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Discussion Starter · #1 ·
So I about 3 months ago, I replaced my BB pivot bearings because of failure. Today I took my frame apart to re-grease the contact points, and just clean the bike up. When I removed the BB pivot, the front two bearings had failed to the point of coming apart(again). Both time this has happened (both in less then a year) it was the front(closest to the BB). Since this is obviously a common problem, I was wondering if it was the front bearings that failed for everyone else as well? Of course, the enduro max bearings unavailable everywhere(didnt seem to make much of a difference for me anyway), so Im stuck with getting standard bearings of not riding. So I choose standard bearings this time.

Anyway, if people can chime in with what bearings (front or back) failed for them, and any fixes they have found that helped(other then enduro max bearings), I would appreciate it.
 

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Hey there mullen, it seems us freedrive owners who actually ride hard will forever be cursed with this problem.
here ya go. enduromax bearings.

http://www.ride-this.com/index.php/abi-enduromax-cart-bearing-688-8x16x5.html?source=googleps

and here

http://www.airbomb.com/ItemMatrix.a...utm_medium=GoogleProduct&utm_campaign=Froogle

I don't recall which bearings failed first on my frame that well. The next set are due to be installed sometime this spring... i remember having to remove the outer race with great difficulty as it had separated from the inner race and ball bearings spilled out as soon as i backed the bolts out. the inner race had actually fractured down the center splitting into 2 separate rings... this happened on the swing arm drive side, and BB non-drive side if i remember correctly.

So, options to figure out a better solution...

There are ceramic all ball internal bearing options, however, some of them cost in excess of 20 dollars a piece, 80 bucks for an experimental bearing useage is a bit excessive.
There are older bikes that use a metal on metal bushing. I've concidered looking into materials that could be machined into a proper bushing for the BB pivot. If this becomes something i begin actually looking to fabricate, I'll let you know, and see if you want a set.

beyond a bushing, rather than a bearing, i do not have the slightest clue what we can do to rectify the undersized bearing issue, except stock up, and get used to rebuilding your pivots on a 3 month schedual. I find large helpings of grease help keep things quiet for a little longer. I also added nylon washers to the BB pivot. i inserted one in between the BB link and the spacer to take up the slack, and not compress the tabs on the frame to eliminate the slack. I added the nylon washers on the outside of the bearings as well. I hope that reducing the metal to metal contact will help quiet the link down. so far its worked. we will see for how long.
 

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Discussion Starter · #3 ·
Those bearing are not in stock. If you click add to cart, it says they are unavailable. I have been talking to mongoose about a warranty claim. They gave me a new BB linkage:skep: I dont see how that will help anything but whatever, I will toss it on and give it a try.

I spent two hours getting the cage out of the BB side. so I guess it doesnt matter if its front or back.
 

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Discussion Starter · #4 ·
After talking to Mongoose more, They claim the improper torque on the bolts can cause premature failure. To tight puts extra stress on the inner cage and to little allows slight play that tears them apart. Just a light snug (105 in-lbs) is what is needed. I was using the correct torque specs, but they claim a strong lock tite must be used to keep the bolts from coming loose from use. I Think this is where I have my problem. We will see how long the non enduro max bearings I put in today last with the info given.
 

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When I clicked add to cart it said they would ship out to me in 5 to 7 days. They normally have to order them from a supplier, so it shows as "available" rather than "in stock"
You could also check with your LBS to see if they can order them.

Improper torque makes sense. Perfect sense. However, when the BB link mounting tabs allow for about 1 mm of play, it changes things. I am going to have to machine custom spacers, use red loctite, and not overtighten.... I am not the biggest fan of mongoose right now. Did you call and talk to a tech specialist?
 

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Discussion Starter · #6 ·
Iridethedirt said:
When I clicked add to cart it said they would ship out to me in 5 to 7 days. They normally have to order them from a supplier, so it shows as "available" rather than "in stock"
You could also check with your LBS to see if they can order them.

Improper torque makes sense. Perfect sense. However, when the BB link mounting tabs allow for about 1 mm of play, it changes things. I am going to have to machine custom spacers, use red loctite, and not overtighten.... I am not the biggest fan of mongoose right now. Did you call and talk to a tech specialist?
I was emailing back and forth with a tech guy. Im not a fan of mongoose right now either. If my bearings start lasting longer this time, I might start to sway back slightly, but my next bike wont be a Mongoose. I got it all back together, so only time will tell. Anymore, I would be happy with only rebuilding twice a year.
 

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PM me the email address if you dont mind... most of my attempts to contact mongoose end in frustration, not a response!

My take on owning this bike is, it will be my ride for another couple seasons most likely, while i save up, and decide what frame i want next. The Khyber fell into my lap, and was purchased for the cheap price of only 250 with rear shock (Xfusion 02RL Dual Chamber) and headset. it was a massive upgrade from my target frame (upgraded heavily, almost nothing left stock) i was riding just to be back out there on the trails, as i was returning from a long pause on the sport, and was impatient to wait for a good deal on a used bike. so, here i am, with a mongoose khyber that rides really nicely, if not a little on the sluggish side compared to a couple other bikes I've ridden, even an 05 spec. enduro felt like it had far less pedal resistance.
I honestly enjoy maintaining my bike, and learning what noises come from where and how to eliminate them. what i dont enjoy is that i cannot easily buy replacement wear and tear components. that the spacing on the BB link tabs is too wide, so the only way to eliminate play is to overtighten the bolts. like i mentioned before, i have added a nylon washer to eliminate the need to compress/bend the BB link tabs inward.

