Sram Force GXP BB Play

[foreigngreg]

@alcatraz: It is a GXP BB, got the star-like dust cover on the nds. I am pretty confident by now that everything was set up right...

@Hambini: Right, I think in some cases the bearing itself has play (this is what happens to me as the tolerances are quite tight on the axle in my case (tight enough for play there to not be felt).

I now mounted an FSA spring-wave-washer on the ds, this has solved the play issue, they spin very freely (just as before) except without any noticable play. I think in this setup it is a very good system as it is not possible to exessively preload the bearings this way.

[kyleFu]

the other thing could also be that the washer.

HI John, thanks for your private messages and sorry for late reply as I just saw it, with the failure to reply directly on "private messages" page and have no access to your email, so I have a try to write you here, for more convenient contact may you write me email
? All the best.

[Kurt1980]

Your post has highlighted one of the reasons why I elected to stop making GXP bottom brackets. The length of the axle and specifically the 24mm can vary by quite a bit. If you have a slightly tight female taper and large male taper which is quite possible, you'll get play on the axle. As others have said the drive side is free floating.

I did a case study on youtube about GXP on a trek madone where I removed the need to make the non drive side fixed and also one of the czech cycling teams I supply ditched the fixed non drive side. They have them set up to behave more like Shimano units.

Hambini

I know this chap is long gone from WW, but I had a question about the above.

Can anyone tell me what he meant by removing the need to make the NDS fixed? Did he somehow make the spindle a straight 24mm? Or machine away the spindle step on the NDS and use a wave washers on each side?

I'm scratching my head trying to figure this out.

Context- my first gen Scott Foil runs GXP. The internal cable guide at the BB looks like it prevents the use of a BB infinite module. Looking for other upgrade possibilities.
Kurt

[Aeo]

You can use something like this adapter https://www.bike-components.de/en/Acros ... ts-p43577/ (the top left aluminium ring) to convert the 22mm side of the spindle back to 24mm

The other option is using a Delrin spacer by Hambini to fit inside a 6805 bearing to receive the 22mm side

Then you can use spacers instead of the wave washer to set the crank up without play

[TobinHatesYou]

I know this chap is long gone from WW, but I had a question about the above.

Can anyone tell me what he meant by removing the need to make the NDS fixed? Did he somehow make the spindle a straight 24mm?

In short, yes. A 1mm sleeve is placed over the 22mm diameter portion of the spindle. Some combination of spacers + one wave washer on the DS will take up any play.

[Kurt1980]

I know this chap is long gone from WW, but I had a question about the above.

Can anyone tell me what he meant by removing the need to make the NDS fixed? Did he somehow make the spindle a straight 24mm?

In short, yes. A 1mm sleeve is placed over the 22mm diameter portion of the spindle. Some combination of spacers + one wave washer on the DS will take up any play.

Yeah ok, so floating on both sides?

Have you or anyone else ever run GXP this way? Any noticeable difference?

[Kurt1980]

You can use something like this adapter https://www.bike-components.de/en/Acros ... ts-p43577/ (the top left aluminium ring) to convert the 22mm side of the spindle back to 24mm

The other option is using a Delrin spacer by Hambini to fit inside a 6805 bearing to receive the 22mm side

Then you can use spacers instead of the wave washer to set the crank up without play

Any advantage to using spacers instead of wave washers?

[TobinHatesYou]

Have you or anyone else ever run GXP this way? Any noticeable difference?

Chris King bottom brackets are adapted to GXP this way. I didn’t notice any difference.

I wouldn’t call it “floating in both sides” since that somehow implies each side floats independently of each other. Obviously they are a single rigid structure and only one wave washer is required.

[rcrowley]

My SRAM Red GXP crankset (eTap-era) has this kind of play.

It's not like the spindle's too long. I verified by experimenting with several combinations of spacers from 0.1mm to 1mm. They either did nothing, made the pedals hard to turn, or made it impossible to torque.

It is, as several have noted, as if the spindle's too narrow. I solved it by adding a wrap or two of Teflon plumber's tape between the spindle and the shim that's supposed to be between the spindle and the bearing on both sides.