Frame sizing - Rules ???

[Broox]

I used to work as a salesperson at a bike store in the early 90s. The staff at the store had a few general rules to size people to mountain bikes. We first made sure that customers had 2-3 inches of space between their crotch and the top tube when they were straddling the frame. When they were on the bike in a comfortable position, we usually wanted the handblebars to block their view of the front hub. And of course they needed to have a slight, comfortable bend in their elbows as they gripped the handlbebars while riding,

For whatever it is worth...

 

[mimbresman]

what is the horizontal top tube length of a 16.5 Merlin and what is the maximum length of stem you'd be happy with.

A 16.5" Merlin has a 22.38" top tube, 16.75" chain stays, 29.2" standover, 11.7" BB height, 4" head tube and a 71 degree head angle.

I don't like stems over 140mm really.

Do you reckon that would be too small for me?

My first post...We are the same size with the same inseam. I ride a 1996 Merlin MTN (straight gauge Ti). It is a "medium" which I think is a 17.5". I think a 16.5 might be too small. My frame as a TT length of about 22.75" I recently fit it with a 110mm Thomson stem and carbon fiber riser bars. I like the fit.

I say the 16.5" will be too small based on my wife's 1999 K-2 Zed. I don't fit on it very well. My butt hangs off the seat after a while.

In 2006 I bought a 2000 Litespeed Toccoa off the Internet. I had it retrofit with S & S couplings because I wanted a high performance travel bike but didn't want to hack my Merlin. The Toccoa is a 18". The TT length is also about 22.75". I refit the bike with a 110 mm stem and I like the fit better. This bike feels taller, but the saddle and BB are the same distance from the ground as the Merlin. It does have a SID fork, where the Merlin has a rigid Ritchey.

Both bikes are great, but I am starting to consider the Litespeed a super-bike. I believe it can out climb the Merlin. It is smoother riding (that might be due to the SID fork whereas the Merlin is rigid, but it also has slightly longer and bent chainstays). The Litespeed is super stable in descending and very precise in steering.

BTW the S & S retrofit has pretty much paid for itself in saved airline fees. It has flown from the USA to Venezuela (where I live and work) and back 4 times already, and from the USA to Scotland and back. Now considering a retrofit on the Merlin.

 

[andrewl]

I don't know, first he accuses me of obsessing, then all the points he makes are ones that confirm I was right.

Was only stirring you mate with the KK obsession comment

Yes agree with you that longer sus forks work less well with long stems too and was commenting on the bikes I ride and the places I ride.

I still don't don't like long stems on rigid bikes either for real techy stuff as they still put my weight too far forward in relation to the front axle and hence most of my old rigid frames are longer in the effective top tube. The only advantage with the rigid forks is that they remove the compression effect which is some repects is a redundant feature as most places where this is a problem for me a rigid bike would have seen me biting the dust well beforehand....