What crankset for my bike with BB86

russboy

Hi all,

Need some advise really as want to replace my crankset as it's showing signs of wear now.

Previously replaced my chain & cassette so this is next in line after a few thousand miles in the last 2 years. Plus the left arm has worked a little loose and as I didn't notice it's rounded of a little now.

So what's a straight fit as ideally I don't want to replace the BB? I would like at least the same spec poss higher but don't want to spend fortunes.

So what do you reckon to go for?

This is the original spec of the bike:



The current crankset:



Thanks all,

Russ

DKay

A few thousand miles on a set of chainrings is nothing, assuming that you've replaced the chain and cassette regularly (as you have), kept up with maintenance and don't crosschain like a bugger. This is expecially true for Praxis Works chainrings, which are some of the most durable on the market.

Personally, I'd junk your current cranks as they're knackered, sell the chainrings and then just buy a 5800 chainset for £70, as it will cosmetically match the rest of your groupset and work perfectly well.

timothyw

Unfortunately the existing bottom bracket you have will be a 'GXP' type, so a shimano 5800 chainset will not be compatible, you'd need to replace the bottom bracket also.

This would be a straight replacement:
http://www.chainreactioncycles.com/sram-apex-white-gxp-compact-10sp-chainset/rp-prod83674

Personally I'd stick with your existing chainset until it/the bottom bracket fails, then replace them for a shimano chainset and BB combination so as to match the rest of the groupset.

russboy

Thanks all.

I could consider replacing the BB as well I suppose as I guess that would open up to a whole load of options.

I’d just be worried as the BB is a pushfit & I haven’t got the tools to remove it & I don’t really want to be smashing 7 bells out of it with a hammer. I changed the BB & crankset on my MTB but that wasn’t too bad to remove as that screwed in & the tool was cheap.

keef66

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739412#p19739412]Russboy[/url] wrote:

Thanks all.

I could consider replacing the BB as well I suppose as I guess that would open up to a whole load of options.

I’d just be worried as the BB is a pushfit & I haven’t got the tools to remove it & I don’t really want to be smashing 7 bells out of it with a hammer. I changed the BB & crankset on my MTB but that wasn’t too bad to remove as that screwed in & the tool was cheap.

Then take the cranks off and get a bike shop to replace the BB for you?

russboy

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739442#p19739442]keef66[/url] wrote:

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739412#p19739412]Russboy[/url] wrote:

Thanks all.

I could consider replacing the BB as well I suppose as I guess that would open up to a whole load of options.

I’d just be worried as the BB is a pushfit & I haven’t got the tools to remove it & I don’t really want to be smashing 7 bells out of it with a hammer. I changed the BB & crankset on my MTB but that wasn’t too bad to remove as that screwed in & the tool was cheap.

Then take the cranks off and get a bike shop to replace the BB for you?

True, but I don't like paying someone else for the work I can do myself

Guess the tool might only be a little more that a bike shop would charge to remove it, will have a nose around & see what I can get it for. Edit to say - Can be bought for £40.

So on the presumption I do change the BB what are my options then for a crankset, or is it endless?

keef66

You can probably tap out the existing BB easily enough using things you already have in your toolbox, and press in the new one using a bit of threaded rod, some nuts and large washers. Enterprising individuals are selling them as 'headset presses' on Ebay for around a fiver. I bought one to press in the headset cups on my CR1; it's fine as long as you ensure the things are going in straight.

The world's your lobster as far as new crankset / BB options go. Just make sure whatever crankset you buy includes a BB86 press-fit BB. Bang per buck the 5800 crankset is hard to beat...

russboy

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739558#p19739558]keef66[/url] wrote:

You can probably tap out the existing BB easily enough using things you already have in your toolbox, and press in the new one using a bit of threaded rod, some nuts and large washers. Enterprising individuals are selling them as 'headset presses' on Ebay for around a fiver. I bought one to press in the headset cups on my CR1; it's fine as long as you ensure the things are going in straight.

The world's your lobster as far as new crankset / BB options go. Just make sure whatever crankset you buy includes a BB86 press-fit BB. Bang per buck the 5800 crankset is hard to beat...

Cool, thanks.

