the 'there's no such thing as a stupid question' bike maintenance thread

devonp

cletus wrote: »

You might need to be less gentle...

yes maybe... but its a carbon steerer :eek: so i want to be as gentle as possible



maybe i should squirt some degreaser down the head tube and up from the btm part as well... ??

Type 17

If you've removed the compression ring (the v-section ring with a split, that fits just above the top bearing) and all other possible impediments, then get an assistant to hold the frame while you hold a piece of scrap wood over the top of the fork steerer and hit it harder with your rubber mallet (the wood is to stop the sharp top of the fork steerer from damaging the mallet more than necessary - or you can use the wood with a regular metal hammer).

Tony04

Try something like wd40 gt 85 or weldtite tf2 spray over degreaser.
Have you taken all the headset bits out like spacers etc.

A photo might help

devonp

yes... less gently did the job ...
its filthy up there... a lot of cleaning before the new one is fitted



should i grease the new bearings....read somewhere about avoiding gettting grease on the steerer tube ..can cause the carbon to swell..?


anyway i'll get to cleaning first...

Tony04

Any bike specific grease is designed for use with carbon of course you should grease it if you want to make it easier to take off the next time you replace it. Grease all the metal parts

devonp

took a bit of work to get the bottom bearing out...


anyway i presume the chamfered inner race of the btm bearing should face down towards the wheel ? it slides onto the fork fine and rotates nicely



also i have 2 types of grease...
1. weldtite lithium grease whitish
2. RSP bearing buster grease more browny cremey colour


any preferences ?

Type 17

devonp wrote: »

took a bit of work to get the bottom bearing out...


anyway i presume the chamfered inner race of the btm bearing should face down towards the wheel ? it slides onto the fork fine and rotates nicely



also i have 2 types of grease...
1. weldtite lithium grease whitish
2. RSP bearing buster grease more browny cremey colour


any preferences ?

Yes, chamfered side down on the bottom race, and chamfered side up on the top race.

Cartridge bearings like these are lubed inside already, so grease is only required to prevent corrosion (in the frame's bearing seat/on the outside of the cartridge bearing) from water ingress. In cases like this, it doesn't really matter which type of grease you use.

devonp

one last biggie question...


just came across a you tube video where a press tool was use to insert the bearings ???


top bearing seems fine to push in by hand but the btm bearing is very reluctant to get into the head tube :(


LBS time ??

Type 17

Is the frame's seat clean? Even a bit of grit will jam everything up.

Likewise a small burr or ding will stop the bearing going in smoothly (but can be filed away carefully, if required)

Is the old bearing exactly the same diameter? Some headset bearings differ in size by only 0.1mm (Why, frame manufacturers, why?!) and even this small a difference is effectively the wrong size. Hold the outside of the old and new bearings between your fingers and see if they feel identical or a tiny bit different.

devonp

had to hammer the old btm bearing out and it broke.....inner race and balls and seals ...could the outer race still be stuck inside the head tube ?


the new bearing will go in but only about 2mm then it jams..

Type 17

Pic of the lower seat of the frame required...

devonp

hopefully this uploads

devonp

hopefully again

devonp

one last try maybe better image...

devonp

with the image ..

Type 17

The first pic (IMG_1487) does appear to show that the outer race of the cartridge bearing remains in the frame, so it needs to be removed.

On an older, steel frame you could tap it out with a long screwdriver or similar, but it's harder on an aluminium or carbon frame (and a bit more dangerous on a carbon one) because the walls of the head-tube are thicker and block access in most cases.

Your LBS will have a tool like this for driving it out straight (it's driving it out crookedly that's the danger here - can lead to ovalisation on a metal frame, and to possible cracking on a carbon one).

If you have the facilities, you can make a tool like the one above by cutting and spreading the end of a piece of pipe (not copper plumbing pipe - too soft)

devonp

cheers...the more i look at it with a flashlight ...i think the race is still in there

rayman1

Same thing happened to me with a 5 year old Carbon Giant Defy. Bottom bearing fell apart on removal but the outer race was corroded into a metal socket.
Had to bring it into my LBS a Giant Dealer and they managed to remove it with great difficulty.
Lesson learned and now I remove and regrease it annually.

devonp

ok, not sure if there is a metal recess/seat for the bearing or just bear carbon..?

