GRX 2x on Genesis V...
 

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[Closed] GRX 2x on Genesis Vagabond 2021??

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Good evening,

I'm thinking about buying the frame but am unsure if it can take the GRX-RX600 crank set with 46/30 teeth. Anyone here who has the newest version and could tell me more about it?

The information on their website is not accurate unfortunately and they havent replied to my emails so far.

Cheers


 
Posted : 11/03/2021 8:16 pm
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I have the new frame and I've just built it up.
I was planning to do the same thing, but then had a good look at the gearing with the larger tyres and decided to fit an SLX chainset instead.
Mine is geared 38/28 at the front, 11-34 at the rear, with scope to go to 11-36 easily.

I lose a few inches in top end gearing, but keep a good spread of gears with less jumps between the gears than I would with a 46/30 double.

Shifters are 105, with an SLX front mech and 105 rear.

The bottom bracket shell is 68mm, so you could almost certainly fit a GRX chainset, as the info sheet claims that a 46t chainring will fit. I've seen someone who failed to fit a 105 chainset, but I suspect that the chainline is tighter and of course the chainring is larger.

I literally only finished the bike at the weekend, so it's had just one 10km shakedown ride, so it needs a few tweaks, but it felt pretty good "out of the box".


 
Posted : 16/03/2021 11:02 am
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The information on their website is not accurate unfortunately and they havent replied to my emails so far.

So did I. No reply. Rubbish isn't it.


 
Posted : 16/03/2021 11:05 am
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thanks for your reply.

someone on reddit has also bought the bike just recently and tried to fit a grx 46/30 crankset. here is the picture. pretty tight. im not sure if thats smart...


 
Posted : 16/03/2021 10:29 pm
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@jojojojo, I’d space the bb out and use that, it’s exactly what i did with my surly.

No help to the op of course.


 
Posted : 16/03/2021 10:36 pm
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ok. that sounds like a good idea 🙂 thanks.

ps. im the op as well 😀


 
Posted : 16/03/2021 10:38 pm
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Just realised jojojo is the op.
Been a long day.
If the one on reddit was mine id put one spacer over to the drive side, i think that’s 2.5mm, which would make me feel a lot better.
I don’t know if that helps you or not. You could ask the poster on reddit for a pic of the near side of the bb to see how much room there is to play with, then make an assessment.


 
Posted : 16/03/2021 10:41 pm
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😂😂


 
Posted : 16/03/2021 10:41 pm
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yeah 2.5 mm on each side. a 156mm q-factor of the grx crank (with the 73mm bb) would still be in acceptable range for my knees. thanks for helping out!


 
Posted : 16/03/2021 11:14 pm
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If you put a 2.5mm spacer on each side there won't be enough axle engagement with the LH crank.


 
Posted : 17/03/2021 7:19 am
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but isnt it a bad idea to mount the crank arms asymmetric? i mean the 2.5mm offset on only the drive side.


 
Posted : 17/03/2021 9:22 am
 PJay
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The bottom bracket shell is 68mm, so you could almost certainly fit a GRX chainset

The chainline for the GRX is only 46.9 though, so it'll be closer to the stays (I think that a MTB double chainline is 48.8).

The Vagabond frameset page doesn't list the BB width, but for the [url= https://www.genesisbikes.co.uk/genesis-vagabond-vargn21500 ]full bike[/url] it lists the fitted BB as a SRAM GXP XR 73mm and I wasn't sure whether the 73mm refers to the shell width.


 
Posted : 17/03/2021 9:50 am
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but isnt it a bad idea to mount the crank arms asymmetric? i mean the 2.5mm offset on only the drive side.

It's a worse idea not to engage the splines fully. Even a single 2.5mm spacer is not advisable. The cranks are not designed to be used with bb spacers.


 
Posted : 17/03/2021 9:55 am
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It’s a worse idea not to engage the splines fully. Even a single 2.5mm spacer is not advisable. The cranks are not designed to be used with bb spacers.

thanks for bringing up the point.

The Vagabond frameset page doesn’t list the BB width

i had some folks measure the width on their 2021 frames and they confirmed its 68mm .


 
Posted : 17/03/2021 10:09 am

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