Pedel bike Cranks

[Toyotanut]

Looks like I need a crank. Any one brand better than another. It's for a mountain bike. 8 gears in the back 3 up front. I'm also on a $$$ budget. Have no idea what I should be looking for when looking at them. Any help would be appreciated.

 

[Boonie Buster]

Is it the bottom bracket or crank arms you needs? Im assuming its the bearing portion that goes into the frame and not the crank arms themselves. First you gotta figure out what style you have, look on park tools website or Scott browns website for bottom bracket info.
But I got a FSA (Full Speed Ahead) bottom bracket recently that seems to run fairly smooth. $60 or so.

If you are wanting to do it yourself I have some of the special tools to remove those parts, hopefully they're the same!

 

[Glenn]

I have never had a problem with the crank itself. What is the specific issue you're having?

 

[Toyotanut]

I need to replace mine due to the spacing for the gears are incorrect. Found that out when I took the bike in to get it adjusted. I'm getting "chainsuck"(chain gets stuck between the gears) when trying to shift. I guess the crank is for a 6 speed instead of an 8 speed(rear gear set). Hope that makes sense to you all.

 

[Glenn]

Is this thw way it was sold to you? Take it back and make them fix it. The guy who assembled that bike screwed up.

 

[Boonie Buster]

That doesn't make sense to me. How many gears are on the rear cassette? My theory from what you've said: the chain is getting stuck because you have too few of gears on the rear cassette. Or the chain is too narrow for the setup.

 

[Toyotanut]

That doesn't make sense to me. How many gears are on the rear cassette? My theory from what you've said: the chain is getting stuck because you have too few of gears on the rear cassette. Or the chain is too narrow for the setup.

I've got 8 gears on the rear cassette.

Is this thw way it was sold to you? Take it back and make them fix it. The guy who assembled that bike screwed up.

Was bought at Raliegh/Diamondback Friends and Family Sale. Was a "Demo/Show" bike.

 

[Boonie Buster]

Maybe it needs a 9spd rear cassette? I think I still have a shimano one in my parts box...*checks box o' parts*... yup, I have a 9spd cassette. Is that what the shop sa:corn:id you need? :eeek:

I wanna say I had this issue when I switched wheelsets....you would go to shift gears and the chain would bind in the rear cassette between two gears...

I still stand by you needing a wider chain or 9spd cassette.:corn:

 

[Toyotanut]

Maybe it needs a 9spd rear cassette? I think I still have a shimano one in my parts box...*checks box o' parts*... yup, I have a 9spd cassette. Is that what the shop sa:corn:id you need? :eeek:

I wanna say I had this issue when I switched wheelsets....you would go to shift gears and the chain would bind in the rear cassette between two gears...

I still stand by you needing a wider chain or 9spd cassette.:corn:

nope dude said I needed a new crank or a crank that would work with an 8 or 9 speed cassette. Chain's getting stuck between the gears on the crank not the rear cassette.

 

[Boonie Buster]

Sheldon Brown's Website:

Chain suck

Chain suck occurs primarily when downshifting under load from the middle to the smallest chainring. The bottom run of the chain may not immediately disengage from the middle ring, and can get carried upward until it wedges betwixt the chainwheels and the right chainstay.
This jams the crankset. Since you probably wouldn't have been shifting to the granny if you weren't already climbing, the sudden lock-up of the drive train deprives you of what little momentum you had, and you are very likely to stall and fall.
Chain suck is commonly caused by bent chainring teeth, dirty chains, or, occasionally, burrs on the teeth of new chainwheels. Jonathan Levy has an extensive Web site about Chain Suck

 

[Boonie Buster]

nope dude said I needed a new crank or a crank that would work with an 8 or 9 speed cassette. Chain's getting stuck between the gears on the crank not the rear cassette.

You can run 1/2/3 chainrings on the front crank with multiple spd rear cassettes... I don't think a new crank is the problem, unless it was SOMEHOW manufactured wrong.:eeek:

 

[Glenn]

And if it was a demo bike before you bought it, it should be working right.

 

[Toyotanut]

And if it was a demo bike before you bought it, it should be working right.

You can run 1/2/3 chainrings on the front crank with multiple spd rear cassettes... I don't think a new crank is the problem, unless it was SOMEHOW manufactured wrong.:eeek:

Well, guy at bike shop in Monroe showed me a crank for an 8 or 9 speed and the chain rings were alot closer together than the one that's on mt bike now.

As far as it being a demo bike, it could have had this crank put on for photo shoots or looks, while they took it around to the bike shows. There were no signs of it ever being ridden when I got it.

 

[Boonie Buster]

Well, guy at bike shop in Monroe showed me a crank for an 8 or 9 speed and the chain rings were alot closer together than the one that's on mt bike now.

As far as it being a demo bike, it could have had this crank put on for photo shoots or looks, while they took it around to the bike shows. There were no signs of it ever being ridden when I got it.

Do you have a pic you can send me? I'd like to see it. :corn:

 

[Toyotanut]

yeah, i'll try and get one with my phone. What do you want one of? looking down on the chain rings? or something else?

 

[64FJ40]

IIRC, the 9-speed cassette uses a narrower chain (HG93?), but the 8-speed cassette should be standard width (HG70?).

Maybe you just have the wrong chain?

 

[Toyotanut]

IIRC, the 9-speed cassette uses a narrower chain (HG93?), but the 8-speed cassette should be standard width (HG70?).

Maybe you just have the wrong chain?

Not sure on chain size, but I know the little bit of looking I did said that the cranks for an 8 spd would work with 9 spd.