fitting a 68mm thun torque sensor to pf/bb 30 system?

emaayan

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one of things that always got in the way of selecting a frame was the bb shell of most frames is not 68 and not even threaded, while i still want to keep my 68mm bb thun torque sensor active, i was wondering if anyone tried it with adapters such as these:

http://www.chainreactioncycles.com/il/en/fsa-bb30-threaded-adapter-b3119-/rp-prod129935
http://www.chainreactioncycles.com/il/en/fsa-pf30-threaded-adapter-b3167-/rp-prod129936


additionally can ISCG tags interfere with mid-drives mounting?
 
More than one Bicycle Mechanic has told me that those press in BB30/PF30 to Threaded BSA adaptors do not work much,
the one that is recommended is the Praxis Works Conversion BB, reading about it shows why.

https://praxiscycles.com/conversion-bb/
 
ScooterMan101 said:
More than one Bicycle Mechanic has told me that those press in BB30/PF30 to Threaded BSA adaptors do not work much,
the one that is recommended is the Praxis Works Conversion BB, reading about it shows why.

https://praxiscycles.com/conversion-bb/

That's for outboard bearing cranks, but the Thun BB is a square taper cartridge and won't work with the adapter you mention. It has to use BSA frame threads. Regular press fit threaded cups will work, but should be installed with cylindrical fit Loctite for best results.
 
you mean replace the cups on the thun with pressfit ones?
 
You are right,
My Mistake.
>

The one he linked to from FSA , I have been told, has a tenancy to rotate inside the frame.
>
Chalo said:
ScooterMan101 said:
More than one Bicycle Mechanic has told me that those press in BB30/PF30 to Threaded BSA adaptors do not work much,
the one that is recommended is the Praxis Works Conversion BB, reading about it shows why.

https://praxiscycles.com/conversion-bb/

That's for outboard bearing cranks, but the Thun BB is a square taper cartridge and won't work with the adapter you mention. It has to use BSA frame threads. Regular press fit threaded cups will work, but should be installed with cylindrical fit Loctite for best results.
 
No, I forgot that the Thun was a torque sensing BB,

Since you are going to have to drill a hole in the Frame at the BB Shell in order to run the wires from the Thun BB out,
You could buy that FSA adaptor and drill a small hole or two into the BB shell as well to hold the adaptor in place with a screw or small bolt and nut. To keep it from rotating in the BB shell of the frame.



emaayan said:
you mean replace the cups on the thun with pressfit ones?
 
but i would still need a 68 mm shell right?

and i'm assuming i would need to drill a hole in the shell first fit first bb right?
 
No, you can buy a bike that has a 73 mm ( wide ) Bottom Bracket Shell.

Notice on the link that you posted on your first post, when you clink on that link to the FSA Adaptor notice that you have a selection , either order one 68 mm wide , or 73 mm wide.

Note that most all Mountain Bikes have a 73 mm BB shell width. ( unless they are Fat Wheel Mountain Bikes ) .
And most road bikes have a 68 mm wide shell. ( Most not all some Road/Gravel Bikes have a 73 mm wide shell )

Yes you would have to drill/dremmel a hole in the Bottom Bracket Shell because of the wires on the Thun BB.

I would also drill a hole or two through the BB shell on the frame and use a tap screw or two into the FSA Adapter , just enough to go through the frame / BB Shell and into the Adapter to keep it from rotating in the frame.

The cheaper the bike the chances are higher that the BB 30/ PF 30 shell was not machined with enough precision to keep the Adapter from rotating . ( this was the only problem with BB 30 / PF 30 and other Press Fit systems , the Frame in Manafacture, ... Not ! the BB Bearings or Crankset )

Bike Companies like Specialized are now only offering a BB30 Frame on their Higher End Bicycles, but only offering the older threaded BSA BB on the lower end models .






emaayan said:
but i would still need a 68 mm shell right?

and i'm assuming i would need to drill a hole in the shell first fit first bb right?
 
ah, but that would mean i would need 68mm into a 73 shell, i've done some googling on that http://www.bikeradar.com/forums/viewtopic.php?t=12567613 and the result are ...worrying, and considering that it's gonna be a mid-drive it's all the more pressure on the drive side.
 
