S40 headset keeps getting loose....any suggestions?

Kenneth

Well-Known Member
a month or so ago i noticed that the headset was loose. I tightened it a few times but it was still getting loose.so took it apart cleaned everything and re-greased the bearing. after resetting it all it took a couple of tries to get it tight enough, but now its a little loose again. What is the normal amount of time and or miles one should be able to ride before this loosens up? Could the bearing be bad causing it not to stay tight?
 

dtseng

Well-Known Member
Tighten the two screws on the stem. Make sure the bearings are installed correctly, not upside down. The head set will become loose if the semi-integrated bearing cups are not pressed all the way in. S40 is an expensive high class bike, please don't use cheap headset with loose ball bearings. Use those with sealed cartridge bearings.
 
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Kenneth

Well-Known Member
I will have to get the star nut checked , i had not thought of that. the bearings are the ones that came with the bike... Cane Creek i think
 

Jeremy S

Dude
The star nut + cap bolt are just to preload, they should not hold anything together while you’re riding. The bottom part of the boom clamp, where attached to the steerer tube, is what should be holding the headset down. Make sure that’s tightened, and that you have the proper spacers on the steerer tube such that the clamp extends a bit above the steerer tube (about a millimeter I believe) before the cap goes on.

(1) Loosen boom clamp from steerer tube.
(2) Tighten cap bolt so that headset (just) has no play.
(3) Tighten boom clamp on steerer tube.

After that, you could loosen or remove the cap bolt and it wouldn’t matter.
 
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jond

Zen MBB Master
Plus one on Jeremy.

Must have small spacer between stem boom clamp and headset.

Loosen stem bolts x 2 .

After ensuring condition and correct orientation/placement of top bottom headset bearings you could be able to tighten cap bolt TEMPORARILY to the point where steerer movement feels slightly notchy Indicating star nut is unlikely to be moving. Even if it did subsequently it won’t ,matter as noted by Jeremy stem boom clamp holds all. Make sure you back cap off so steering is free don’t want to overload bearings or bugger the race

From memory I think the bearing cups are integral and not glued so they can’t possibly move.

Therefore your stem is most likely the culprit and is too loose on the steerer tube.
 

dtseng

Well-Known Member
I just watched Robert's video on assembling S40 frame set. Congratulations! S40 comes with cartridge bearing headset. The two previous diagnoses are probably not correct. The star nut would bite into the inner surface of the aluminum steer tube and therefore should not move. If the two stem bolts are not tightened sufficiently, not only headset will become loose, the handle bar will be out of alignment also. We therefore come to the 3rd diagnosis: the bearings are not installed correctly. The general rule are: the tapered inner edge of the cartridge bearing should mate with inner race, while tapered outer edge (if there is tapered outer edge) should face the bearing cup. Since the bearing balls do not come in contact with the inner races, both are made of softer aluminum alloy and are not complete rings (both have a gap). First you install the crown race with your finger (since there is a gap, no need to slam it down with a steel tube). The upper bearing with tapered inner edge should facing up. If these are not installed correctly, the headset will become loose.
 

dtseng

Well-Known Member
I travel quite often with my bikes. I need to disassemble the bike to be able to hand-carry it into high speed train or subway. The headsets with cartridge bearings are really godsend. My DF road bikes are around 7 Kg and the frames have Ritchey type device. Assemble and disassemble the bike only need 3 Allen keys. To prepare for flight, I remove the spokes and hubs and pack the wheel rims in a paper box, the rest of the components go in the luggage with my clothes. I am designing a MBB with these features for touring to avoid airline excessive charges.
 

Gary123

Zen MBB Master
I travel quite often with my bikes. I need to disassemble the bike to be able to hand-carry it into high speed train or subway. The headsets with cartridge bearings are really godsend. My DF road bikes are around 7 Kg and the frames have Ritchey type device. Assemble and disassemble the bike only need 3 Allen keys. To prepare for flight, I remove the spokes and hubs and pack the wheel rims in a paper box, the rest of the components go in the luggage with my clothes. I am designing a MBB with these features for touring to avoid airline excessive charges.
You may be the only person in the world who removes spokes and hubs for travel.
 

dtseng

Well-Known Member
You may be the only person in the world who removes spokes and hubs for travel.

Lol, may be. What I was trying to say was that Kenneth had persistent headset becoming loose, but he did not mention that his handlebar becoming out of alignment. Therefore, I guess that his problem might not be due to the stem bolts not tightened sufficiently. On carbon forks, I would use torque wrench to tighten the stem bolts. If the cartridge bearings are not installed correctly, the headset will always be loose even if the stem bolts are tight.
 

jond

Zen MBB Master
Lol, may be. What I was trying to say was that Kenneth had persistent headset becoming loose, but he did not mention that his handlebar becoming out of alignment. Therefore, I guess that his problem might not be due to the stem bolts not tightened sufficiently. On carbon forks, I would use torque wrench to tighten the stem bolts. If the cartridge bearings are not installed correctly, the headset will always be loose even if the stem bolts are tight.

