replacement shock for 856

[richard reeves]

I just found this site and need some help. I have a pro-flex 856 with the rubber shocks and they are shot. I would like to replace them with spring. Any help would really come in handy.

[Mike_Farris]

This question comes up all the time. Since lots of others on the forum have answered this question, I guess it's time for someone else to reply. (BTW, I checked the FAQ, and didn't see the answer.)

Here's your options:

Get a Speed Spring for your current ODS shock from MountainSpeed - http://www.mountainspeed.com. Should be around $50. Slap the spring on, change your shock oil (if you haven't done so recently), and you're good to go.

Get a used Noleen NR-2 or NR-4 from eBay or another source. You'll be looking for a shock that has a conical end piece, so that it will fit into your strut. There is a collet that sits in a conical depression in the strut. You'll have to get that collet out of the strut in order to go this route. You can get a used Noleen for less than $100... but you might not be able to find one in a timely fashion. Also, some folks have had good luck with these shocks, while others haven't. I don't think you can get these shocks directly from K2 anymore, so you'll have to go used.

Buy a totally new shock from Risse Racing or Stratos - http://www.risseracing.com or http://www.stratashock.com. You'll spend anywhere from $200 to $350 for a Risse (depending on the shock) and $275 for a Stratos Helix Pro. The Risse units don't have coil springs... they're air/oil shocks. The Stratos is air/oil/coil spring. Once again, you may or may not have to remove the collet in the strut to use one of these shocks... Risse makes shocks that use the stock attachment method, but I'm pretty sure the Stratos shock requires that the collet be removed.

BTW... if you take a look at Risse's page, they have a picture of a shock with a conical end piece on the page showing the applications of their shocks to Pro-Flex bikes. That's the type attachment you're looking for in a Noleen shock.

Hope this helps. Good luck!

[Dave]

I have an old Proflex 755 with rubber shocks.  

All I want is new rubbers, is there any place I can buy these.  It would be nice to upgrade to the Noleen shocks but I really can't justifly spending all that money on this old bike.

Does anyone sell these anymore or am I SOL?

Thanks

-Dave

[Mike_Farris]

Well, I just checked the price for the SpeedPro kit from MountainSpeed... they're asking $38.50 plus shipping. You can check with some of your local bike shops about elastomers, but they're usually around $16 a set. And they wear out after about a season or two.

I'd suggest getting the springs. It actually works out cheaper in the long run, and based on input from others on the forum, you'll like your suspension better.

However, if you REALLY want new elastomers, you can check with the source listed in the posting at the very top of the list, or check with Aardvark Cycles... http://www.aardvarkcycles.com.

[Dave]

I called MountainSpeed and they told me they don't have anything for a 755 as far as spring conversions, they have stuff for the 756 but not mine, they said I am SOL.

But I recieved an email from Davedrumm and he said he has the elastomers in stock, hopefully on Monday he will be able to ship them out.

-Dave

[mfgp]

I ran into this last year when I tried to upgrade my 755 shock.  Yours is a non world cup also?  

I ended up with new elastomers from REI.  

[Mike_Farris]

Sorry for the bad advice. I took a look in the "How Tos" section of the forum, and they had a PDF file of a 755 frame assembly... and it was a World Cup frame. I had no idea that they made 755's with the older shock style.

Oh well... live and learn...

[rapiddescent]

SHOCK HORROR: the proflex bikes never used elastomers.  

They used MCU - Micro Cellular Urethayne bumpers.  the problem  with this flavour of MCU is that UV light rots the MCU and makes it go hard.

if you take a hard MCU and chop it with a knife, the inside core will be soft and spongey.  the 855heads came up with ideas to boil/microwave MCUs to make them softer but all were short term solutions.

MCU's are used as bumpers in vehicle shock asorbers but usually are completely sealed.  

If you have the phase 2 world cup frame; 856, 956, X-series, 657 with ODS shocks - then just use a mountainspeed spring as others have said.

If you have the phase 1 wc bike (that hank djernis won the 1996 XC world cup race on) , 656, 855, 955 - then find an 856 strut or add a Stratos Strata shock (if you can find one).  you could also fit new MCUs - but you have no damping.

If you have the even older bikes, 954, 854, 655,  - then you'll have a tough time upgrading.

hope this helps,
callum
rdi

[mfgp]

Actually my elastomers...I mean MCU's...didn't harden.  They melted.  I put the bike in my car one spring day and drove a couple hours to a trail.  When I went to unpack the bike, it was as if someone had smeared melted bubble gum all over the inside of the car and all over the frame.   [smiley=diaper.gif]  They seemed fine when I rode a week before that.  What is really strange is that the MCU's continued to degrade even after I brought the bike home and put it in a cool garage.  The material was running fluidly and did not harden back up.  Eventually they turned completely into liquid.  

That was the front shock.  The rear started going down the same road, so I picked up a spare pair of MCU's from my LBS.  They had some new old stock units in the bottom of a drawer somewhere.  Those immediately degraded and started to melt after a few weeks.  The new ones I ordered from REI have been fine since I bought them approximately a year ago, even after being left in my car in the Florida heat.    

[Scott]

 "Eventually they turned completely into liquid. "  Sounds like a plot from the X Files....

[rapiddescent]

thats what I was thinking.  bring agent scully.

A carribean bloke once told me that he replaced the elastomers in an 855 for wood.

brilliant idea.

callum
rdi

[mfgp]

It was pretty spooky.  I should have kept an eye on the stuff after it oozed out the garage door and around the corner....