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I have a Kona Big Honzo. Use it a lot. Bottom bracket/cranset is Truvativ and is made of cheese. I'm on my third bottom bracket this year. At £35 each this is getting silly.
I would like to replace this with something a bit(a lot) more robust. Presumably this means new bb and crankset. Way out of my depth on the techy side of things so have no idea what is suitable. The only thing I can think about is chainline or does this not vary with different makes?
I would think of external bb cups so does that mean Shimano? If so which one? Are there other alternatives? I don't mind spending a bit but am not into the silly money for bling market.
Can your collective wisdom guide me?
Shimano SLX chainset paired with a Hope BB would be my fit and forget choice. Merlin have good prices on Shimano chain sets at the moment. Current Shimano 1x are mostly 52mm chainline.
Chain line of 52mm works on non boost and boost. 8100 for Shimano XT
55mm for boost 8120 for XT
I assume 56.5mm is fit super boost. 8130
What length cranks do you want?
I've got 8100 XT 175s I took off my Occam I could sell.
I'm also about to take the 8120s (170mm) off my new Slash.
Shout if you wanna buy either of them
SLX chainset and Shimano BB would be my choice.
You could grab a couple of these with your crankset from Merlin.
Thanks guys. You say 52mm chainline. How do I measure this? Is it from the edge of the shell to the teeth? Or something else.
Excuse my ignorance - I'm a reconstituted roadie!!!
Just been into garage with tape measure. FRom middle of bb shell to teeth looks to be 52mm Is this right?
Cranks are SRAM SX and from the poor stamping seem to be 175.
Sorry, don't know what boost is - guess I haven't got it.
Shimano definitely for the 24mm axle durability. Deore and slx are all fine, but thegeneralist's xts would be ideal too.
52mm chainline for shimano is boost. 50mm or a bit less would be non-boost.
I have a Kona Big Honzo. Use it a lot. Bottom bracket/cranset is Truvativ and is made of cheese. I'm on my third bottom bracket this year. At £35 each this is getting silly.
3 BB's in one of the driest 6-month spells we've had in years - sounds like you're not installing them right and/or incorrect spacers etc.
Chain line of 52mm works on non boost and boost. 8100 for Shimano XT
55mm for boost 8120 for XT
I assume 56.5mm is fit super boost. 8130
What length cranks do you want?
I've got 8100 XT 175s I took off my Occam I could sell.
I'm also about to take the 8120s (170mm) off my new Slash.
Shout if you wanna buy either of them
Thanks. Cranks are 175. Chainring is 30T. What teeth are yours?
I've been riding in sand, wet sand for 6 months. Ruins everything.I have a Kona Big Honzo. Use it a lot. Bottom bracket/cranset is Truvativ and is made of cheese. I'm on my third bottom bracket this year. At £35 each this is getting silly.
3 BB's in one of the driest 6-month spells we've had in years - sounds like you're not installing them right and/or incorrect spacers etc.
Shimano definitely for the 24mm axle durability. Deore and slx are all fine, but thegeneralist's xts would be ideal too.
52mm chainline for shimano is boost. 50mm or a bit less would be non-boost.
Thanks. Can you tell me how to measure this accurately? I'm floundering a bit.
Take everything below with a pinch of salt because I am not 100% sure...
Afaik, you just need to know if your wheels are boost or not. I * think* boost is 148mm rear width,
And looking at the 2022 model on Kona .com
Rear Hub Shimano 148x12mm (centerlock)
Ie the hub is boost
So the frame/ chain set is too...
Afaik, you just need to know if your wheels are boost or not. I * think* boost is 148mm rear width,
Just checked. Rear wheel is 148. So what is boost?
Boost is the wider axle than the older standard of 135mm quick release axle. Boost is the pretty much what all modern bikes are so is now the norm.
I've got a Shimano Deore crankset in the classifieds for £15 posted, bit worn as been well used but will last for a good few years yet. 170mm length with 30 tooth chainring.
Then buy an XT bottom bracket for about £15 or something!
Yes, you have already measured the chainline correctly at 52mm, and the rear hub is 148mm so it's all boost standard. So one of thegeneralist's or a new shimano crank that has a 52mm chainline is fine. Don't get anything with a chainline of 56.5mm (eg a M8130 crankset) as that's for a 157mm rear hub (superboost).
