Sram Red cranks and BB30A Bottombracket.

[TLN]

Hi all.

Trying to swap crankset with spider to integrated one. Both are BB30/PF30.
Old crankset set up with gray lockring spacer on NDR, big (10-12mm) spacer on DR side.
Integrated crankest comes with lockring spacer on NDR side, with no spacer on DR side and is also shorter.
At first, I was a bit scared: axle is way longer then existing one. After reading forums I figured out that it's not too bad:
In order to install crankset with integrated spider I'll need to remove grey lockring from NDR side, and replace it with wavy washer and some shims. And after all it will be same q-factor and everything as with my existing set up.
Does this sounds like a plan?
I guess I need to get this kit: https://www.amazon.com/gp/product/B0050 ... 1DF1&psc=1
I might have wave washer somewhere btw.

Thanks.

[alcatraz]

Sure the old crank isn't bb386? Sounds like it could be.

The current bb might not support bb30 if it's designed for bb386 (long spindles). If the cups/bearings are internal with no portrusions outside the frame I think it should work with the existing bb.

In any case a sram red crank (w. int. spider) should work with a bb/pf30a frame so feel free to buy it.

[Beaver]

If it's about this bike, your old crank had a bb386 axle and the replacement will work as planned. You will also increase bearing life by doing so.

[TLN]

Sure the old crank isn't bb386? Sounds like it could be.

The current bb might not support bb30 if it's designed for bb386 (long spindles). If the cups/bearings are internal with no portrusions outside the frame I think it should work with the existing bb.

In any case a sram red crank (w. int. spider) should work with a bb/pf30a frame so feel free to buy it.

Yeah, it sounds like my old crank is BB386. I thought newer Sram RED cranks come in only on BB30 and GXP versions.

I've just installed crankset with integrated spider without lockring. Worked great. Still need to get wavy washer and spacers, but it will be delivered in a few days.

If it's about this bike, your old crank had a bb386 axle and the replacement will work as planned. You will also increase bearing life by doing so.

Speakign of bearings, why's that? Because we eliminate lever by using shorter spindle?

PS. Weight savings:
1. Spindle comparsions:

2. BB386 crank vs BB30 crank
249gm vs 178gm

3. Chainrings.
Metal spider, 53/39, 172.5mm length vs integrated spider, 52/38, 175mm length
440gm vs 358gm. Actually former crank required spacer on drive side.

4. Complete weight, former crank without spacer that adds 8-10gm:
538 vs 694gm.

So it's almost 160gm lighter, looks better and will increase bearing life. Sounds like a win to me

[Beaver]

Speakign of bearings, why's that? Because we eliminate lever by using shorter spindle?

Yes, angular contact bearings may help here but they also have a little more drag. A matching frame/crank combo is just the best.

And you may shave another 20g later, when you switch to Praxis Works chainrings (shifting quality and durability are equal).

[TLN]

Speakign of bearings, why's that? Because we eliminate lever by using shorter spindle?

Yes, angular contact bearings may help here but they also have a little more drag. A matching frame/crank combo is just the best.

And you may shave another 20g later, when you switch to Praxis Works chainrings (shifting quality and durability are equal).

I don't think I'll bother about 20gm honestly.

Now the biggest question, is what was my previuous crankset? BB386? I got 5mm lockring on NDS, BB73 bracket in Synapse 2018 and 13 or 15mm spacer on drive side.

[Beaver]

Should be BB386: https://r2-bike.com/SRAM-RED-eTap-Crank ... th-1725-mm