Is it OK to cut an elastomer ?
 

This is the contraption I am making for the rear "suspension" of an Ozone. 2 seems too little, 3 is too much.

Dependez...
Since I don;t know what an Ozone is, nor what 2 or 3 refers to, or does....
Elastomer usually fills a set 'space'. Depending on how the 'space' is handled, will depend if 'cutting' (in length...) alters the 'function of the mechanism...
If a set 'length- is needed for proper function, then any 'cutting' might cause malfunction of the mechanism (like in the elastomer function in a Shock Stop stem...)
also the elastomer, if used as a 'spring', will alter in the same way as if you cut a coil spring - less coils to a length of coil spring makes the spring stiffer...
Ride On
Yuri

If you posted a photo, it didn't come through.

Make sure the elastomers are the correct ones for the bike including length and durometer of the rubber don't alter it or it could have effects on how the bike rides.

I think the bike is a wally-mart level hybrid so nothing to really put a penny into but I think the OP has already sunk a ton of money and time into it and either has to figure out a non-existent ladder to get out or just dig through to the other side which will cost more.

Ozone pic
https://cimg2.ibsrv.net/gimg/bikefor...2117dc04ba.jpg

The elastomer is where the long bolt is under the seat.

Its pure compression and the elastomers are

https://cimg5.ibsrv.net/gimg/bikefor...a7cbfd9ec6.jpg

They were bought for a slightly different project ~10 yrs ago but are a bicycle part.

I want to cut 1 in 1/2 across the diameter, not length wise.
Should the elastomers have preload on them ? Because 3 will put them under massive preload. Like install them with a ratchet strap on the frame to compress them. In fact even 2 1/2 will likely require that. 3 will just need an insaner amount of force.
This bike is rather well built for being an academy sports store brand.

No, not much $$ in it yet. A lot of elbow grease though, sanding and polishing. I am loving the work I did on it though. May clear coat it but the problem is I 1000000000% suck at painting. Runs, un covered spots, pait that may not dry too well etc etc.

How much compression do you need? I'd put in 2 and adjust length with washers and try it. Works, feels good, leave the washers in and call it a day. Then if I felt the need for more compression with a partial 3rd one. Cut it long, try, cut shorter as needed until you're satisfied. Trial and error.

Wipe on clear Poppys or VGG

​​​​​​https://www.vicegripgarage.com/colle...tina-preserver

How much travel does that rear suspension have? You typically want to set up a suspension so that when you sit, your body weight causes the suspension to compress a little bit, but not too much because you want to leave the rest of the suspension travel for actually hitting bumps.

Figure out how much suspension travel you have first - without any elastomers. Then put 2 in and see how much compression your body weight causes. If it's more than 5-10% of travel, then you may need a third or another half of one - it's ok to cut. Try again. If the suspension compresses too much from your body weight, then your elastomers are too soft. If the suspension doesn't compress at all, then your elastomers are too hard.

In the bike pic, basically the elastomers will move if wiggle them. Its got 0 preload.

https://cimg4.ibsrv.net/gimg/bikefor...46786986a3.jpg


Eyeballing it - Maybe I need to tighten that bolt, however that is a hex headed bolt with out a washer sitting in an aluminum housing. So, I will swap it out for a SS bolt with a washer before I do that.

The 2nd reason I'd cut it is that the elastomers are sort of made to lock into one another. Its got an indent on the bottom and a "nose" on top. The nose is all that's making contact with the frame. If I cut it off, and put another 1/2 sandwiched between washers then the contact will be full diameter instead of just the nose.

Wow, never thought I'd see another Ozone500 Silver Canyon on bikeforums.net!

MIne is alright, but the pivot is so sloppy I can feel the rear triangle kick out quite a bit on highspeed turns. Luckily I only ride down one really steep hill with a fairly sharp left turn once in a while :)

The only side view shot of it I can find right now is a pic where I was actually photographing a flat-barred Serotta:

https://cimg6.ibsrv.net/gimg/bikefor...9358bfbe11.jpg

As they say time is money...

You don't want it loaded up at rest unless there is also a bump stop or negative spring so it doesn't clunk at the top of travel.

A typical MTB setup uses about 1/4 of the travel for the rider weight

It wont clunk, I also plan to put the elastomers in a radiator hose which as we know is one tough mofo. In fact I probably should assemble it with it because it may end up rigid.
The swingarm pivot is tight as hell on this bike. But I'll check it again.
Tim is money only if you're doing something you dont enjoy.

Yeah, mine's never topped out with a clunk, no matter how I have it adjusted.

if you cut it too short, you will lose any preload... you will NEED a preload amount

cut 1/8" slices at a time, or maybe 1/4" at a time.....

you WANT some preloading, or it won't work well... most of that type of bike i've seen use substantial preload to limit motion of the suspension until you hit a pothole or something..
it's just for big hits, not every little bump or ripple..