Frame Size - advice

ROK ON

Guys I need some advice on a frame size as I am in process of buying a new bike.

I can go for a small or medium frame and the shop has recommended the small. However the small is 10mm smaller than my present bike.
Here are the measurements;
Horizontal TT: measures 525 ( versus 535mm on my current bike).
Head tube length. 125mm on both bikes.
HT angle 73,5degrees on both bikes.
Wheelbase; 963.5mm versus 971 on current bike.

My query is; as I presently use a 535mm frame and 90mm stem will there be any disadvantages to a slightly smaller frame with a longer stem.
That is what are the downsides if riding a bike with a frame that is slightly too small.

thanks.

uberwolf

presuming this is road (my answer is more pertinent if it's a MTB) I understood the view was always that shorter stem gave you better control

Lumen

If the head tube is the same length, and you are using a longer stem, the handlebar height will be fractionally higher due to the stem rise.

So the bike is unlikely to feel smaller, from a comfort perspective.

I guess you might notice some differences in feel due to the shorter wheelbase and being further forward, but nothing you wouldn't adjust to.

You'll probably notice it most during fast descents - take care.

DirkVoodoo

Wheel-toe overlap, only really matters for tight maneuvering and commuting I have found.

blorg

Lumen wrote: »

If the head tube is the same length, and you are using a longer stem, the handlebar height will be fractionally higher due to the stem rise.

I noticed this swapping the stem on my cross bike from 90 to 120, the bars are now much higher. Of course presuming you had spacers under you can just drop them back down again; you can also get stems with a shallower angle.

The key issue then is the smaller wheelbase which I believe makes a bike twitchier and "racier," a longer wheelbase makes it more stable.

rottenhat

uberwolf wrote: »

presuming this is road (my answer is more pertinent if it's a MTB) I understood the view was always that shorter stem gave you better control

No, I think you have that backwards - longer stem gives more stable handling.

niceonetom

uberwolf wrote: »

presuming this is road (my answer is more pertinent if it's a MTB) I understood the view was always that shorter stem gave you better control

rottenhat wrote: »

No, I think you have that backwards - longer stem gives more stable handling.

You're both right. Short stem means sharper handling (flickable) and longer stem mean more stable in a straight line. It's a question of what you mean by "better".

A longer stem is way more euro pro. You'll struggle to find a rider with a stem below 120mm, a lot use 140 or more. That must be factored in too.

My bike is ~57cm TT equiveland and I use a 110mm stem. If I had a choice between a 56cm with 120mm stme or 58cm with 100mm stem I'd go for the smaller bike/longer stem combo. But I have a fairly aggressive riding possition (I'm fairly flexible and need all the help I can get against the wind). If I was looking at pure comfort i might go for the bigger frame...

ROK_ON have you considered that the smaller bike is likely to have a shorter head tube too? You sure you're not going to need a lot of spacers if you opt for the smaller bike.

ROK ON

Thanks. My biggest worry would be clipping the front wheel. While I am small my feet are not.

@Tom the headset on my Dolan and this bike are same. However if I go for next size up (540mm top tube) the headset would be larger and the wheelbase longer, but I would need a pretty small stem.
On spaces, as I have lost a little bit of bulk from midriff I have considered removing the two spacers on the Dolan to see how it feels.

I had thoughts that headset and tube length would answer the problem but reality is I am caught between 2sizes neither of which maybe ideal.

bbosco

ROK ON wrote: »

Thanks. My biggest worry would be clipping the front wheel. While I am small my feet are not.

I really wouldn't worry too much about this one. I have wheel-toe overlap on mine and it's not been in an issue in 2 years of riding it.

rottenhat

ROK ON wrote: »

I had thoughts that headset and tube length would answer the problem but reality is I am caught between 2sizes neither of which maybe ideal.

Save up and go custom. You know it makes sense.

blorg

bbosco wrote: »

I really wouldn't worry too much about this one. I have wheel-toe overlap on mine and it's not been in an issue in 2 years of riding it.