Where you say I have to have a pushfit BB, I presume this crankset wouldn't be any good:

http://www.wiggle.co.uk/shimano-105-5750-hollowtech-ii-compact-chainset/?lang=en&curr=GBP&dest=1&sku=5360416669&ci_src=18615224&ci_sku=5360416669uk&utm_source=google&utm_term&utm_campaign=UK_PLA_Components&utm_medium=base&utm_content=sIcpiV8SB_dc%7cpcrid%7c67090789262%7cpkw%7c%7cpmt%7c%7cprd%7c5360416669uk

Because it uses a threaded BB such as here:

http://www.wiggle.co.uk/shimano-bb-r60-ultegra-6800105-5800-hollowtech-ii/

So essentially are you saying I'm not able to use any threaded BB as there will be no thread on my frame as it would only use pushfit BB's?

dwanes

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739594#p19739594]Russboy[/url] wrote:

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739558#p19739558]keef66[/url] wrote:

You can probably tap out the existing BB easily enough using things you already have in your toolbox, and press in the new one using a bit of threaded rod, some nuts and large washers. Enterprising individuals are selling them as 'headset presses' on Ebay for around a fiver. I bought one to press in the headset cups on my CR1; it's fine as long as you ensure the things are going in straight.

The world's your lobster as far as new crankset / BB options go. Just make sure whatever crankset you buy includes a BB86 press-fit BB. Bang per buck the 5800 crankset is hard to beat...

Cool, thanks.

Where you say I have to have a pushfit BB, I presume this crankset wouldn't be any good:

http://www.wiggle.co.uk/shimano-105-5750-hollowtech-ii-compact-chainset/?lang=en&curr=GBP&dest=1&sku=5360416669&ci_src=18615224&ci_sku=5360416669uk&utm_source=google&utm_term&utm_campaign=UK_PLA_Components&utm_medium=base&utm_content=sIcpiV8SB_dc%7cpcrid%7c67090789262%7cpkw%7c%7cpmt%7c%7cprd%7c5360416669uk

Because it uses a threaded BB such as here:

http://www.wiggle.co.uk/shimano-bb-r60-ultegra-6800105-5800-hollowtech-ii/

So essentially are you saying I'm not able to use any threaded BB as there will be no thread on my frame as it would only use pushfit BB's?

The crankset you highlighted will be fine, and should be the one to go for to match the rest of your groupset.

The BB needs to be a (Shimano) Pressfit BB suitable for BB86

Then you are good to go.

dwanes

This one i guess, unless any one cares to disagree?
http://www.chainreactioncycles.com/shimano-bb71-road-press-fit-bottom-bracket/rp-prod61803

russboy

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739610#p19739610]dwanes[/url] wrote:

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739594#p19739594]Russboy[/url] wrote:

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739558#p19739558]keef66[/url] wrote:

You can probably tap out the existing BB easily enough using things you already have in your toolbox, and press in the new one using a bit of threaded rod, some nuts and large washers. Enterprising individuals are selling them as 'headset presses' on Ebay for around a fiver. I bought one to press in the headset cups on my CR1; it's fine as long as you ensure the things are going in straight.

The world's your lobster as far as new crankset / BB options go. Just make sure whatever crankset you buy includes a BB86 press-fit BB. Bang per buck the 5800 crankset is hard to beat...

Cool, thanks.

Where you say I have to have a pushfit BB, I presume this crankset wouldn't be any good:

http://www.wiggle.co.uk/shimano-105-5750-hollowtech-ii-compact-chainset/?lang=en&curr=GBP&dest=1&sku=5360416669&ci_src=18615224&ci_sku=5360416669uk&utm_source=google&utm_term&utm_campaign=UK_PLA_Components&utm_medium=base&utm_content=sIcpiV8SB_dc%7cpcrid%7c67090789262%7cpkw%7c%7cpmt%7c%7cprd%7c5360416669uk

Because it uses a threaded BB such as here:

http://www.wiggle.co.uk/shimano-bb-r60-ultegra-6800105-5800-hollowtech-ii/

So essentially are you saying I'm not able to use any threaded BB as there will be no thread on my frame as it would only use pushfit BB's?

The crankset you highlighted will be fine, and should be the one to go for to match the rest of your groupset.

The BB needs to be a (Shimano) Pressfit BB suitable for BB86

Then you are good to go.

Thanks, I see there are various lengths to go for such as 165mm, 170mm, 172.5mm & 175mm, so is there any particular to go for? Or I guess a better question is what are the parameters that help you decide which one to go for?

keef66

Those measurements refer to the length of the cranks. Usually longer legs = longer cranks, but it's a matter of personal preference. Manufacturers often fit shorter cranks on the smaller sizes /172.5 on the mid range / longer ones on the XL.

At 5'6" I'm a bit of a shortarse; I have 165mm cranks on the winter bike and 170 on the summer one. The shorter cranks feel more spinny, which suits me when I'm struggling into a Westerly gale.

dwanes

What size is your frame Russboy?

russboy

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739700#p19739700]dwanes[/url] wrote:

What size is your frame Russboy?