8valve

There should be some form of metal insert built into the headtube that mates up perfectly with the new bearing when inserted into it?

CramCycle

Tony04 wrote: »

Any bike specific grease is designed for use with carbon of course you should grease it if you want to make it easier to take off the next time you replace it. Grease all the metal parts

Really? I was under the impression that many greases bikers might use are inappropriate with Carbon. Am I wrong?

rayman1

8valve wrote: »

There should be some form of metal insert built into the headtube that mates up perfectly with the new bearing when inserted into it?

It depends. My 2013 Giant Defy has a metal insert that the bearing race corroded to but with my 2016 Cube Attain Race the bearing fits directly into carbon so no chance of getting stuck.

mosstin

I have a Cannondale Super Six Evo which came with a bog-standard Aksium disc brake wheelset. I'm new to disc brakes so I'm looking to upgrade the wheelset - are all disc brake wheelsets compatible with disc brake bikes?

Type 17

rayman1 wrote: »

It depends. My 2013 Giant Defy has a metal insert that the bearing race corroded to but with my 2016 Cube Attain Race the bearing fits directly into carbon so no chance of getting stuck.

The Cube almost certainly has an aluminium reinforcement buried within the carbon - there's no way the bottom of a carbon head tube could take the loads/shocks without it (unless it was massive, to the point that it would add more weight than an alu reinforcement and ruin the aerodynamics/appearance)
Good design to bury it in the carbon fibre though, as the steel bearing shells react with the alu reinforcement in the presence of moisture, causing corrosion/jamming.

Type 17

mosstin wrote: »

I have a Cannondale Super Six Evo which came with a bog-standard Aksium disc brake wheelset. I'm new to disc brakes so I'm looking to upgrade the wheelset - are all disc brake wheelsets compatible with disc brake bikes?

You should confirm the axle type of the Aksium (I presume standard quick release with skewers, rather than through-axles), and also the width of the front & rear axles of them, and only look at new wheels with the same widths.

Axle widths are especially important with disc brakes - on bikes with rim brakes (and metal frames), you can get away with (but still shouldn't) putting wheels on with a few mm difference, but with disc brakes, if you stretch/compress the frame or fork even a few mm, the callipers will no longer be perpendicular to the axles, and you will get alignment problems (rubbing).

Tony04

If your bike has through axles on a road bike the standard is the exact same 12x142 12x100 so any thru axle road bike wheelset should fit.

If it has quick releases it most likely uses 5x135 in the rear 5x100 in the front. Alot of thru axle wheel sets come with qr adapters so you should be able to change it if you need so

dermabrasion

Question about 1 x11drives
I have a 1 x11, with an 11/28 cassette and a 42T narrow wide chain ring (GRX). The top end is obviously pretty limited.
I have a Bontrager Aeolus wheel set.
Question: Is it a big deal to change the free hub to an XDR on the bontarger? The plan would be to put a 3T 9/34 cassette on.

magicbastarder

the GRX RD comes in two versions - one with a 34 tooth max, the other with a 42 tooth max, so 34T should be fine. however, it has a min of 11 teeth, not 9.

Tony04

Shimanos derailleur capacity recommendations are known to be conservative but I dont know why you cant put a mtb 11-36 cassette or even a sram road 11-36 cassette on

dermabrasion

Thanks Lads
I know I can put a bigger cassette on like a 11-36, but its the top-end I was looking to change. Currently my chain ring is 42T, which on my 11/28 spins out when I hit around 48-50kph. The 3T cassette has a narrow range in the 28-40kph zone (ie.racing speed) but it has a bailout cassette for climbing. The simplicity of just changing the free-hub and cassette appealed.
So, if I stay with shimano, then I need to change both the chain-ring and the cassette to have a downhill gear and a climbing gear.
So, I could put a 46T with 11/34.