Trampa bearing adapters - how to install?

I have some supastar hubs and the bearing adapters to use bearings which will fit 8mm axles. I assumed when I purchased them that the bearing adapter would be fitted in the center of the hubs but they don’t seem to be the right size.

how do I fit them? they fit into the side of the hubs but that seems a little weird, am I missing something?


Yes i was missing something. I needed to pop out the star shaped spokes from the hub amd flip them around the other way, everything fits beautifully and the bearings are lovely and snug but can still be easily inserted and removed by hand.

amazing engineering by Trampa

you take out the black middle spacer part between the rims and place the adapter in for that.
as min that´s how i thought it works.
there should be a maual to it as well. will look now.

description says that:
By simply replacing the regular Spoke support spacer that comes standard in SUPERSTAR & MEGASAR wheels, it’s possible to fit 5 Inch GUMMIES Tyres, 6.5 Inch Urban treads tyres or any of the 7 & 8 Inch tyre options TRAMPA has to offer.

yeah, that’s what I thought until I tried and it doesn’t fit!

the adapter diameter is too wide to get into the hubs, looks like I’ll have to file it down, FFS it’s going to be a long night followed by a long journey to Paris

can you post a picture from how it look now?

I am about 50 miles from the workshop right now :frowning:

perhaps it just need to be tapped in with a mallet or an arbor press, but I had assumed it would be a push fit sort of thing

should be i think.
maybe @trampa will be online in the next time and can help you with it.
Frank we speak about this

to be fair i could be missing something obvious, working 18 hr days 7 days a week right now so i have the mental and physical prowess of a drunk floridian on bath salts at the moment


By looking at it I assume you remove the original supporter and press fit that adapter to the bearing seat.?

yeah, that is what I assumed too, but it didn’t fit the way the original plastic spacer fitted, seems like the diameter is a bit to wide and didn’t want to force it and break the adapter before finding out if I was doing the right thing

It’s probably a press fit adapter. That would explain why it’s bigger. Anyway it should be about 0.01-0.02 mm bigger in that case. You will feel if it’s going in with a little bit of force.

if it’s pressfit that is going to make opening the hubs up to change tyres “interesting”


That’s right :smile: You have to press it out everytime…
Probably just a monday example.

oh well that’s fine, it’s not like I am going to a racing event tomorrow or anything.

I am not taking an arbor press with me that is for sure


ironically the bearing seat in the adapter is so loose they fall out :slight_smile:

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If you are using a truck with and extended axle you can use 8x28x9 bearings, no adapter needed

I have bearings that fit, but not the correct length spacers… anyone know the lengthof the spacers? I may be able to print some

Turn the spoke inside out. If tolerances are tight, heat up the spoke and throw the spacer into the fridge.


They should be 18mm, but there is a bit of variation between hubs

What I do is to make them a bit taller and secure the bearings with retaining fluid

Put one bearing with retaining fluid, let it dry, assemble the wheel, put the spacer, and another bearing with retaining fluid and install the wheel on the truck, let it dry, you have perfectly fit spacer and a rattle free wheel