pierce

My wife has a step through comfort bike, in fact, she's on her second, since her first got wiped out in a car accident (bike was on front trailer hitch carrier and got smashed beyond all recognition).

the replacement didn't have the bouncy-post her first did. I never much liked those bouncy-posts, so was looking at alternatives... a thudbuster seemed perfect but was too expensive for this $225 bike (ok, its a $500 bike we bought for $225 including shipping)....



I found a Moxie seatpost on ebay cheap, nearly new condition.



Works great, except the elastomer is just way too soft (ok, me and my wife are both on the plus-size side of things),a nd it pretty much bottoms out.

well, Moxie is out of business, Cane Creek dba Thudbuster sued them into oblivion over patent violations, so no replacement parts.

I'm thinking if I can find a suitable elastomer, I can cut a block of it to fit... but I have no idea where to look for something like that.

Wondering if anyone has any suggestions?

giantcfr1

Got me buggered.

Do you guys have "Hardware House" over there? You know, the warehouses most men could spend all day at. ie. the IKEA for Tradies

Edit, Hardware House was bought by Bunnings in Australia.

pierce

We have various local hardware stores, plus regional chains like Orchard Supply Hardware, then the megabox chains like Home Depot. elastomers just don't fall into the home construction space.

I was hoping maybe there was some sort of auto suspension piece I could cut up, but my car wrenching experiences have mostly been VW and Volvo and theres nothing suitable on any of those

SHOFINE

You reckon the replacement for the thudbuster will work?
https://www.jensonusa.com/!NCsZ-2Mo0D...FQtxQgodFk8AYw

pierce

I looked at that, but the ST is much smaller, I'm not sure it would fit. sigh, none of the LBS's I've visited carry these things.

I toyed with trying to retrofit the larger thudbuster's cylindrical rubbers. but I think I found a source of larger blocks for cheap I can experiment with, they are used as leaf spring pads for truck suspension upgrades.

plan B is to get some 2-part polyurethane and try casting my own

giantcfr1

What about the thingies they use on engine mounts of cars

pierce

and today I hit upa local non-chain car parts place, the counter guys werre amused, pulled out all sorts of things, a black rubber 'coil spring booster' from the towing accessories section was almost exactly the right size.

I trimmed off two lobes from one end and it just jammed in as-is, tightened the preset screw down some and hey, it works. hardly sags under my 210 lbs at rest, and over some bumps in my driveway, I got maybe 50% travel worse case.

best part is, I got a spare block if this one fails, hah hah. 2 for $6!!

giantcfr1

Brilliant

kevinjg

Hopefully, you will get this message because it has been a 1/2 year. Can you share the "part" that you used to replace the old Moxie elastomer block? I found one of these and need to replace the elastomer but having a tough time finding one. Thanks, Kevin

pierce

I dunno, it was a block of black rubber just about exactly as thick as the Moxie, and wide enough that I had to squeeze it into the moxie when it was at its widest setting. both ends of this rectangular block had a deep notch in them, by trumming one of the lobes off one end, and the opposite lobe off the other end, it was roughly parallelogram shaped, and jammed in their just about perfectly. I used the preset screw on the moxie to put enough pressure on it that it hasn't walked out.

as I said, I think it was sold as some sort of coil spring booster or something like that.

kevinjg

Something like this?

or this?

pierce

the second ones... but the long sides were flat, not rounded. dimensionally, if you back out the preset screw on the moxie and measure between the vertical bars when its upright, this block was almost exactly that wide, and trimming the nubs off one end made it just about exactly the right length.

kevinjg

Thank you! Maybe more like this?

pierce

yeah, that looks like it. I *just* found my spare (came 2 to the SKU)... (grabs caliber...)

3.5" long x 2.0" wide x 1.25" thick. between the notches, its 2.5", so I guess when I trim two lobes off one end, its about 3.0" long overall.

kevinjg

Thanks, again! Great information.

lopek77

Drill some holes in it to make it softer/for skinny butt rider.
Great "old school" ingenuity!

JimQPublic

PIerce,

Now that it's 7 years later and thankfully you're still active on Bikeforums, how did it hold up? I've had my Moxey-equipped bike hanging in the garage for several years and just pulled it out. As soon as I started riding I felt chunks of something hit my legs and I was sinking down. Yep, the elastomer completely disintegrated.

So I'm on a quest for a chunk of rubber. Do you think "Superior 18-1701 Rubber Coil Spring Booster, Large" would work? it's listed on Amazon as 7"x5"x1" but sometimes Amazon's listings are for the package, not the item.

pierce

yup, still holding up fine.

that looks just about what I got at the local autoparts store... trim to fit such that its a tight squeeze to install. its quite stiff, but my wife is quite hefty, so its a nice match... if you're lighter, and its too stiff, you could probably drill some holes in it.

SteveKB

Would Skateboard Bushings work?

pierce

this is my customized Moxie, with the trimmed spring spacer thats been on it for like 5 years. I electrified this bike a year or two ago, and this is a crop of a copy of a picture of the work-in-progress, so ignore the crazy angle of the rack, and all that uncovered electric stuff on the back ... btw, 750 watt rear hub motor on a ladies 'comfort cruiser' is a bit scary, heh. I power limited it to 500W, and its a little saner.

HorizDropPlz

OK I need some help with this, I'm getting frustrated trying to get this thing working. I got the coil spring boosters (also called spacers , risers , stabilizers and blocks) and I even compared 3 different brands to find the softest one(Napa had the softest).
I cut the rubber block to try and match the shape of the original elastomer... SEE PIC.
I even took the aluminum inserts out of the original Moxey roasted elastomer to use in the rubber replacement.
I cut recesses out of the sides of the rubber coil spring booster. I lined up where I needed to cut the recesses out of the new rubber block by installing it then taking a 90° dental pick like tool to mark the rubber through holes in the seat post frame. They lined up perfectly. I reinstalled the new rubber elastomer and this seat post isn't moving I mean no suspension.

Is it the shape I cut the rubber? I see in the other picture you cut off 2 lobes from the same side and weren't trying to get top and bottom corners to fit into those 2 rounded corners of the post's frame like I did. I was trying to make it fit just like the other Moxey seat posts I've seen (posted another pic).
I needed this post because it's going on a bike that takes a 25.4mm seat post and it's hard to find good suspension seat posts sized 25.4mm. Cirrus makes a post that's 25.4 but it's $250
There are older thud busters that are 25.4 but they don't come up often and sell fast.
I just need to figure this elastomer situation out.

I tried to contact many people on ebay that were advertising polyurethane blocks, silicone rubber blocks and couldn't get a word back.
There was some poly I could order and cut to fit but all I'm getting is the shore hardness & no other info and its not super cheap for something that might work.

Now I'm seeing there are kits on amazon where I can make my own poly but they all say they are for mold making... would they still work?

guess I can't post pics yet

HorizDropPlz

I belive the picture of the moxey seat post you have in this post (I had to erase it from your post I quoted because I can't post pictures yet) has the wrong elastomer. I think that elastomer is for another Moxey seat post called the Moxey Pro. I think the Moxey Pro was supposed to have 4-5" of travel.

HorizDropPlz

I'd really like to find someone that knows about these DIY make your own polyurethane kits I'm seeing on amazon. I'd like to figure out what shore hardness I need and if this poly could be used to make an elastomer for the moxey seat post I picked up.