tedder987

On my 2017 Spz Roubaix (the first FS version) it has a Praxis Zayante crank and their M30 bottom bracket. I just had my second BB fail and was wondering if others were also having this problem. What is happening is the bearing race is breaking. Both times this has been at the bottom on the non-drive side. The First BB lasted 9200 miles and the second only about 4300 miles. I am a biggish guy (~6'3", 205lbs) and live in an area with a lot of climbing so I suspect I am harder on this part than most but still...

So have others been seeing a similar failure with Praxis BB's or is it just bad luck that I keep breaking them the same way.

sdmc530

I got a good chunk of weight on you and have never had any issues. I have praxis bb on two of my bikes and they are both running perfect after a few years.

Sorry...Have you reached out to Praxis CS yet?

tedder987

@sdmc530, it honestly hadn't occurred to me to contact their customer support. Have done so now though, thanks for the reminder. If I hear anything back from them I'll add it to the thread.

tedder987

@sdmc530, thanks for the suggestion. Apparently what we are looking at is the circlip that holds the bearings not a broken bearing race. The support tech suggested just tightening it up a bit to eliminate the creak that got me here. I have also learned that not all the mechanics at my LBS are created equal (I know, should have been obvious) so I'll try to tighten the bearing up a bit this weekend as the praxis support suggested...

sdmc530

Yeah not all LBS mechs are the same. I think the torque setting on a praxis bb is 48-55 nm if I remember correctly but that is on a bsa threaded that is what have. I have had excellent luck with them. I do have a slight creek on one of mine but its nothing I get excited about.

I like praxis stuff I guess, works for me and they have excellent CS when I have needed them.

tedder987

the 48-55 is definitely the torque setting for the 8mm hex that holds the crank (did it last weekend) so it might match that for the cups. This is the english threaded (BSA) M30 also. This creak came on pretty suddenly 2 weeks ago and is really loud. Enough so that if tightening doesn't work I'll swap in the new BB anyway. Compared to the shimano BB I had on my old giant defy its been a lot quieter generally.

Also turns out you can replace just the bearings ($22) and not the whole BB ($45) which will be the plan next time I have to do so.

smashndash

I don’t think Praxis bearings are the best in the world. I think they use Enduro, which are meh. Praxis (sneakily) use a custom NDS bearing with a built-in 2mm reducer, but besides that the bearings are standard 6806. If you can get your hands on a 2mm reducer from Kogel or maybe Hambini, you can just use any 6806 bearings you want. This means you can get top end bearings from someone like NTN and choose between full contact (durable) or contactless (fast) seals. It’s simpler to go with the praxis kit, of course, but I personally would be bothered if there were exactly *one* option available for one of my wear items.

sdmc530

One thing to remember is if you have a praxis crank set you have to use their bearings because of the M30 design they have. If you wanted to change bearings not a big deal in itself but then you would need new cranks or a conversion kit for the cranks like you stated there is a 2mm reducer BUT the cranks are not 30mm across. They are 30mm on side and 28mm on the other.

BUT your spot on about one option for wear items only being available from one place, that is how your market your product 101


I don't know where praxis is on the level of quality but I don't think they are bad. I am sure they are not the greatest on the market but I have no complaints I guess. I have them on 2 bikes and do me fine.

sdmc530

Yep, for that cheap its not bad at all. I do have an extra BB in my tool box though just in case. I have OCD about stuff like that!

tedder987

Final update for the archives, the torque setting for the BB itself is 40 Nm