?

Why would you have to do that, since the FSA Adaptor comes in either a 68 wide or 73 mm wide.

Does the Grin Technologies Thun BB , Only , come in a 68 mm width ?

We really should know

1 ) What Bike frame, Make and model and year .
and
2) What mid - drive you are going to put on it .
 
i'm gonna use my modified gng 2015 mid-drive on it, it's own brackets are 68 mm wide, so that's once restriction , and yes, ALL grin's bb's (thun, NCTE, TDCM) are 68mm, so that's another restriction, so far the frame i've aiming for is https://ritcheylogic.com/p-29er-frame-black-yellow (i've posted another thread about it a few hours ago) since it's the only frame i found of mountain bike which has a 68mm threaded shell.

and the reason i'm doing (it's rather a long story) is in case the welding on my current custom steel frame which developed a crack for the second time on the chain stay ( custom because when i ordered i saw no 29ers at all with 68mm shells).


if you're referring to a specific frame of 73mm there isn't a specific one, because i've passed along so quickly as soon as i saw they had 73 mm shell. (or pf30/bb30 one)
 
Strange that the Thun is only 68 mm . wonder what Grin says about this ?

Ritchey has always made good products, and if you are a big fan of the way a good steel frame rides, I understand, I have had good quality double butted and even triple butted cro-moly frames in the past.

Have you thought about taking a common frame with the 73 mm wide shell and have a Machinist shave off 2.5 or even 2 mm off each side ?

You could then have a full suspension bike.
 
no really, i'd need a machinist willing to do that accurately on the mm, and not mess up the threads. it's not like he can hold the frame somewhere... kind scared from it.

i was never really sure about the ride of alu vs steel, i have a trek 7700 with another gng with bust shaft bearing (which still works, but maks a horrible horrible sound) with a ridig fork , and that's hard to ride.

but i'm currently a fan of a frame that works

this is the original brake on the frame
AJAuFCY.jpg


and this is the 2n one
C51KGq6.jpg


and this is before i messed it up :)
you can see the ritchey one is rather similar (except ritchey's is tripple butted and this one is not i believe, and this one is 42 mm down tube, richey's sould be 24), but look at what richey has on the brake side.
UFUAXV7.jpg
 
Since you have not yet bought the Richey Frame, and you have a mid-drive you might want to look at Full Suspension Frames.
From what I have seen of Israel on the Travel Chanel/Travel Programs , If I lived there I would want a F.S. Bike.
There are F.S. frames for around the same price as the Richey frame. and many have BSA threaded BB's .

You would have the challenge of the 68 mm thun BB,
However

When people get frames with the old standard BSA threaded bottom bracket shells, it is always a good Idea to take the bike/frame to a bike shop and have them " Face " the bottom bracket threads / shell.

https://www.youtube.com/watch?v=N3jnxgey3wU

You can face the shell enough to take off a couple of mm's off each side, and as you can see in the video ,

BTW what does Grin say about the Thun, I am sure many people put it into a bike frame that has a 73 mm wide BB shell.
 
Grin said they don't have much of a problem with it, they looked into a few years ago.

Anyway while i was checking fs 29ers i suddenly stubmbled on to this , it seems to allready have a 68mm shell in it. , but it's made of carbon: (
http://www.cyclesfanatic.com/cf29fs-full-suspension-29er-frame
 
btw, the thing about facing the shell, is that a lot of frames are coming with ISCG 05 mounts which are at the edge
 
Are you saying that they said you can use the THUN on a bike with 73mm bb shell ?

That link for the cyclesfanatic is way too expensive, it looks just like a painted over Chinese FS Carbon Frame, and does not even come with a rear shock.
for just a little more you can get a whole bike that is FS.
or perhaps even less $
Some reading on Chinese Carbon Frames.
http://forums.mtbr.com/29er-bikes/chinese-carbon-29er-640919-94.html

emaayan said:
Grin said they don't have much of a problem with it, they looked into a few years ago.

