If you don't have a micrometer to measure diameter on the parts, take a crescent wrench, adjust to the tube you are measuring, then place that over a ruler to gauge the diameter. Upvote this comment to help people!
Or buy a $10 or cheaper plastic vernier. I've had mine for at least 25 years, they're broken but I still use them. For super critical stuff I have a micrometer. The shifter trick is just too povo. Lol . 😆
I stopped riding 23 years ago when kids arrived, now my son and I are back into it- with old school and new bikes. Now a lot of the tech has changed- but Park Tool is still on top of it! I appreciate the great tutorials.
Migrating from a quill stem bike from '98 to modern steering tube assembly. This is perhaps the best instructional video I've ever seen on youtube about anything... terrific and comprehensive job!
evergreen tutorial for newbies like me...planning to buy stem extender to make my handle bar higher, but after watching this i just install the stem in down position..simple & save my money!
I recently purchased a bike with this kind of stem and had NO idea how it was put together, nor how to adjust things. This great video is so helpful, thorough and really well presented. Many thanks!
Really appreciate this series of professional bike maintenance videos from Park Tool! So hard to find a source of reliable expert information on the subject these days.
Many road bikes do not use the small 5 mm spacer under the top cap. The reason is the expander plug is put in and the extension bar then slides up 3-4 mm pass the top of the plug metal head. This allows for the bottom of the expander plug to protect the carbon steerer on the bottom and top bolts of the extension bar. Always use a 4 cm expander plug this way you can the 5 mm spacer, a smaller expander plug is really for slammed stems, also check the inside of the extension bar and make sure it is smooth and has no rough edges on the clamp hole area. I have seen tons of high end road bikes where there is a 4 mm gap on top and the cap tightens with no spacer underneath it.
Hi, thanks for this, really helpful for me as a beginner maintainer at 53! You are helping prove it’s never to late. The format, structure and commentary is ideal.
Thank you so much for your tutorial videos. Thanks to this one I was able to shorten my stem on my own - now my Cannondale CAAD 4 fits me way better. Of course I used Park Tool tools for doing it, they feel great!
Bonus tip to help make sure that steerer tube is tight: Place the front wheel snug against a wall and firmly (not violently) pressing down on the stem while sitting on the frame top tube. This should sit everything tightly before tightening the top screw.
Clear coherent explanation and procedure of how to complete this task. The down arrows. Could be from authors of the abundant; poorly conceived videos or bike shops attempting to limit knowledge.
Installation in written form: Set bike on ground, ensure full stack is entirely seated. Set stem height. Stem or spacers should be ~3mm above the top of the steerer tube. (For carbon forks, steerer tube MUST go entirely through stem. Use spacer on top to get the 3mm) Grease on topcap bolt, install. Snug down, tune later. (Carbon bars - put on assembly compound) Grease OR threadlocker on faceplate bolts. Thread in bolts. Tighten lightly but evenly according to stem design. Set bar roll, center bars. Fully tighten faceplate bolts (4-6Nm) in X pattern. Snug topcap down until there is slight resistance. Bars should turn with almost no resistance. If there is, loosen by 1/8 turn at a time. Straighten handlebars to fork. Snug pinch bolts. Test for play in headset by holding front brake and rocking forward and backward. Feel for play at headset. If there is play, loosen pinch bolts, tighten topcap 1/8 turn, retighten pinch bolts and try again. Tighten pinch bolts (4-6Nm).
Is there a rule of thumb for the space between the stem and the faceplate? After putting on a new stem my space is about 5 millimeters but the bolts are long enough to be quite inside the stem.
Hi ParkTool. I need some advice on my stem. I just bought a renthal apex stem. While installing to my rockshock recon fork, i realized it was too tight to enter. So I used a rubber mallet to knock it in. But after one ride, i noticed there is some play on the headset. Can i get an expert advice on what should i do?
It sounds like you may need to add another headset spacer. Loosen the fixing bolts on the stem, add the spacer then tighten the top cap and i'm guessing you will be off to the races. Hope this helps!
Question! At 7:02, the video has us adjust the top cap until there is little resistance. Then, at 7:38 we test the headset adjustment looking for play and if we have play, then we tighten it down a little more. Won't the tightening of the top cap to prevent rocking then increase the rotation resistance of the handlebars? It seems like the action to prevent one issue is simply going to cause a second issue.
You should be able to eliminate play without excessive resistance. It is preloading the bearing and is necessary to do. A loose headset can ruin a headset or in some cases a bike.
Check with your manufacturer for greased or non greased specs. Typically these are spec'd with grease but some models are spec'd dry. Very very few though. Typically only if Ti hardware is involved.
Quick Q - if adjusted correctly, with play removed - and accounting for correct procedure + 3mm gap, should the spacers be able to rotate (with high effort)?
