I am looking at getting a new dropper post to go with my new(to me)frame.

I am liking the Thompson posts however they are 125 mm drop. My current set up is 100mm dropper and a smaller seat tube (27.2 Hi-lo).

By my rough calculation I believe that with the post(thompson) fully inserted it will be 5-8mm higher than my current seat height – ie too high (when I build it up with my current post I will know for sure).
The new frame is 31.6mm so I do have alot more options. (Reverb 100mm drop for example).

So, the question is does anyone run such a set up , where they never fully extend their post, or is it s daft idea that will be a pain to live with?

All opinions welcome.

(I am tempted to buy one in the upcoming sales and not not install it until fully sure of compatablilty thus being able to return it unused for a full refund should I decide against it)

I thought I would have the same problem going from a 100mm hilo to a 125mm reverb due to my short legs.
I don’t know about the thompson but on the hilo the gap between the bottom of the saddle clamp section of the post and the saddle rails is quit large and found there was not a great deal in the overall length of the reverb and hilo when inserted the maximum amount.

It was a few mm which I quickly got used to as running it short of fully raised would be a faff.

No, how do you plan to get it at the right up height?
It will be a pain in the arse…..

So, the question is does anyone run such a set up , where they never fully extend their post, or is it s daft idea that will be a pain to live with?

Pain.. as you’ll constantly be ‘fettling’ with the lever to try and find the correct ‘less than full stop’ extension height for pedalling comfortably.

Probably not what you mean but i had a dropper that dropped 1″ and then another 3″ in steps. I used to ride most places dropped 1″ and only put it at full height on long climbs. And i dropped it fully and dodgy bits

what about a 4″ DOSS

You could always keep the oil pressure down so it never fully extended….

Not really, It would be an arse.

My Thomson post doesn’t extend all the way now anyway. Sits about 10mm into its travel.
I’d send it back to be fixed but tbh it’s perfect in every other way so I can’t be bothered.
Suspect it is a bit daft buying one & hoping it develops the same fault though…

Not going from hardtail to full sus by any chance?.
To get the same leg extension as my hardtail I run it slightly higher on the full sus to counteract the sag.

I run it slightly higher on the full sus to counteract the sag

Only works if your seat tube is not fixed in relation to your bb, trying to think which has frames are not.

Fibre, you are correct.
I shall build the bike up(when I get chance)and then get the tape measure out and plan from there.

What pedals/shoes do you use?

I run it slightly higher on the full sus to counteract the sag

Only works if your seat tube is not fixed in relation to your bb, trying to think which has frames are not.

URT?

Yea – I have this problem when I fit my reverb – which I only do when going on hols to do some real down hill stuff – otherwise for normal XC I just use a fixed post.

It doesn’t insert enough & I have to play with it to get a suitable ‘up’ adjustment. Last time I used it I put a zip tie thro the saddle rails & top of the frame by the seat which stopped it going any higher than the ‘right’ height. The loopy zip tie was a bit of a pain at times with the post dropped – but it’s a solution……

Sorry ignore what I said, I’ve just realised the gibberish. Don’t go on forums sleep deprived and overdosing on festive food :P. I actually run it higher to counteract the shorter crank on my full sus, and it’s useful to lower it with the remote when stationary (saddle sits higher compared to my HT, higher BB and shorter crank).

If you cant get the correct length dropper and you have a couple of saddles check the rail to saddle top height for something shallower, might get you a few mm. Same with crank lengths, shorter crank will reduce leg extension if you have options.