If you can stand it - one more request for sizing advice

Ricky_M

Just bought a Boardman CX in Large but having second thoughts - is Medium more correct. Would welcome your advice.

I'm just over 6ft (183cm) and have about an inch clearance over the TT when standing on the Large BUT the saddle has to be pulled forward up to the max limit and I still feel like I'm over-stretched to the hoods. Flipping the stem doesn't resolve the problem and not keen on reducing the stem length for impact on steering and seat would still be maxed out to the front.

Medium, good couple of inches over the TT when standing and running couple of inches more seat post. Seat pushed well back but not quite maxed out. Feels like a more natural reach to the hoods but steeper angle of attack due to higher seat post.

I'm struggling to decide if I should switch to the medium. As a 6 footer I assumed a large would be right but tried it again and it does feel over-long. The medium feels like it could be right, but it's almost maxed out in the other direction and i'm more used to a more upright riding position. Am I trying to squeeze too much out of the medium frame or does that sound like the go?

Would welcome you knocking some sense into me... Cheers.

mfin

Look up if the seat tube angle is the same on medium and large.

The first part of bike fit regarless of if the bars are 5cm or 40ft away from you, is to get your fore aft seat position correct (knee over pedal axle when forward - look this up).

If the seat tube angles are the same on Medium and Large then your seat would have to be in the same place on its rails... only then can you look at the reach to your bars and the height of them by looking at different frame sizes, stem lengths, stem spacers.

Buying a bike and putting your saddle in the wrong position fore/aft to compensate for a frame size is a completely wrong thing to do.

...if you're moving saddles like this I dont thik it sounds like you understand bike fit rough principles, so the single best bit of advice is to go for a bike fit.

foggymike

You might just need a 1cm shorter stem (which will make almost no difference to handling, honestly!). How long is your current stem anyway?

Also, have you tried moving the shifters back on the bars a bit if that's where you usually hold? Different bars have different reach and drop measurements so that's something else to consider - lots of things you can play with!

Perhaps best to post a pic of you on it as it's pretty hard to advise otherwise I'm afraid.

Ricky_M

mfin wrote:

Look up if the seat tube angle is the same on medium and large.

The first part of bike fit regarless of if the bars are 5cm or 40ft away from you, is to get your fore aft seat position correct (knee over pedal axle when forward - look this up).

If the seat tube angles are the same on Medium and Large then your seat would have to be in the same place on its rails... only then can you look at the reach to your bars and the height of them by looking at different frame sizes, stem lengths, stem spacers.

Buying a bike and putting your saddle in the wrong position fore/aft to compensate for a frame size is a completely wrong thing to do.

...if you're moving saddles like this I dont thik it sounds like you understand bike fit rough principles, so the single best bit of advice is to go for a bike fit.

Thanks for this, it's the first time i've tried to get everything right on a bike and the whole process is doing my head in tbh. Trying to consider all aspects but evidently every bike has different sizing pros and cons - eventually took the plunge more out of exasperation than anything else. I'll go back to basics as you suggest and see what comes out of the process.

Ricky_M

foggymike wrote:

You might just need a 1cm shorter stem (which will make almost no difference to handling, honestly!). How long is your current stem anyway?

Also, have you tried moving the shifters back on the bars a bit if that's where you usually hold? Different bars have different reach and drop measurements so that's something else to consider - lots of things you can play with!

Perhaps best to post a pic of you on it as it's pretty hard to advise otherwise I'm afraid.

Thanks - that's very helpful. I was concerned there would be a dramatic impact on the steering with stem reduction so perhaps it's not such a big deal. Also trying to keep costs down by not having to swap out parts immediately after buying but maybe that perfect world doesn't exist!

sloppyschleckonds

The effective top tubes of the boardmans are slightly longer than others. If you went down a size you could find you would need a longer stem than standard. Go too big a frame and it will feel like you are riding a lump of wood.