I got a new race face chester stem... And a torque wrench... On the sides of stem is written that you need to tight bolts to 12 Nm (steer tube bolts). Im little bit confused because in the video you said that a typical effort is about 4 to 6 Nm. Thank you.
If the bolts were clean/dry, with nothing, grease is good thread preparation. You likely had an aerobic thread locker, installed dry. Run them as they are, without grease. The dry locker provides some prep for the thread.
My old stem had a little plastic spacer that filled the compression slot on the rear of the stem. It has two holes for the bolts to pass through. Is this just an optional, aesthetic thing? My new stem didn't come with one and I can't see any images of other stems using a spacer, they just have a gap it seems.
The reason for the stem or spacer to be above the steer tube is to allow the top cap to do is job. The top caps job is to pre load the headset bearings to get rid of any potential for play. If the spacer or stem is below the steerer then it will be near impossible to get a correct headset adjustment.
Can I leave more than 3mm between steer tube and the stem (stem above the steer tube), and by how much? My stem is too low and additional 5-7mm rise could be enough for me. Would that be a hazard? I could get the stem riser, but that is way too high even if I point the stem down.
More than 3mm is not advised. Its hard to say if or when you will ahve a problem going higher than the 3mm but it is not advised. It may be safer to look for a bar with a higher rise or a stem with a higher rise.
The video was very helpful, thank you. I have a question. Is it okay to have a gap of about half a centimeter in between your two stem pieces? I ordered the right size but they are not coming together around the handle bar with a tight seal.
@Park Tool Is there a desired steer tube length height? I'm 5.5" my new bike frame is 13" takes 700c wheels so, how high should my handlebars be adjusted to the steer tube?
Steer tube height is mostly personal preference. Longer will offer more adjustability. Shorter may give you the visuals or fit you are looking for. Just depends on your fit and where you need to be positioned.
@@parktool Hello there i need your help in something i have a question about my bike it’s a Scott ransom 910 2021 you see when ever i wash my bike with muc off soap and water i get a creeking sound from my headsets and it was so annoying that I couldn’t find what’s causing this till I opened the headsets and found out that when ever i wash it the grease from The headsets bearings fell of completely cause of the water and starts creaking like crazy but wait why the grease is dropping after i hose my bike its because it’s not a waterproof grease but that shouldn’t fix the problem that means i have to put fresh grease every time i wash my bike till I found out that the headsets that came with my bike from the factory it doesn’t has a washer completely like no washer whatsoever now my question is this and I think it’s the solution for my problem I’m willing to replace the headsets and the stem just to buy a headsets that has a washer i got In mind cane creek branch their the best I think anyway Since I have a square shape of headsets and square shape of spacers I’m forced to buy a new stem and a pare of new headsets that comes with a washer my only problem is that I don’t know if their is a measure I should take in min when ordering a new headsets with rounded spacers could you help me I really appreciate that thank you waiting for your reply thank
If the steerer is metal then the star nut has gone bad. Unfortunately it may be best to drill the head of the bolt out and then use a punch to pound the star nut out the bottom and replace. If the steerer is carbon then you may just need to use one size smaller hex key to tighten the expanding plug and then loosen the top cap.
4:45 I had some play cause my steerer tube was about 1/4" above my stem... I didn't think that this could cause it, but I was wrong! threw another spacer in the mix and problem solved!
Some stems have covers like that. Those covers should be able to be removed to allow access to the stem bolts. Send an image to tech@parktool.com if you would like a better idea on how to remove the cover.
Maybe a stupid question at 5:59: Are you applying SAC-2 fibre grip to the bolts (or is that your PPL-1 grease)? Wouldn't this increase the friction resulting in less axial tension? Meaning you need more torque to achieve the same tension - which is what you wouldn't want if one of the components is carbon? I thought SAC-2 would only be applied to clamp surfaces.
Sounds like you should grease all your stem bolts and tighten everything down. When the bike is built is the best time to check this over. After bike is built it should be checked on a regular basis.
@@MrStruggle0 thank you all... I just did this... noticed some play in the fork... I have the steerer tube sticking out about a 1/4 in, after I swapped out the stem. didn't think it would make a difference.. gonna order some more spacers today THANKS!
uncle freddie lol I made the same mistake, I would suggest doing it on the wheels so that the fork can kind of push itself in instead of you holding it (worked for me)
I can’t unscrew my top stem cap, it just keeps turning and turning and won’t completely unscrew.... any tips? I’m trying to eliminate all play in fork and headset
In case I change my stem from a long one to a significantly shorter one (e.g. from 100mm to 50mm) is excess cables' length going to affect brakes and shifters setting? Thanks to anyone who can answer.
