Any question answered...

Cyclocross people were gluing 33mm tubs to narrow road rims for yonks so you should be ok with anything.

Maybe ask the guys in the tub thread

I was thinking the same but needed reassurance.

Thanks and good idea about the tub thread!

Any suggestions for digital calipers, preferably reasonably cheap? Need to measure a seattube but can't get the bike to a shop. I would usually just buy the most popular thing on Amazon but that doesn't always work out very well.

Cheap one seemed to work fine, moreso you can use it like a normal one without relying on the digital scale.

I would usually just buy the most popular thing on Amazon

Do this, there's no evidence that there's anything to choose between any of the cheap Chinese ones. If you want to invest in a really nice tool to last a life time which has as much accuracy and precision as you need for bike related work, you could spend £35 on a Mitutoyo 530-101 Vernier caliper, but that's very much #tartmode and a £10 Chinese digital one will be more convenient and will still most likely work fine for many years.

And take the batteries out after every use because the slightest movement will turn the cheap chinese ones back on. Or just stock up on LR44 batteries.

stock up on LR44 batteries

The popular (Tacklife) one on Amazon takes CR2032, which is probably reason enough to pick it over the LR44 powered ones, just because you can always get CR2032s at the corner shop when you need one in an emergency.

My digi caliper came from Lidl, reduced to clear. It doesn't turn itself on when measuring. Not sure what its equivalent Chinese model number is but it's worked well for over a year now.

How accurate is the power estimate on Strava?

@pdlouche I'm in Lidl like 3 times a week as it's about a 2 minute walk from my flat. Unfortunately they've not had any in recently or I'd have bought one already. Bet they have them in 2 weeks or something.

@mdcc_tester @Aroogah @edscoble thanks guys. That one on Amazon looks fine, think I'll go for that. Cheers. In a few years when I have a real job (currently on PhD wages) I'll maybe donate these cheap tools to someone and buy nice stuff instead.

About as accurate as any other Fermi Estimation

I think I got mine around Aug/Sept on clearance so probably you missed them. It's incredibly hit and miss but still better odds than Euromillions.

Hey guys,

I'm really struggling to find a set of cranks that can fit on my frame and and clear the rear chain stays.

I've got a set of sram force 1 cranks that might work with a small chainring 38t. ( does anyone have one?) however I need a bb to really check. Can anyone tell me a way of check before ordering a bb or do I just have to try? Is the SRAM GXP 68mm bb suitable to use getting confused with the mentioning of BB30.

Secondly if this doesn't work I might try Deore XT. Again is it just buy and try?

Finally I think the white industries G30 might help in this predicament but how can I be sure before ordering them? ( where can I get them from!)

Whats the frame? Your cranks are GXP or BB30?
Bottom bracket will make no difference because the crank has a set axle width already

Custom frame.

Okay so bb shell is 68mm.

Cranks are SRAM force 1 just getting really confused..

MTB Cranks = wider Q factor.

If its custom get the stays crimped.

Sram have both GXP and BB30 versions of many of their cranks.

GXP cranks have an axle which is 24mm diameter, but tapers to 22mm at one end.

BB30 cranks have a 30mm axle.

Haha, you should see what I've done...

Pics of crank axle pls

Inverse crimp?

Basically, you can't change how wide your crank is or how far out it sits. Your frame clearance is your frame clearance. You will need to know whether your cranks are standard GXP or BB30, it will quite simply say BB30 or PF30 on the axle and if not, its probably gxp. Measure if you're not sure, 24mm axle vs 30mm. Get the BB that corresponds. Since you don't have a bb30 frame, you'll need an adapter bb to use bb30 cranks in a bsa frame

You could maybe do something funky with removing the preload ring on bb30 cranks and spacing it on the drive side, I don't know.

https://sram-cdn-pull-zone-gsdesign.netdna-ssl.com/cdn/farfuture/Xf-_GsO_0nsYPvZBCugVIAvgearLIBOgEqK-uU7KQok/mtime:1501777201/sites/default/files/techdocs/95-6118-015-000_rev_c_road_cranksets_and_bottom_brackets_0.pdf

According to this It looks like i can use bb30 or the normal GXP bb..

Pretty accurate for climbs without much wind to account for. PowerTap hub and strava agreed to within about 10w for a run up Mott St. You'll need to be accurate with your bike and rider weight though.

Totally unreliable on the flat or with wind to account for.

They're different sizes. One or the other, not either

?

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