# Anyone using Truvativ BB-conversion kit?



## PiroChu (Apr 8, 2004)

Hi folks,

Anyone here using the Truvativ BB-conversion kit? Any issues with installation and/or riding/durability? Currently I'm looking at an used/older Mongoose Ritual frame that has a larger American BB shell, and I want to use a MTB crankset (ie. FSA Gap) on it with the use of this Truvativ kit. So, I have a few questions, please.

Q#1: I see that the center surface of this kit where BB would sit against is a bit recessed in. Is that so that it _effectively _keeps the original shell width, right? (Meaning, if a frame BB shell is 68mm, then it'll effectively remain as 68mm, not effectively becoming wider as 73mm with extra width from the kit/adapter.)

Q#2: Once pressed in, can this kit be used with external-type BB (eg. Hollowtech), or only with internal-type BB (eg. Octalink)? Hoping that the recessed surface area of the kit is large enough for external-type so that BB sits flush against/within the flat recessed surface, not on the sloped surface of the kit. (I think the shoulder of both BB types should be the same size anyway?)

Q#3: I'm assuming that this press-in adapter sturdily stays put against the torquing of BB? (Not gonna slip & spin around in shell?) Should I lightly grease it before pressing in (just like a headset), or go raw/dry (so not to slip/spin around)?

And any other tips, like "_just be careful when..._" sorta things that I should know, if any.

Thanks for the info in advance.
- PiroChu

 
"Installation Note: Press in right side (left threaded) bushing first. Then draw in left side bushing by gradually tightening the allen head bolts. The bolts go through the left side and screw into the right side adapter."


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## GTscoob (Apr 27, 2009)

Looks similar enough to a BB30 adapter kit. 

I would lightly grease the cups and use a headset press, or DIY with a threaded rod and some large washers. Grease/antiseize on the three bolts so they turn easier and more evenly. 

Should work great with an external bottom bracket, at least the similar BB30 kits do. If you are running a converted crank with granny ring tabs, you might need to dremel the tabs off for clearance. 

It shouldnt spin around in the case that the bearings in the bottom bracket seize but you should know they're on their way out well beforehand.


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## PiroChu (Apr 8, 2004)

I greased everything, and just finished installing the cups/bolts now. Everything went very smoothly (without any surprises along the way). :thumbsup:

PS.
Here are some minor notes...

The package doesn't come with an instruction, and the cups are not marked as "left" & "right", either. But you can easily tell by (A) tracing the thread with a finger nail to see if it's the regular threaded (left side) or reverse threaded (drive side), or (B) following the helpful 'installation note' from Harris Cyclery.



> Installation Note:
> 
> Press in right side (left threaded) bushing first.
> Then draw in left side bushing by gradually tightening
> the allen head bolts. The bolts go through the left side and screw into the right side adaptor.


Basically, in this pic below, you're looking at the left-side cup (with heads of the 3 bolts being visible).



The first (drive side) cup went in easily with a headset tool. Then, when installing the second (non-drive side) cup, initially the bolt tips won't quite reach the holes in the already-installed first (drive-side) cup. So, aligning the 3 bolts/holes, I pressed in the left cup a tiny bit (with a headset tool, while being careful with the bolt alignment so not to damage 'em) just so that the first few threads engaged. After that, I just tightened the 3 bolts gradually/evenly to draw in the 2nd cup.


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