Bike Forums

Bike Forums (https://www.bikeforums.net/forum.php)
-   Classic & Vintage (https://www.bikeforums.net/classic-vintage/)
-   -   What era of MTB had the highest Bottom Brackets? Longest chain stays? (https://www.bikeforums.net/classic-vintage/1037854-what-era-mtb-had-highest-bottom-brackets-longest-chain-stays.html)

Pukeskywalker 11-10-15 08:48 AM

What era of MTB had the highest Bottom Brackets? Longest chain stays?
 
I want to use a set of 200mm cranks a touring bike, and I'm looking for a classic frame to start with.

Ideally I'd like it to be a rigid 26" MTB.

The problem with 200mm cranks is the risk of pedal-strike during a turn, AND heel strike when the heel of your shoe his the panniers behind you.

I have a modern 700c frame with a BB that is nearly 300mm off of the ground, but heel strike remains an issue.

Ideally the BB height would be something around 290mm or higher. Wheel size affects this - I'd be running semi-slick tires around 26 x 2.0" size

thumpism 11-10-15 09:22 AM

Earlier is better, back when the chainstays were nearly horizontal to the ground and there was enough room between the rear tire and seat tube for your boombox. Like this '86 Specialized from the "Saved" thread, although I'd have thought this frame configuration was over by then.
http://i26.photobucket.com/albums/c1.../image_23.jpeg

dddd 11-10-15 10:12 AM

200mm crankarms could do bad things to your knees.

thumpism 11-10-15 10:34 AM

1 Attachment(s)
While in Seattle I had the opportunity to ride a road bike with 215mm crankarms. This was on a custom (Bill Boston?) frame the guy had built to his specs and the chainstays sloped up from the rear axle to the BB. His whole deal was "crank circle" and this, by God, was his approach and solution to what he perceived to be the problem. Tremendous leverage on the cranks when riding but spinning was tough and it felt like I was hitting my chin with every revolution.

An '85 Cimarron like mine might be an equally good candidate for your project. I believe some earlier bikes like Diamond Back and Miyata might have even more pronounced BB clearance.
http://www.bikeforums.net/attachment...p;d=1423845254

John E 11-10-15 10:46 AM

2 Attachment(s)
My Schwinn has a pretty high BB and very long chainstays. As mentioned above, this is typical of the mid-1980s.

retrofit 11-10-15 06:04 PM

Look for an early Klein Pinnacle.

My 1988 56cm (22 in) Pinnacle has a 302.26 mm (11.9 in) BB height and a 430.53 (16.95 in.) chain stay length; 180mm crank length.

The smallest Pinnacle that year -- 46 cm (18 in) -- had a 292.1 mm (11.5 in) BB height with the same 430.53 mm chain stay length.

https://farm4.staticflickr.com/3925/...d527aebf_b.jpg

cyclotoine 11-10-15 06:24 PM

I agree, the early 1980s bikes tended to have higher bottom brackets and long chainstays. You might be able to do a 650 conversion with the right linear brakeset also to give you even more height?

Darth Lefty 11-10-15 07:29 PM

You could also look for a cyclocross bike. My XR800 compared to a CAAD3 road frame of the same size and year has about the same triangle but it's 17mm higher off the ground due to 9mm less BB drop and the rest from a bigger tire.

mobilemail 11-10-15 08:36 PM

I don't know about BB height, but the early 80s MTBs were so long you could ride in two counties at once!!!

wesmamyke 11-10-15 10:17 PM

Cannondale Beast of the East had a pretty high BB and longish stays. Though I think some of them had 24" rear wheels.

clubman 11-10-15 10:24 PM

Rocky Mountain Cirrus...good luck finding one.
http://fcdn.mtbr.com/attachments/roc...990-cirrus.jpg

Stratos was even prettier
http://www.retrobike.co.uk/forum/dow...e.php?id=53072

Pukeskywalker 11-10-15 11:36 PM

Thanks everybody for the replies. These all look awesome.

corwin1968 11-11-15 06:53 AM

1 Attachment(s)
My 1983 Takara Highlander had 47.5cm chainstays and a pretty high bottom bracket. Look for early-to-mid-80's bikes with "Repack" geometry. They will look like this:

http://img.photobucket.com/albums/v6...psquky7mbn.jpg


All times are GMT -6. The time now is 05:03 PM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.