# Would these frame numbers work for a 27.5 conversion?



## Fred Smedley (Feb 28, 2006)

I have a 19" Redline 55 elevated stay bike with tons of room for 27.5 wheels. 

1. HA 71
2.SA 73
3.Front center 655mm 
4.Chain stay length 420mm- FC and CSL were measured off floor from a dropped string. 
5.BB drop is 40mm as far as I can tell and I get a 11 7/8" BB height with 26" WTB 2.25 motorapters. 

I do not know the rigid fork rake but I am guessing 45mm as it steers fairly quick. 
Intended use is mostly smooth tight singletrack with some technical mostly intermediate type riding. 

I am asking over here instead of the 650B forum as this frame is kinda short in the rear and long on the front compared to most. As is the frame works pretty good with 26" wheels.


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## Live Wire (Aug 27, 2007)

None of the measurements you gave will help in answering your question!
Most 650b tires have a 35cm radius, so If you measure 35cm from your axle center do you have enough room for a 50mm+ tire to clear?

Just reread your post, are you asking if your frame geometry lends itself to the bigger wheels? I'd say yes, especially if you like a higher BB.


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## Walt (Jan 23, 2004)

Do it. Your BB is on the low side anyway and won't end up much (half an inch) higher. You have nothing to lose, IMO.

-Walt


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## Fred Smedley (Feb 28, 2006)

Walt said:


> Do it. Your BB is on the low side anyway and won't end up much (half an inch) higher. You have nothing to lose, IMO.
> 
> -Walt


Thanks Walt! I was hoping you would reply. I wanted to see how I liked the wheel size before going all in, I would only need to buy spokes, rims and tires to make this work so if I don't like the results I would not get killed on a big loss.


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## Fred Smedley (Feb 28, 2006)

Live Wire said:


> None of the measurements you gave will help in answering your question!
> Most 650b tires have a 35cm radius, so If you measure 35cm from your axle center do you have enough room for a 50mm+ tire to clear?
> 
> Just reread your post, are you asking if your frame geometry lends itself to the bigger wheels? I'd say yes, especially if you like a higher BB.


I do not especially want a high BB , I was more concerned about the F/C chain-stay length and how the bike would handle with those odd numbers and larger wheels.


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## Eric Malcolm (Dec 18, 2011)

Fred

Your bike is not too radical. It will work fine. 

I have 405mm C/S and 665mm F/C and I agree, it works good on 26". I also ride another wheelset with 700 x 35c CX tyres that match the 27.5" dia, and will say that the rolling and higher BB give the bike a more comfortable feel and it slows the steering just slightly. The biggest thing that I notice with a very short C/S is that when riding over fine pea gravel, the rear can step out a little bit quicker on a corner, but you adjust to that fairly soon!

I would expect that you would not really notice too much of a difference and that any change would enhance your ride. This is a change that I will look to do in the future on my own bike.

Eric


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