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Feet back and spread 'em!
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Discussion Starter · #1 ·
What is the optimum BB drop for a 29er?
The rig has 50mm, KM = 68mm,
I've seen up to 75mm on other 29ers.

I've read a few comments on this forum saying the KM BB is too low and they get a lot of pedal strikes. Any similar reports from Rig owners?
 

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bikecop said:
What is the optimum BB drop for a 29er?
The rig has 50mm, KM = 68mm,
I've seen up to 75mm on other 29ers.

I've read a few comments on this forum saying the KM BB is too low and they get a lot of pedal strikes. Any similar reports from Rig owners?
I found the BB on a KM higher than my Fisher. Plus, I've ridden some really rocky areas and never really found pedal strikes to be an issue. Just need to learn when to pedal and when not to.
 

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A few comments yes, on LOTS of KM's. All depends on the terrain you ride of course. I think you'll have to ride really technical rock gardens to get pedal strikes on a Rig with the BB in the highest position, with 175mm cranks. My '02 Fisher has 70+mm BB drop, and does see me hit stuff with my 180's every once in while. It does fly downhill though, that's always the tradeoff : stability vs. clearance. I know a pro downhiller that likes his pedals practically shaving the ground. He just times his pedal strokes.
Think of it this way : if you raise the BB a slight bit over say 70mm drop, you lose all the almost-misses, and are left with the rare full strikes. You don't need to have the BB way up there to prevent continious hits. All depending again on your terrain and riding style. Anyone should be able to find a sweetspot between 50 and 70mm, maybe 1% of riders would prefer it outside that range.
 

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Feet back and spread 'em!
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Discussion Starter · #4 ·
what led me to ask was considering a 26er for 29er conversion, specifically, the IRO Mia
http://www.irocycle.com/
It's a rigid steel SS with discs, and pretty cheap, $579, and looks like lotsa clearance under the fork crown and around the back tire....so I called them and Tony (I think it was) said sure a 29er will fit and that's how he has his setup. Will he sell me a complete Mia 29er for the same low price...Sure!! HMMMMMM. I'm a thinkin' hard now. but the rub comes when you look at standover and BB drop. for minimal standover clearance I would need a size 18, smaller than I usually go, and BB drop is 25mm, so I'd be an inch to inch and a half higher in the air than with a Rig or monkey...not good for climbing or descending. But that price!!! Dang!. If I didn't have 29er fever I could wait cause IRO is thinking about making a 29er specific SS next year. Maybe if we show enough interest he'll bump it up to next month.
 
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