You can also use a 55mm chainline crankset if you want as shimano say that is also boost. It's only about one rear cog spacing difference anyway, but as you already have a 52mm chainline, I would stick with that as it will run better in the lower gears where it's most noticeable.
If you think you need more chainring to chainstay clearance, or want to run a massive chainring, then you might want to use a 55mm chainline crankset. Shimano say 52 and 55 are fine for boost.
If it was me, I would stick to a 52mm chainline crankset where possible as it's a better low gear chainline and reduces the chances of chaindrop when backpedalling in low gears.
Yak, since you seem to be very knowledgeable about this...
When I got my Slash the other day the mechanic tried to fit my 165mm 8100 52mm crankset to it but said the crank axle was too short and I need a longer one.
M-8120 is of course the 55mm chain line as mentioned above, but does it also have a longer axle?
Aren't they the same, apart from the axle being longer?
If it's a standard BB shell width eg 73mm then do you have an extra (non) bb spacer?
Thanks guys - again.
I'm just a reconstituted roadie who got fed up of being knocked off and seeing plod look the other way.
Fortunately we have some good pinewoods stuff round here with nice singletrack sections - lots of fat bikes also - so I dived in there. I've got a lot to learn.
A lot to think about there.
I agree with earlier recommendations. SLX 170mm in 30t from Merlin with that £8.50 BB. Been running that for a while.
You'll need the pre load tool. Hand tight and then back off a quarter of a turn gives you extremely long durability.
You'll need the tool for the BB too, very useful to have. 1 spacer on the drive side if your BB shell is 73mm (probably is).
This combo genuinely is fit and forget for very little money.
I assume you run a Shimano chain but if you run a SRAM chain you'll need a works components ring. But you'll get £25 back or so when you sell the new SLX ring. Although you'll also need the tool to swap the rings lol.
+1 slx crankset
nothing comes close on price vs weight vs durability imo
I've been riding in sand, wet sand for 6 months. Ruins everything.
I ride in a lot of sand and have the same experience. Hope bottom bracket bearings are particularly prone to wear so I don't use them any more.
Shimano ht2 external bearing bottom brackets are ideal for price vs durability. Personally I don’t love 12 speed Shimano chains or chainrings - they skip about more in bad weather than SRAM ones. Also the 12 speed chainrings have a daft 2 piece design with no replaceable security bolts that fail over time.
If you’re on a sram chain now I’d look to pick up either slx or xt cranks with no chainring and then pickup any other 12 speed Shimano/ eagle compatible chainring that’ll fit on a Shimano crank. They have a locking with a proprietary tool to fit which is annoying but the tool isn’t expensive.
From your description you have a very heavy SRAM SX crankset with the cheap and crap cartridge bottom bracket with inboard bearings. If you wanted to stay SRAM you could go for a GX or higher Dub bottom bracket standard. They don’t last as long as hollowtech but they’re ok - and the SRAM chainrings are very decent, don’t cost the earth and have a 3 Torx bolt fitting method that doesn’t need proprietary tools to change the chainring.
Looking about this SLX crankset is hard to beat for price
Bottom Bracket from the same shop
If you’d prefer SRAM then these aren’t badly priced and the steel chainring will last forever.
Bb to fit:
“Also the 12 speed chainrings have a daft 2 piece design with no replaceable security bolts that fail over time. ”
I just noticed that one of the (eight?) bolts is undoing on my SLX M7200 chainset - are they standard security Torx (with the pin in the middle so you can’t use a normal Torx)?
I’ve only used it with a SRAM chain as a singlespeed, which seems to work fine!
It’s hard to get 24mm axle 165mm cranks at a decent price.
@sea level
The SLX cranks that Bristol linked to are indeed a bargain.
If you would rather have XT written on the side of them then I've put mine in the classifieds and will match that price. The 55mm ones are almost brand new, the 52mm ones were used a few more times. Can do either 30 or 32T.
https://singletrackworld.com/advert/2-shimano-deore-xt-cranksets-170-175mm-30t-32t-chainring/