59cm if memory serves me well & i'm 6' 1" tall.

russboy

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739614#p19739614]dwanes[/url] wrote:

This one i guess, unless any one cares to disagree?
http://www.chainreactioncycles.com/shimano-bb71-road-press-fit-bottom-bracket/rp-prod61803

Anyone agree/disagree as having ridden the bike home it's now horrendous so I need to get ordering some new parts!

So to summaries its a size 59cm frame, I'm 6' 1" and I'm pretty much set on this crankset:

http://www.wiggle.co.uk/shimano-105-5750-hollowtech-ii-compact-chainset/?lang=en&curr=GBP&dest=1&sku=5360416669&ci_src=18615224&ci_sku=5360416669uk&utm_source=google&utm_term&utm_campaign=UK_PLA_Components&utm_medium=base&utm_content=sIcpiV8SB_dc%7cpcrid%7c67090789262%7cpkw%7c%7cpmt%7c%7cprd%7c5360416669uk

So if I order that crankset what length would people go for & which BB?

Thanks again all, much appreciated.

Russ

me-109

That BB will be fine for that chainset. Length is personal as much as anything and doesn't have to be related to height - depends on what research/history you want to believe. 170 used to be standard. Theory is that shorter is more spinny, longer is slower but gives more leverage. Current philosophy would probably put you on 172.5 but you could go up or down a size and not notice.

dwanes

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739951#p19739951]Russboy[/url] wrote:

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19739614#p19739614]dwanes[/url] wrote:

This one i guess, unless any one cares to disagree?
http://www.chainreactioncycles.com/shimano-bb71-road-press-fit-bottom-bracket/rp-prod61803

Anyone agree/disagree as having ridden the bike home it's now horrendous so I need to get ordering some new parts!

So to summaries its a size 59cm frame, I'm 6' 1" and I'm pretty much set on this crankset:

http://www.wiggle.co.uk/shimano-105-5750-hollowtech-ii-compact-chainset/?lang=en&curr=GBP&dest=1&sku=5360416669&ci_src=18615224&ci_sku=5360416669uk&utm_source=google&utm_term&utm_campaign=UK_PLA_Components&utm_medium=base&utm_content=sIcpiV8SB_dc%7cpcrid%7c67090789262%7cpkw%7c%7cpmt%7c%7cprd%7c5360416669uk

So if I order that crankset what length would people go for & which BB?

Thanks again all, much appreciated.

Russ

Chances are that your current one will be 172.5 so i would go with that, no shorter given your height.

russboy

So this:

http://www.chainreactioncycles.com/shimano-bb71-road-press-fit-bottom-bracket/rp-prod61803?utm_source=awin&utm_medium=link&utm_campaign=generic78888&awc=2698_1447677094_a6f4d50990b07e160ef9621645eb25c9

and this:

http://www.chainreactioncycles.com/shimano-105-5750-compact-10sp-chainset/rp-prod50444

were delivered on Saturday morning, just in time really!

Local bike shop wanted £30 to take out the old BB & fit the new one, except from when talking to them they said "yes they do make a special tool for doing this", however they didn't confirm they had one so I thought if your just going to use a hammer I might as well do it myself & save £30!

Weather was awful all day so started working on it yesterday. Removing the crankset was easy as have had to do it a dozen times already. To remove the pushfit BB I'd already given it some thought & had spotted a spare seatpost in my shed with the saddle mount having a rectangular nut. So stripped that off, pushed it inside the frame & then turned it over so that it rested on the inside edge of the BB but on opposite sides so as to spread the load. Then dropped a bolt into the frame from above, screwed it into the rectangular nut & then got the hammer out. Rotated it a few times again to spread the load & within a few mins one side was out. Spun the bike over & dropped a large socket into the hole & the other side came out with 2 taps from a hammer.

To fit the new BB I put it into place & put a large threaded rod through the middle of it all, 1 large washer either side & a wing nut on the outside of each washer & slowly tightened it up. In the end I was able to do it by hand so no over tightening. Although when one side finally met the other & popped into place the noise wasn't great, but all looks to be fine.

Had a very quick ride down the farm road last night & then used it for my commute in today & all is well!!

So thanks everyone for your input, much appreciated. Oh & I went for a 175mm length in the end, which was just as well as that's the same as the one I took off!

dwanes

Well done, it is very satisfying doing things yourself, saving money and learning.
It will be a doddle to do next time.