler]

having similiar issues with new track camo extreme, i've got an m7 153 with fox shocks

what the best way to be sure the shock needs rebuilt? and who rebuilds them and approximate cost?

heavier spring, where can they be purchased how much and can the same be accomplished with an overload block?

thanks

 

[RXMax]

Go to the arctic cat dealer. Heavy springs for M7. they are in the parts manual as an option. Any arctic cat or polaris shop can rebuild and revalve the fox shocks.

 

[ViperTurboPete]

Thanks for the info. I will look into the springs first and go from there.

 

[freelheeler]

any luck with the springs, my local dealer can't tell me if i already have the heavy duty spring??? has anyone use the overload blocks??

thanks

 

[RXMax]

Measure the diameter of the spring with a caliper. Stock are .375 and they go up from there. Mine are .405 and the part numbers are 0704-892 and 0704-893. The titanium are .488 but they are spendy.

 

[freelheeler]

thanks
what's the rating difference between the springs? the local dealer had no idea is it 5% or 50% increase in stiffness? or is it measured by weight?

i went ahead and ordered overload blocks that are a 15% increase which may be a start? say i'm 230# with soaking wet and with gear that'd be about 35#??

i'd like to find a balance and not end up with a trenching fool, and i like the adjustability of the blocks. rxmax how much do you weigh geared up and does your sled bottom out?

 

[Powder Nomad]

overload blocks

Hey Joe... where'd you order the overload blocks from... straight from Cat, or somewhere else? I'm having the bottoming out problem as well. course being 270 fully geared up probably doesn't help. :exc:

 

[RXMax]

I do not have a service manual to get the spring rates other than the wire diameter listed in the parts catalog. I am 270 in full gear with my stock blocks in the 2nd position with the overload springs and I cannot bottom it out. Hi Performance Engineering sells a nice set of billet overload blocks. Down towards the bottom of the page. 10% increase in the first two positions and 15% in the 3rd. $42.95

http://www.hiperf.com/cgi-bin/sh000001. ... a210_2d516

 

[freelheeler]

rxmax that's exactly what i bought, they also have a 4 position block that goes to 10% max sounds like it may have more adjustability?

i'm now looking into an 'over load assembly' apparently most 2 up arctic cat sled come with them and you can flip up a lever to prevent bottoming out with big loads and put them down if your solo. i'm looking for a used set, new they're over $125!!

Nomad how's the sled running? could have used you last weekend, had to start carrying my only other anti stuck device a 'winch' not so much for my sled but the folks i've been riding with. the snow is freak'n deep in this area. later

 

[ViperTurboPete]

I finally got around to buying some new M8 springs (.405") and installed them the other night. I went for a ride yesterday on some major stutter bumps yesterday on the softest setting and didn't bottom out once with my 12 year old step daughter on the back. The M7 springs (.375) didn't work worth a crap.

 

[doo_man]

I bumped into a another yammy with a cat skid in it recently and same problem. Crossfire skid in a Vector, tried new springs and still bottoming. He tried adjusting the mounting points and it got better. But he is still not happy?