I would not run anything but enduromax bearings, and i think you'd be wise to obtain some asap, and check your BB link frequently, when they begin to index, replace them, the next step is failure, and prying the outer race from the frame, risking damaging the frame in the process.

what method do you use to knock out, and press in your new bearings? do you have a press??
I end up going ghetto and using light tapping on a socket w/extension to press out, and press in the new bearings. its ghetto, but works ok as long as you're super careful.
 

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Discussion Starter · #9 ·
Those bearing from tree fort are the ones I just purchased. We will see how long they last.

The "emailing" I was doing with mongoose was on facebook. They respond very quickly on facebook and pretty much never respond any other way.

As for removing and installing my bearings, I use a 8mm allen wrench and a hammer to tap them out. I then use a dremel tool with a buffing wheel to polish any imperfections out of the frame where the bearing seat. Then use the bolts to pull the bearings into place. I find it the easiest way to make sure they go in straight without putting extra stress on the frame.
 

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So after craking my ibex frame twice within a year, i decided to upgrade, hence purchasing a 09 teocali super. I ride pretty hard... usually taking the more technical trail if given the choice, i love all mountain and light freeride. Should i be at all concerned and is there anything i should check often or replace before things start going bad?
 

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Discussion Starter · #12 ·
XCkiller said:
So after craking my ibex frame twice within a year, i decided to upgrade, hence purchasing a 09 teocali super. I ride pretty hard... usually taking the more technical trail if given the choice, i love all mountain and light freeride. Should i be at all concerned and is there anything i should check often or replace before things start going bad?
If you do your own maintenance, order some 688 bearings to have on hand, and make sure you have a torque wrench that measures inch pounds. When you hear noises that sounds like BB that is creaking, its time to replace them.

Read this and follow it closely: http://www.mongoose.com/usa/usaeng/mtn/tech

Lastly, As stated above by Iridethedirt, it seems like the spacers between the bearings and linkage piece are to small, causing the need to over tighten them. adding a washer or making new spacers (which I am working on) to take up the slack will probably help.:thumbsup:
 

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Ok awesome! thanks for the help mullen, i wil definitley look into getting some of those 688 bearings:thumbsup: i am kinda regretting going with mongoose now:rolleyes:
 

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{Believeland}
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yeah i too love how the bike rides, especially on climbs, do you think you could put some pictures up of the spacers and your set up when it is all said and done?
 

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Discussion Starter · #16 ·
XCkiller said:
yeah i too love how the bike rides, especially on climbs, do you think you could put some pictures up of the spacers and your set up when it is all said and done?
I was just looking at your profile and saw that you live in cleveland, which is where I live as well. Right now my bike is being stored at Rays, So I haven't had my bike available to expierment. When I make them, I plan on making as many as I can to give out to a few people I know with the same problem. If I have enough, I will get you a set as well since you ride the same trails I do. :thumbsup: Since its pretty much winter, My motivation to make them fairly low.:yawn:
 

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Ah no way!! I rode at rays all last season, and i'm hoping to ride at least a few times over. maybe we can meet up and i can give you a hand with this little project.
 

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Here's an update on my Khyber, cross post from the thread I started, but I figure, it can't hurt.
So, as well all know, BB link tabs are too wide, or spacers are too skinny, or the design sucks because the tolerances required to keep this problem from happening are narrower than allowed by QC at mongoose. The solution is custom sized spacers it seems. I am willing, for now, to believe what mongoose told Mullen, that over tightening the bolts will cause the sideloading of a bearing not designed for that kind of stress, as well as allowing slop in the pivot, causing the bearings to fail.
Mullen, you said you had custom sized spacers fabricated for you by your dad on a lathe, and you said you used some aluminum bar stock.
Today i picked up a piece of 1/2 roundstock, 6061 T6 aluminum. I also asked a favor of some great guys at a shop i used to work for, and was told no problem at all, whenever i want.
If you want me to make you some spacers, let me know what sizes you need, and I will gladly make some in whatever size you give me to the best of my ability. it should be said, that while this is not a difficult task, I've not run a lathe in over 3 years. i have 3 feet of material though, haha, so i should have plenty of "practice runs" available if i need them. also i will keep anything i don't produce that isnt perfect for me, because it might be just what someone else needs. I plan on holding on to them for a long long time, so even if you've found this thread through some exhaustive google search for your mongoose bottom bracket pivot link on your mongoose freedrive mountain bike, and its the year 2015, send me a private message, and maybe I'll have what you need.

If anybody would like to take me up on making them some custom sized spacers, just send me a PM. Mullen, things still working well for you on your bike after you did as advised by mongoose, and also made spacers to eliminate slack? How long have then been running this way, and if you would do me the biggest favor, and remove your rear shock, and move the swingarm through its travel, and tell me how the bb link feels while it pivots... I'm very interested.
as a side note, i plan to do a time lapse of my rebuilding process of the bike, as well as the lathe process of making the spacers.
fun.
updates soon.
 
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