22T Granny Gear on Sofrider

fthills

Well-Known Member
Bottom bracket arrangent.

Hi Charles ,

As you know , I'm trying to fit a small chainring on the V . Just to compare could you post a pic of the bottom bracket arrangement on the sofrider, see if I can borrow some ideas.
 

Charles.Plager

Recumbent Quant
Hi,
It took me two attempts


Hi,

It took me two attempts to get this to work. The first one failed because the standard sqauare taper bottom braket was too short.
I ordered a wider square taper bottem bracket and then everything was groovy. The first post has some pictures. If you need more, let me know.

I alluded to this in my comments on your post. In the case of a square taper bottom bracket, there are two widths of interest. The width of the bottom bracket holder (i.e.,width of the frame holding the bottom bracket) and the width of the square tapers. In my case, there are very many bottom brackets that work with the same width of the frame but have the square pegs that stick out more, and that's exactly what I needed and found.

Most modern, higher end bottom brackets (and here is where I have virtually no experience), there seems to be only one width of interest. That makes what you are trying to do harder. I don't know if there's a high end enough crankset/square taper-like bottom bracket that would be reasonable to install on Vendetta.

When I got stuck, in addition to posting and getting help here, I also found posting at Bent Riders Online useful. In your case, I can even imagiine DF bike forums might have good ideas.

Good luck!
Charles
 

fthills

Well-Known Member
Thanks for that . The

Thanks for that . The vendetta uses a different arrangement. .The V needs to use an external bottom bracket, like this one.

http://chrisking.com/bottombracket

The chainstay has a locking mechanism that uses those external cups as a fixing point.
 
Dimensions: Shimano BB-UN26 Square taper Bottom Bracket?

What BB dimensions specification did you use successfully?

The link you provided for the Shimano BB-UN26 Square taper Bottom Bracket seems to offer a wide range of dimensions.
http://www.amazon.com/gp/product/B001G0T1JE/ref=wms_ohs_product

I think I need to upgrade my Sofrider double chainring to a triple as you have, as I have to face some steep hills, and consider loaded touring needs too.

Thanks.
 

Charles.Plager

Recumbent Quant
Hi,
I bought the Shimano


Hi,

I bought the Shimano BB-UN26 cartridge BB, JIS - 68x123mm. If I had to do it again, I'd spend $5 more:
http://www.amazon.com/Shimano-Square-Taper-Bottom-Bracket/dp/B0068FVOEM/ref=pd_sbs_sg_1
(I haven't had any problems with mine, but for $5, upgrading seems reasonable).

Cheers,
Charles

p.s. I used this crankset. It's on the heavy side, but the cogs are replaceable. I found it make a very large difference (triple to double).
 

Doug Burton

Zen MBB Master
Granny ring

There is currently only one triple crank the granny ring for which will clear the Vendetta chain stay clamps - the Shimano Ultegra triple.

It clears because the granny ring bolt circle is 92mm in diameter. All other road triples I am aware of use a 74mm granny ring bolt circle, which will interfere with the chain stay clamps.

Additionally, the Ultegra granny ring has tabs pointing toward the BB to keep the chain from becoming trapped between the BB shell and the chainring on chain drop. These have to be removed for the Ultegra granny gear to clear on Vendetta. On component sets we provide, we remove these tabs for you prior to shipping.

We are willing to accept this to maintain the exceptional rigidity that the wide chain stay clamps provide, and the resulting power transfer efficiency.

Cheers,

Doug
 

fthills

Well-Known Member
Thanks Doug   ,    Excellent

Thanks Doug , Excellent piece of information re the granny gear on the V.
 
Charles,
Did you keep your


Charles,

Did you keep your original 160mm crank arms from your Sofrider, or did you choose the 170-175mm cranks on your new Shimano crankset? Thanks.
 

Charles.Plager

Recumbent Quant
Hi,
I went with 170mm cranks.


Hi,

I went with 170mm cranks. I specifically tried to avoid 175 because I thought the jump would be too much.

I didn't really notice a difference between the original 160s and the new 170s. My guess is that I would have no issues with 175s either.

Cheers,
Charles
 
Charles,
I'm interested in


Charles,

I'm interested in following your suggestion to use the aluminum Shimano BB-UN55 bottom bracket, instead of the plastic BB-UN26 you used.

The two bottom brackets apparently only differ very slightly in dimension. You chose the 68x123mm BB-UN26, but the closest fit for the BB-UN55 is 68x122.5mm. Also, Shimano docs only mention the BB-UN26 as being the matching compatible bottom bracket for the Shimano Alivio M411 Hybrid Crankset you used.

http://www.amazon.com/gp/product/B004V25ZRQ/ref=wms_ohs_product
http://techdocs.shimano.com/media/techdocs/content/cycle/SI/Alivio-Acera/SI_0094A/SI-0094A-001-ENG_v1_m56577569830667768.PDF


http://www.amazon.com/gp/product/B005DTIEZQ/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

I'd think that 0.5 mm difference in width shouldn't be a problem.
 

Charles.Plager

Recumbent Quant
Hi,
I just went out and


Hi,

I just went out and looked at my bike and I agree that 0.5mm doesn't look like it will make any difference at all. I haven't had any problems at all with the bottom bracket I did install, but for the small difference in price, it looks to me like it would be worth doing.

I am quite happy with the Alvio crankset I used and would use it again. It's a little heavy but so is everything else on the bike, but the fact that you can swap out the cogs has been very useful. If you are willing to go to 175mm cranks, you have a few more options.

Let us know what you decide to do and how it goes.

Cheers,
Charles
 
Shimano worldwide parts ubiquity

Charles,

I consider the Sofrider a utilitarian bike, and have thoughts of long distance touring, possibly in remote regions. As such, the choice of Shimano parts, such as this Alvio crankset, will hopefully offer me better probability of finding compatible replacement parts such as the chainring(s). What extra options would I have by going with 175mm cranks?

Cheers,
Horhay
 

Charles.Plager

Recumbent Quant
Hi Horhay,
If I remember


Hi Horhay,

If I remember correctly, there were a fair number of SRAM/Truvativ/etc choices with 175 mm cranks (for example).

I like the Alvio crankset and don't see any reasons to not go with it.

Cheers,
Charles
 
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