Anyway while i was checking fs 29ers i suddenly stubmbled on to this , it seems to allready have a 68mm shell in it. , but it's made of carbon: (
http://www.cyclesfanatic.com/cf29fs-full-suspension-29er-frame
 
I am having the same Issue with my Santa Cruz full suspension frame.
One of the reasons I am waiting for more development on RC motor mid-drives.
The little TDSZ 2 looks good , but not much power, even though they are getting better about the U.S. market . I would perhaps have to cut off one of the 3 ISCG mounts . Since I don't plan on using that mount for a bash guard it is possible, but not the best for resale .
Have a close up of the bottom area where your cyclone is close to the frame ?

emaayan said:
btw, the thing about facing the shell, is that a lot of frames are coming with ISCG 05 mounts which are at the edge
 
i got over carbon, especially since i brake stuff.

186xMndy4sMINvkynuMWb8rX69NaGddCBURGg15jbCzaU2-_PB-_zEduKVoAWUbx42iUKklPrxi2ZwKHJm4Pr_7klWmm9-cy_db-TsAM20cUGjJsKyZH9iCjEC_2VFOB-32V-7M9J8ZovwuActUiDzWT_c9eZtZhbbTiDqFSAZfZN1I2gnItqEDSIybr5KHrdyqY59-g_jlCSFqV91WRZeI_Nx7i_-G7rUAMwnIKtkobSRbAsDLWjZvTlhWKYiVkjfKltPqfostGpa3IUuY1EG23IlbOE6wUdYqi_1m2we_jEiuw24hfuNVJMtpHSRupqx6oc_CzVvpmOu9jRoZSmDycPcn_IG-xWBM8i4-XZsITDM0Bfr6wkbb9w-tpfhdYcCmF17zX_YT2KdAwmSFhS7tDGrFXH0bsTKxl7WVAG-CfcixyKUnQuMLTchsBI1qTZv39mOVEDuQnsZ5CCeUOL3LhrRD-e13A_15RQun-HKlDoyHPPHjjHQYYpUBfQibeV7eHEzYcei8Y6lhPaPr0HZBf7wE3GOQI3USDfXnR6dmCYk1zhQGY6ZhfBcxa3ExetmFrYMLCDGBnU9uDkBsIrGew6VlA9RbhKH7S=w1287-h965-no

i don't have a cyclone, but a modified gng 2015


grin said i can use the pressfit adapters with the thun, nothing about 73mm.

i've been searching over FS bikes, but i don't see many, i can use, (or i'm not looking in the right place)
what i'm looking currently is something that has 68 (or for now 73 mm threaded)

doesn't have ISCG 05 mounts that could stop me from facing it

a 29er

135x10 spacing that would allow me to place an IGH (like an alfine 8 on it)

preferably with rear rack mounts

if it will have Full suspension, it needs to have space for a triangle battery, and the shocks mounts should not come close to the bb

meanwhile i found this hardtail which looks nice: http://carverbikes.com/frames/aluminum-gnarvester/

btw i've noticed many frames include post on the chain stay exactly where my frame broke.
 
I can see by the tubing , and weight that it would be a strong frame.

" meanwhile i found this hardtail which looks nice: http://carverbikes.com/frames/aluminum-gnarvester/ "

It does have a tapered head tube, which is good, as it is getting harder every month to find a good suspension front fork with straight head tube steerer.
There are always good deals on last years or the year before forks .

Interbike is happening now, so soon the 2017 Forks will go on sale.
 
i could never figure from frame specs if i could fit my current fork which is this one

https://www.bike24.com/p2159698.html

on to them
 
looks like i'm gonna have to give up on the carver, they just replied saying they wouldn't recommend shortening it to 68 due to chainline issues, and i understand why , i think i may have to stick with the ritchey, or a hardtail.
GnarvesterFrameWhite-Detail-7.jpg
 
Anyone make progress on fitting a TDCM torque sensor to a 73mm bottom bracket? I'm trying to build a new bike and most of the frames I'm looking at all seem to have 73mm bottom brackets.
 
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