thomson connection question

Ive heard that the thomson seatpost can connect directly to the cf seat base without the rail adapter. which cf base do i need, and how does this work? thanks anyone that can give me advice.

Those seat bases are a custom carbon fiber design by Scott(S_Wallis) . There is a pic of SteveOwe’s saddle about half way down this page:

Well, Krashin’ Kenny is half right, just not fully. You can directly attach a Thomson post to a regular cf seatbase and still retain some element of adjustability.

The tools you need are:

-bench grinder, face sander, belt sander, hand file, or angle grinder, or in a pinch, a hacksaw (any of these will do, I would use the belt sander, but i only had my bench grinder at hand when I did it. Note, if you grind aluminum on a bench grinder you will need to re-dress the wheels afterwards)
-Power drill with a 3/16"-1/4" bit, preferrably a stubby (jobber) bit. Basically any bit that will drill a hole big enough to fit the screw for the post through. The closer the fit the better.
-Dust mask
-replacement screw oir preferrably screws that are 1/2" longer then the original thomson screws. As long as they are allen head and have the same threads as the thomson they should be okay. Try and match the material, though
-scrap innertube
-scrap light sheet metal, aluminum, or thick-ish plastic (1/16"-1/8")
-Scissors or something to put holes in the above materials.

I used a phillips head screw that came off the spark guard for my bench grinder to replace the thomson screw. I use the original thomson screw opposite it to tension and angle the thomson. It’s a bit harder, but works.

Any cf base will work, I used the miyata style because it was what i had.

If you want full instructions I can give them, but otherwise I’m going to save my time.

Do you have any pictures of your setup? I can’t quite picture it based on the description.

I know it’s hard to see, but between the post and the base, there’s the bottom part of the thomson mounting bracket. IT allows me to retain a good degree of adjustability, and helps to distribute the forces over a larger areas of the base. This is a thomson I got on Ebay for $45 (incl shipping), so I already know the warranty is no good. I ground a large part of the bottom plate to flatten it and remove material from the sides and corners of the plate so that it’d fit between the ribs on the base. There is alsoi a triple stacked piece of thick innertube to help dampen things. On the other side there is some 1/16" plastic and 2-3 layers of innertube under the cylinder nuts to help distribute the force on that side. I don’t have any other pics since that is my only seat and it’s currently mounted on a miyata post on my muni.

Ah, I see now. That looks like it should work just fine. Similar in style to Scott Wallis’ design.

I do like that style of mounting for the seat. It saves some weight. But more importantly it gets rid of the rails which have a tendency to break. The welds on the rail adapters are not all that strong.

Thanks. It is almost exactly the same as Scott’s, except cheaper, easier to make, and probably a bit weaker, not that the last part matters. Both of your reasons are important parts of why I did it, but also my reason is that for trials I didn’t like the idea of being able to get my finger caught in those rails.

hmm ok so you get a regular base and drill it for the two bolts in the thomson post and take the top part off. inner tube makes sure nothing cracks. i wonder if longer bolts are necessary tho.

is anyone breaking Steve Howards Kinport adapters? i havent had any problems with the 3 i’ve had (except the Titanium one but that doesnt count)

the welds on the Kinports are way better than the Wilder ones.

How much does that connection cost, and where can I get one at?

I’m almost thinking of converting to a KH fusion air seat with his handles, and a carbon fibre seat base with that cf connection, to replace the '04 KH seat and Wilder Bracket I’m already running with a Thompson. Nothing necessary…I only bought what I’m running now in September, but I would someday like my seat stiffer, and more low-profile, with the added comfort of air.

Dependiung on where you attach the post to the base and what base you use, you could find a spot where you don’t need longer bolts, but I doubt it. You need to make sure all of the threads of the cylinder nut are engaged.

You will need to grind the top of the bottom plate to be relatively flat, and round some of hte corners since they will quickly go through the rubber and crack the cf.

The connection is the cost of the materials that I listed and a thomson post. You get one by making it.

Jag, what ever happened to the titanium adapter after it broke? Steve re-welded it, right?

Ryan Atkins and I both did that. But you need a stiffener plate because the carbon fiber will flex alot! ryan made his out of alluminum I made mine out of carbon fiber. its really simple. mabey I wont be all lazy and take a pic. HAHA like that will ever happen.


i sent it back to be re-welded but that was the last i ever saw of it. Steve’s a very buzy guy and i didnt want to bug him about when it would come back. its probobly a paper weight in his office or somthing, a light one too :wink:

Yeah, I’m thinking of starting to play around with Ti. Still gotta get better at TIG welding, though.

nobody answered my question. Where can I get the Wallis cf adapter for my thompson post?

You get it from scott himself, but its not an adapter, its integrated into his cf seat base…send him an email and hell put you on his wait list.

Contact Scott Wallis

The CF Thomson adapter is an entire CF seat base along with some special hardware.

John beat me to it.

what are the prices of these objects? the base, the cf rear bumper, the handle…

Thanks a bunch!