[warek]

Hi there

Bought a new fork last year and a new headset, for my road bike, which was professional installed. I have about 6 cms of carbon spacers below stem and 2 cm of alloy spacers above stem.

Stem continously comes loose, you hear rattles over rough sections of road and when stopped if you lock front brake and rock bike you will have movement in headset.

I loosen 2 stem allen keys, tighten stem cap bolt,(usually about 1/4 of a turn), retighten stem allen keys, check for movement and it is perfect for about 500 kms then I have to do it all again.

I notice that the external diameter of the carbon spacers below the stem varies by about 1 mm and the widest one is directly below the stem. I also notice that I can manually rotate all of the stem spacers by hand when I have tightened the stem.

Am I not making it tight enough?
Or could the spacers be a problem?
Other thoughts?

Thanks for any input
Kevin

 

[Mike T.]

Remove the top cap and tell us how far down below the top of the spacer the top of the fork steerer is. It must be about 3mm below to allow the cap to preload the headset.

I think that 2cm stack of spacers over the stem is too much. 5mm would be about right but the steerer will have to be cut down - unless you put the excess spacers under the stem but then 6cm is too much already.

It could also be that you're not tightening the stem bolts enough. The torque value might be printed on the stem.

That comment "which was professional installed" give me the shivers.

 

[Apexrider]

You might also check if the expander is properly tightened, should be about 7 nm. 6 cm spacers below the stem is too much and might even be dangerous if your fork has a carbon steerer.

 

[danl1]

It sounds like you are bottoming out your adjustment. Depending on the details, that could be because the steerer is a little bit too long, or because the compression nut was not installed well and has risen in the steerer.

To check, take the adjusting (top) bolt out and remove the cap. (don't loosen the stem bolts.) The top of the steerer should be a little below the top of the highest spacer on top (or the top of the stem, were it on top.) If there's not a gap, some filing / sawing is in order.

If there is a mm or two for adjustment, you're probably just having trouble with the compression sleeve sliding within the steerer tube. I've had that problem before, and taking it out, cleaning the inside of the tube with alcohol, and re-installing carefully took care of things.

You also might not be tightening the stem clamp bolts enough; but I hesitate to say that unless you are willing to get a torque wrench (or at least one of the cheap torque keys) to be sure to do it right.

If this is a carbon steerer, it's too long and really should be cut down. If it's steel or aluminum, you won't have the compression nut problem, but you might have some grease making the stem clamp slide - though that shouldn't really matter.

based on what I'm hearing, I'll agree with others that there's a distinction between "paid to do it" and "professional."

 

[Mike T.]

I'll agree with others that there's a distinction between "paid to do it" and "professional."

At least I was trying to be diplomatic

 

[warek]

A bit of background on headset

Hi there

I was having some work done om my bike by a custom frame builder and he said there had been some problems with some Chris King headsets. As I had a replacment one in my collection of spare parts, I asked him to install it for me.
He then suggested that teh original carbon fork has been on the bike since 2005 and I had ridden 50000+ kms, that it could fail at any time and he had a Columbus replacement in stock. Because he was changing the headset, and I was having a few backaches I thought that getting a taller fork would be a good idea so got both new fork and new headset.

To answer some previous comments the fork has a carbon steerer, and I would be happy to reduce the 2cm above the top of the stem and 1 cm below the stem.
I would be reluctant to cut the stem myself in case I messed it up and did not cut it square or took off the wrong amount. How much steerer is the optimum above the top of the stem?
Is it a basic job for a local bike shop?

Thanks

Kevin

 

[mikerp]

Hi there

I was having some work done om my bike by a custom frame builder and he said there had been some problems with some Chris King headsets. As I had a replacment one in my collection of spare parts, I asked him to install it for me.
He then suggested that teh original carbon fork has been on the bike since 2005 and I had ridden 50000+ kms, that it could fail at any time and he had a Columbus replacement in stock.

Amazing how that works out.
What was the supposed issue with the CK headsets? Was he offering you a replacement as well?

 

[Mike T.]