I have it on some of my bikes too (generally with mudguards) and while it is not a major problem if you CAN avoid it, it is certainly nicer.

Raam

rottenhat wrote: »

Save up and go custom. You know it makes sense.

Yeah, of to Viner with ya

DirkVoodoo

Yeah like I said it doesn't matter too much on the road or at sportives, you only really notice it pulling very hard turns at slow speed like when we take a wrong turn and everyone has to turn around, that kind of thing. Just remember to keep your feet at 6 and 12 when doing those turns. I have also knocked myself off at traffic lights by clipping a front race blade on my commuter.

bbosco

I was a bit surprised and disappointed at first when I realised mine had overlap, given that it was custom-built.
I emailed the framebuilder later on and asked him about it and he said it was unavoidable given the other parameters that went into the design. He had asked for my shoe size among the many other measurements, so I'm sure he took it into account.
This blog would seem to back him up :
http://davesbikeblog.squarespace.com/blog/2006/11/5/toe-overlap-no-problem.html

rottenhat

bbosco wrote: »

I was a bit surprised and disappointed at first when I realised mine had overlap, given that it was custom-built.
I emailed the framebuilder later on and asked him about it and he said it was unavoidable given the other parameters that went into the design. He had asked for my shoe size among the many other measurements, so I'm sure he took it into account.
This blog would seem to back him up :
http://davesbikeblog.squarespace.com/blog/2006/11/5/toe-overlap-no-problem.html

Yep, it's pretty much a fact of life for the shorter cyclist - it's that or mess unacceptably with the geometry of the bike. I think pretty much every road bike I've had has had some measure of it.

Who built your frame?

ROK ON

Ok. Bike ordered. Going for medium not small. Longer head tube may mean better comfort and lessen need for spacers. Will try a short stem.
Wheelbase on themedium is same size as Dolan. So a compromise.
I am hoping that I don't have Lumenesque problems - loads of ill-fitting bikes.

Am so excited. This is the best looking frame I have seen that approaches a suitable geometry. Also the BB is huge, which u have admired for a long while.

Would love a Viner, but just can't afford it right now.

Raam

ROK ON wrote: »

Ok. Bike ordered. Going for medium not small. Longer head tube may mean better comfort and lessen need for spacers. Will try a short stem.
Wheelbase on themedium is same size as Dolan. So a compromise.
I am hoping that I don't have Lumenesque problems - loads of ill-fitting bikes.

Am so excited. This is the best looking frame I have seen that approaches a suitable geometry. Also the BB is huge, which u have admired for a long while.

Would love a Viner, but just can't afford it right now.

Whatcha go for again?

lescol

I'm intrigued at this stage ROK ON! What's the bike?

bbosco

ROK ON wrote: »

Ok. Bike ordered. Going for medium not small. Longer head tube may mean better comfort and lessen need for spacers. Will try a short stem.
Wheelbase on themedium is same size as Dolan. So a compromise.
I am hoping that I don't have Lumenesque problems - loads of ill-fitting bikes.

Am so excited. This is the best looking frame I have seen that approaches a suitable geometry. Also the BB is huge, which u have admired for a long while.

Would love a Viner, but just can't afford it right now.

Congratulations! What did you get?

rottenhat wrote: »

Who built your frame?

I got it through a small shop in Celle Ligure, Italy, called Officina Girardi. I got in touch with them initially because they were the only place I could find online that sold a particular Olmo frame I wanted (the Olmo factory is in the same town). Sig. Girardi persuaded me to consider one of his own custom steel frames instead. Their website disappeared about a year ago unfortunately.

ROK ON

www.kuota.it

Getting Kebel in Black with silver finish.
Ultegra SL.
Wheels. Tbd.

Similar to the Tom that Roche will be riding this year but more mid range than top end.
Came down to Roubaix, 2 different Felts and this. This won on looks and geometry.

niceonetom

ROK ON wrote: »

Similar to the Tom that Roche will be riding this year...

:eek:

Raam

niceonetom wrote: »

:eek:

he means Kom