Seatpost exposure - how much is too much?

Gabbo

I've extensively discussed with others what the appropriate bike for myself may be, due to my freakishly long legs and shorter torso (89cm inseam, 186cm height).

I also heard that a method of adjusting the height of your seatpost is to multiply your inseam by 0.889.. though not sure whether this applies to time-trialists or is in general, complete crap. If this is true, then my saddle would need to be about a shade under 78cm.

I've concluded that due to my in-proportional body parts, a Scott Foil is out of the question. For a large, it has a seat-tube length of 50cm. Any larger, and I'll be seriously compromising on reach. The large in CAAD10/Supersix has a 54cm length seat tube. The Canyon, on the other hand, has a seat tube length of 57cm which in this case is larger than the top-tube itself.

My choice would be the Cannondale, but would the drop be too much? Would there be too much seat post exposure?

Thanks in advance

chrisvanderkaap

I have often suffered with the same problem, having a inseam of 98 with a height of 195. Check the geometry of those bikes with a shallower i.e. 72 instead of 73 seattube angle. this corrects the reach for people like us with long legs. I know Giants compact road geometry (I own a tcr advanced size L) has this. Even though It's a pretty steep drop it's not uncomfortable because of the reduced reach. In any case I wouldn't really correct for the top tube discrepancy with a much less than average stem since imo seriously compromises handling.

letap73

Nobody is going to solve your problem on the internet in a satisfactory fashion. Depending on where you are based you could get a poster on here with supersix/caad 10 56 nearby to let you try their bike out. Alternatively go to a cannondale stockist like EPIC cycles - do a test ride, they will then build a bike up for you at a good price.

alihisgreat

That multiplier is a load of crap just designed to give you something to start with.

I have an 83cm inseam and run a saddle height of 790mm.... 780mm would put me comfortably in the middle of the 'acceptable' range that most standard bike fits work off.

It is an individual thing.. not only affected by leg length, but also things such a foot length, cleat stack height, sole thickness etc.

If you get a decent bike fit, the fitter should be able to recommend some framesets based on that - I think retul have a database that they just plug your numbers into and some recommendations pop out.

Gabbo

Thanks guys,

know where the best bike fitting places in London are?

Gabbo

I have actually found a Retul 3D Bike Fit for £185

Not sure what others have paid for their bike fit before. Maybe, just maybe, it could be the best sum I spend towards a bike!

danlikesbikes

Gabbo wrote:

I have actually found a Retul 3D Bike Fit for £185

Not sure what others have paid for their bike fit before. Maybe, just maybe, it could be the best sum I spend towards a bike!

Sounds about right for that fit, our local place does the same price too

pkripper

I just align the top of the saddle with my hip bone. It's pretty much bang on the same as the bike fit height

ShutUpLegs

Optimum seatpost exposure is 10cm

Don't most places do a discounted bike fit if you buy from them? Just a suggestion as £185 seems a tad high.

jameses

I guess a traditional/horizontal (rather than compact/sloping) top tube would give you a longer seat tube, so wouldn't need to expose so much of the seatpost.
So long as you're not going past the 'minimum exposure' mark on the seatpost, you should be fine. FWIW, on a 350mm post you can generally have up to about 250mm on display.

aka Arthur

This is all guesswork. You need a professional bike fit.

It's the best cycling 'upgrade' you can buy... and you can take it from bike to bike (as long as you don't grow or shrink any time soon!).

FransJacques

Every seatpost has a limit on it. That plus 4-6mm is how high you can go.

More seatpost looks better to me, my bikes have 79.5cms BB to Saddle Top and I like to show lots of post. From seat collar to saddle rail on my 2 best bikes is about 20cms. Less and you look like a fat dentist on a Serotta who should be at the driving range instead of on a hot carbon race bike. That's my view anyway.

Check out "Adam Hansen's Ridley" for a bike that's looking a little extereme.

alihisgreat

FransJacques wrote:

Every seatpost has a limit on it. That plus 4-6mm is how high you can go.

More seatpost looks better to me, my bikes have 79.5cms BB to Saddle Top and I like to show lots of post. From seat collar to saddle rail on my 2 best bikes is about 20cms. Less and you look like a fat dentist on a Serotta who should be at the driving range instead of on a hot carbon race bike. That's my view anyway.

Check out "Adam Hansen's Ridley" for a bike that's looking a little extereme.

:shock: