Creaky Cranks
 

I just started riding my 2006 Hardrock after allowing it to sit in the garage for a few years. I really only rode the bike as a commuter and started riding off-road a few weeks ago. I replaced the chain and rear cassette because of wear (chain slipping). Everything was fine for the first 4-5 rides. During the past 2 rides, however, I have a very loud creaking when the in the small, front chainring, when there is a load on the chain. The creak does not occur in the middle or large ring. Any ideas?

is it a creak or scrape?? only occurring on the small ring sounds suspicious, not a bearing issue or crank arm/spindle issue. I would look closely at your front deraileur. sometimes your chain line will be fine if youre on the small ring up front and the large side of your cassette but once you start into the smaller cogs (higher gears) the chain will rub the cage.

is it a creak or scrape?? only occurring on the small ring sounds suspicious, not a bearing issue or crank arm/spindle issue.

I would look closely at your front deraileur. sometimes your chain line will be fine if youre on the small ring up front and the large side of your cassette but once you start into the smaller cogs (higher gears) the chain will rub the cage.

And remember you're not supposed to ride on small ring/small cog or big ring /big cog. too steep of an angle

First of all get a chalk and blackboard and write 100 times "I rode my bike on the road".

Anyway, I'm hoping your problem is fairly simple. The innermost chainring is mounted using different bolts than the larger pair. If you're lucky, you have some loose bolts on that chainring, and tightening with a 5mm hex key will solve it.

If you're not lucky, it could be anything (almost). One thing to consider is that using the innermost chainring means the highest chain tensions, so things like a bad bottom bracket bearing, loose right cup, axle deflection on the rear hub, and many other drive train issues will appear first with the granny (or any time you stand on the pedals).

Say a silent prayer and check the chainring bolts, otherwise you may be in for a long diagnostic haul.

this. I really hope this solves it; we all do.

I had a buddy tell me that standing on the cranks when I ride hard isn't good if I want them to last?? Any truth to this?

Well, it's not particularly good for your knees, and it will put more force on the crank/spindle interface, but if there's not something wrong already, I doubt it'll do any harm, assuming you haven't got absolutely ridiculous amounts of leg strength.

Thanks for the reply, I think I might refrain from "standing on it" so much since I really like my ride and hate taking to the shop since things break when I look at them! :(

Well, like I said, if you stand and pedal hard a lot, what's most likely to end up in the shop is your knees, not any properly designed bike.

Absolutely not unless you weigh something like 400#s. Cranks have to be strong enough to handle strong or heavy riders standing when they climb a steep hill or sprint. They're built to handle this with ease, with plenty of reserve strength.

It might be a problem if an adult stands on cranks or pedals made for a child's bike, but anybody that tells you not to stand on your cranks might as tell you that riding the bike is bad for it.

Tighten up the nuts/bolts holding the crank arm to the bb.

For a given gear combination, standing gives more leverage and allows the knees to be straighter than if the rider were to stay seated, so I'd say it's better for the knees. ;)

That said, if you have dodgy knees, it's best to shift down if you find yourself needing to stand to keep going forward.

True, but it's better still for the knees if you use a lower gear and don't have to stand. I should've made that more clear, to be fair.

When I stand on the pedals, it's more like working out on a stair master or hiking up a steep hill. I don't grip the bars and pull up on them to create more force, I just use my weight over the pedals to lower them.

Sometimes my gears aren't low enough.

a few years back I had creak - out of the saddle uphill - narrowed it to the BB - campy Chorus - my LBS recommended Loctite 660 , an epoxy resin - put some on each side of the bearing, slide the cups on, let it cure overnight & next day no creaks - the 660 addresses the slippage between the bearing & cups under load.

this remedy worked for the Campy BB design - wouldn't apply to Shimano outboard bearing or the newer Campy ultra torque designs .

I just wanted to report back since this past weekend is the first chance that I've had to ride this bike again. I tightened the chainring bolts as you suggested and it certainly quieted things down quite a bit. While not completely silent it has reduced the creak by a good 85-90%. I need to give the drivetrain a through clean and lube and hopefully that will take it the rest of the way. This was absolutely a creak, not a rub. No cross chaining.

Thanks for the tips.

Sometimes minor corrosion will cause noise - the cure being to remove the chainring bolts, clean the surfaces and perhaps add a very small amount of anti-corrosion/lube to the surfaces - light lube, wd-40, etc.

It IS bad for it! lol. Wearing all these components out, replacing drivetrains, etc...

Kidding aside, FBinNY is right. The drivetrain can stand a lot, and cranks themselves can stand up to a lot and will not 'wear out'. They won't break either: I stand on the cranks/pedals on my kid's 16" bike all the time and they are fine.

The OP's problem sounds like chainring bolts.

OP here...back for more advice. This creak is certainly the chainring bolts. The problem is that they do not tighten completely. The outer bolt head has a 5mm hex but the inner part is completely circular so there seems to be no way of getting a tool on both ends to tighten (no hex, no slots). I can't remove the bolts as the entire bolt/nut assembly just spins. Any ideas? Drill it out and replace or is there a way to tighten these?

This is a cheap truvativ crank from 2006