BBS02 question, crank arm width ?

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rick (nova scotia)   10 mW

10 mW
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Joined: Mar 27 2014 8:15pm

BBS02 question, crank arm width ?

Post by rick (nova scotia) » Nov 24 2015 9:16pm

The crank arm width on a "normal" bike is about 5" from center of one crank to the center of the other, how much wider apart are they on the BBS02 ? Roughly will do, as I had one of those IGO's (for a day) with the weird mid drive, and it seemed the cranks were a lot wider than a stock bike.

Thanks, Rick

Jon NCal   1 kW

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Location: Mendocino, California

Re: BBS02 question, crank arm width ?

Post by Jon NCal » Nov 24 2015 10:16pm

Perhaps measure to the outside face of the crankarms, rather than the center, called Q factor, https://www.rivbike.com/kb_results.asp?ID=54

Dogboy1200   100 W

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Location: Maryland

Re: BBS02 question, crank arm width ?

Post by Dogboy1200 » Nov 24 2015 11:00pm

I'm currently in the process of replacing my BBS02 with a BBSHD and took some quick measurements. BBSO2 Q factor is 190mm but is about 12-13mm to the right of the center line of the bike. BBSHD Q factor is 200mm and is only slightly 2-3mm to the right of center line.
2007 Transition Preston FR BBS02 https://endless-sphere.com/forums/viewt ... 28&t=73635 Now HD https://endless-sphere.com/forums/viewt ... &start=225
2006 KTM 250 XC-W
2005 crf50 stunt bike
Oset 12.5 (son's bike)
PW50 (son's bike)
Mongoose Kids Fat Bike BBS02 https://endless-sphere.com/forums/viewt ... =6&t=84133 https://endless-sphere.com/forums/viewt ... e#p1232034

rick (nova scotia)   10 mW

10 mW
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Joined: Mar 27 2014 8:15pm

Re: BBS02 question, crank arm width ?

Post by rick (nova scotia) » Nov 25 2015 8:54am

Jon NCal wrote:Perhaps measure to the outside face of the crankarms, rather than the center, called Q factor, https://www.rivbike.com/kb_results.asp?ID=54
Thanks Jon, after 50 years learned something...Q factor.

rick (nova scotia)   10 mW

10 mW
Posts: 24
Joined: Mar 27 2014 8:15pm

Re: BBS02 question, crank arm width ?

Post by rick (nova scotia) » Nov 25 2015 9:01am

Dogboy1200 wrote:I'm currently in the process of replacing my BBS02 with a BBSHD and took some quick measurements. BBSO2 Q factor is 190mm but is about 12-13mm to the right of the center line of the bike. BBSHD Q factor is 200mm and is only slightly 2-3mm to the right of center line.
Thanks Dogboy for the measurements. I checked a couple of normal bikes, as they usually have bent, or splayed crank arms, the Q factor at the pedals is about 7 inches or 180 mm. I noticed that the crank arms that come with the kit are straight so the difference is small "around" 1/2" / 12mm. Pretty much a non-concern. As far as being right of center 12mm not too big a deal either, although ideally would be nice to maybe trim off the 12mm from the right side of BB, and add a spacer to the left. for a bit better chain line ?

I kind of figured this would be the "rough" amount as that is about the width of the final drive to the crank shaft.

Thanks again.

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