I was having some work done om my bike by a custom frame builder and he said there had been some problems with some Chris King headsets. As I had a replacment one in my collection of spare parts, I asked him to install it for me.
He then suggested that teh original carbon fork has been on the bike since 2005 and I had ridden 50000+ kms, that it could fail at any time and he had a Columbus replacement in stock. Because he was changing the headset, and I was having a few backaches I thought that getting a taller fork would be a good idea so got both new fork and new headset.
To answer some previous comments the fork has a carbon steerer, and I would be happy to reduce the 2cm above the top of the stem and 1 cm below the stem.
I would be reluctant to cut the stem myself in case I messed it up and did not cut it square or took off the wrong amount. How much steerer is the optimum above the top of the stem?
Is it a basic job for a local bike shop?

All very suspicious but then we weren't there.
My backache was cured partially through lowering my stem and going from a 100mm to 130mm stem but then my problem was diagnosed properly - by a Physiotherapist.

But back to your steerer. You need to read up on steerer shortening. Both Chris King and Park Tool will have the definitive guide. I gave you the optimum steerer length in my previous post. Whether it's a job for a LBS depends on a couple of things -
1. Their ability to do a proper job other than just be willing to try at your expense. Don't confuse "willing to work for money" for "professional wok promised". There are too many horror stories.
2. Your mechanical expertise and ability to follow instructions.

I use an automotive worm-drive hose-clamp as a cutting guide. I also have a carbide grit hacksaw blade too, meant for cutting carbon fibre, but others manage with a very fine hacksaw blade and some masking tape around the steerer. Remember - measure 3x and cut once. Correction - never measure a steerer as mistakes can be made. Gauge it instead from the chosen (and installed) headset, spacers and stem. BTW it's a good idea to have a short spacer over top of the stem - maybe a 5mm one at most.

 

[wim]

My backache was cured partially through lowering my stem and going from a 100mm to 130mm stem but then my problem was diagnosed properly - by a Physiotherapist.

I keep mentioning this approach (at least as an experiment) to people who are convinced that the solution to their aches and pains on the bike is yet another round of a "more upright" modification. But I always get the thousand-mile stare as if had recommended self-flagellation with birch-tree switches after the morning shower.

 

[Mike T.]

I keep mentioning this approach (at least as an experiment) to people who are convinced that the solution to their aches and pains on the bike is yet another round of a "more upright" modification. But I always get the thousand-mile stare as if had recommended self-flagellation with birch-tree switches after the morning shower.

I upturned my stem in a desperate attempt to cure 50 years of cycling-related backache. It didn't help one iota. I've now spent nearly three years with a wonderful Physiotherapist and one of the first things she did was to video-record me on rollers. As well as many many exercises and therapies, one of the changes was the stem angle, height and length. I'm now much more stretched out - and backache free for the first rides in 50 years. A flippin' miracle.

 

[wim]

I'm now much more stretched out - and backache free for the first rides in 50 years.

Wished people would at least cautiously consider evidence like this. I'm so tired of hearing "need to be more upright and closer to the bars" from people whose knowledge of human anatomy is cursory at best.

 

[Mike T.]

Wished people would at least cautiously consider evidence like this. I'm so tired of hearing "need to be more upright and closer to the bars" from people whose knowledge of human anatomy is cursory at best.

Oh I get the theory of "If your back aches when you bend over on the bike then bending over less will equal less backache". But that's too simplistic. At the same time, I changed my forward bend from the lumbar area (L4/5) to my hip and my pelvis is now rotated forward & down when I ride. That lengthened my upper body and it needed a longer reach. Of course months of adaptation and specialized core exercises and side-to-side muscle strength & flexibility balancing went into it also. That's why no-one can get a diagnosis or diagnose anyone through the internet. It makes me laugh when I see them (every month) try.

 

[Cinelli 82220]

it could fail at any time and he had a Columbus replacement in stock

How convenient. For him, not you.

You should post a pic of your bike, or one with you on it. I'm curious what kind of fit your custom builder has you on that needs 6 centimetres of spacers below the stem.

 

[Peanya]

That's why no-one can get a diagnosis or diagnose anyone through the internet. It makes me laugh when I see them (every month) try.

I'm partly guilty of this too. I'm also guilty of assuming many people have the same flexibility issues I do, when they can't get a good fit. Regardless, I'm still of the school of thought that many fitters don't take flexibility into account when doing a fitting.