Lol Yep that’s what we said in checking correct orientation of bearings. Pretty easy to make mistakes if you don’t know and don’t follow instructions. But if Kenneth did then it’s loose stem or incorrect pre load. Simple. For a wheelbuilder in an airport. Lol. That really is amazing.

Kenneth is probably a mechanical engineer and lubed the stem fork clamp area. Lol.
 

jond

Zen MBB Master
Sorry but tightening the clamp on the steerer tube does nothing to align the handlebars.

Yep it’s not a df. It’s a yummy cruzbike I want one please my darling wife s40 cause seven is lucky but an odd number of bikes eight days a week.
 

Kenneth

Well-Known Member
Ya'll are funny.....
So no the handle bar don't come out off alignment.
I tried getting it checked out at the bike shop but its difficult because they don't want listen very well when I talk about how the S 40 works. They said the star but was fine but their was still a bit of play in the headset when they got done. I talked to a second mechanic at the same place and he checked and retighted it all. He asked if I had used a tool to seat the bearing in the first place because that could be an issue. I told him I didn't remember doing that but I'd bring it back later after I checked into it. I checked the video by Robert and he doesn't mention using a tool to set the bearings. Am I correct in my understanding that these bearing don't require a special tool to set them? You all mentioned preload, is it possible I just never quite tighted it enough to accomplish that correctly? Regardless as of right now it seems good but the test will be in a few days.
 

MariposaLand

Active Member
I don't have much experience with the S40 headrest. I put it on and leaned back against it with my bike helmet on and felt very odd so I took it off. Is there a secret I am missing?
 

super slim

Zen MBB Master
Lol Yep that’s what we said in checking correct orientation of bearings. Pretty easy to make mistakes if you don’t know and don’t follow instructions. But if Kenneth did then it’s loose stem or incorrect pre load. Simple. For a wheelbuilder in an airport. Lol. That really is amazing.

Kenneth is probably a mechanical engineer and lubed the stem fork clamp area. Lol.
A good Mechanical Engineer (especially one born in South Australia, NOT NSW!) would NEVER add lubricant to a clamped area, where you want the maximum friction between surfaces!!!

Have you got a 2 to 3 mm gap from the top of the steerer tube to the top of the spacer
as per the photo (at the end of the article) in the Bikeradar guide, so the inside of the cap does not touch the top of the steerer tube, and stop any preload occuring!
https://www.bikeradar.com/gear/article/how-to-service-a-headset-and-replace-headset-bearings-22225/
 
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Kenneth

Well-Known Member
I don't have much experience with the S40 headrest. I put it on and leaned back against it with my bike helmet on and felt very odd so I took it off. Is there a secret I am missing?
I don't use a head rest, but there threads that discuss there use on the forum.
 

Trekster

Member
a month or so ago i noticed that the headset was loose. I tightened it a few times but it was still getting loose.so took it apart cleaned everything and re-greased the bearing. after resetting it all it took a couple of tries to get it tight enough, but now its a little loose again. What is the normal amount of time and or miles one should be able to ride before this loosens up? Could the bearing be bad causing it not to stay tight?
I'm really discouraged to hear the headset on the S40 is coming loose after just a few miles of riding. A few years back I had the EXACT same problem with my Quest. At the time I tried ALL the recommended fixes; and nothing helped. Although I liked riding the bike, I eventually returned it for a partial refund. Recently I was very interested in obtaining one of the new S40s, but if headset problem is still there; I will not be ordering. Sad... :(

Does anyone know if the Headset Bearing/Assembly on the new S40 is the same as what was on my Quest from several years ago?
 
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Kenneth

Well-Known Member
I'm really discouraged to hear the headset on the S40 is coming loose after just a few miles of riding. A few years back I had the EXACT same problem with my Quest. At the time I tried ALL the recommended fixes; and nothing helped. Although I liked riding the bike, I eventually returned it for a partial refund. Recently I was very interested in obtaining one of the new S40s, but if headset problem is still there; I will not be ordering. Sad... :(

Does anyone know if the Headset Bearing/Assembly on the new S40 is the same as what was on my Quest from several years ago?

The headset issue was resolved. I didn't tighten it correctly when I built the bike it seems, because after I had the bike shop tightened it has been fine.
My S40 has been great and I don't think you have anything to worry about.
 

Trekster

Member
Very relieved to hear there is NO REAL headset problem. Glad you found the root of the perceived problem and got it fixed. I think the S40 is something that could be in my future. Thanks for the update, Kenneth.
 
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