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@Calnago. During this step of the SRM crank installation, did you use any type of grease on the inside diameter of the BB cups, hirth joint or spindle screw?Calnago wrote:Ahhh... now getting to the fun stuff... up first is the SRM Campy 4 arm crank. This is absolutely in my mind the nicest piece of kit for a Campy install that you can get. It really does look like a factory crank, and not even a powermeter. I like the simplistic look, with no clunky add ons, batter covers, cutouts, etc. Just clean and simple, and ultra reliable... it does what it's supposed to do. And quite frankly, I think it looks better than the stock Campy 4 Arm cranks, because it doesn't have all that carbon webbing out from the arm. Clean!
Ok... but first I needed to flush out all the grease that SRM packs into the CULT bearings. Why they do this is beyond me. It pretty much negates the benefits of having CULT bearings in the first place. Campy CULT bearings are not intended to be packed with grease, at most just a couple drops of light synthetic oil is all you need or want. Here's how they now come from SRM...
So after a few minutes with this stuff...
I end up with what I want these CULT bearings to look like upon install, with a couple drops of light oil they spin like a dental tool...
Oh, the SRM crank utilizes a C-clip which is a little smaller around the loops that jut out from the cups in order to recess properly in the SRM shell without touching. Make sure you use the clip for the SRM install and not the standard clip that comes with the Campy Cups, SRM clip on the left...
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Spindle gets a light coat of grease simply to prevent corrosion.
Light coat of grease on the teeth of the hirth joint though they’re torqued so tight there shouldn’t be any movement there, but I just like having a bit of grease wherever metal makes contact with metal.
Then the hirth bolt itself. I usually use these days a bit of Morgan Blue Aquaproof Paste, but have used purple loctite (222) in the past. It’s just to prevent corrosion mostly but does keep things tight. Torque it down to 50Nm and done.
Trouble is, the top of this stem is notched, and you can't just slap an ordinary spacer on top. So, in order to use my own top cap, I would need to purchase the ProVibe "Spacer kit", which includes various spacers of the same shape as the top cap and one 5mm specially notched spacer that you would need if you wanted to keep any spacers above the stem (maybe for prefinal ride testing) or in my case, if I wanted to use my custom top cap.
Plus, I've always been averse to cutting the steertubes below the tops of the stem, unless the particular design requires it, and some do.
Anyway... here's how the finished product is supposed to look, using their proprietary top cap that comes with the stem...
But in order to do that, the steertube needs to be cut below the top of the stem edge... like this... Note: I would actually position the top of the steertube right at the minimum line, I just dropped it a bit for the photo to expose the "minimum" line so you could see it...
Ok, so after much deliberation, I decided I wanted to use my own top cap for a few reasons: 1) I just like it; 2) the steertube would have FULL contact with the entire clamping area of the stem; and 3) If I want to go to the stock cap supplied I could just cut a couple more millemeters off, but I can't add any back on after the fact. So, here's how it sat after replacing the old stem with the new one but before any cutting...
And since I can't just use a normal spacer on top, I had to buy this special "spacer kit"... note the one spacer on it's side, the special 5mm one with the notch in it that fits into the notch in the stem... there's really no way around purchasing this kit if you want to add a spacer...
So, I was actually hoping to get away without a further cut in case I decided I wanted to go back to the old stem which has about a 4mm higher stack height, but when I put the special spacer on top it ended up like this, and I knew that the top of the steertube wasn't recessed enough to allow for the top cap and it's lip underneath plus enough of a gap to apply the preload...
If I did try to put the top cap on, it would bottom out on the top of the steertube and no preload would be able to be applied, plus there'd be an unsightly gap between the spacer and the top cap.... like this....
So, pull it all apart to cut just a couple millimeters more off, put it back together to get it right... full stem contact with the steertube and just enough protruding to provide a "placeholder" for the spacer, but still leave enough space between the top of the steertube and the bottom of the top cap to be able to apply the appropriate preload....
And finally.... place the custom top cap on, apply the preload, make sure everything is straight and aligned with the front wheel direction, and lock it down....
Here's some other profile shots witht the revisions in place... sits nice....
I also really like it when stems have wide full coverage one piece face plates. It just distributes the clamping force so much more evenly that two separate thin pieces could ever do, and helps keep things really stable. This combo is really solid...
And finally, I thought I'd just show a couple different tops caps to present why some top caps may require a spacer above the stem moreso than others. For instance, the top cap on the left which is what I'm using has about 2-3mm of recessed lips underneath the first lip that would seat on the top of the spacer, or stem if there were no spacers. So, in addition to those 2-3mm of top cap that sits below the top, you also need a little space to provide the preload on the headset bearings. So, you can quickly see that even a 3mm spacer would not provide the space in this case for me to both use this top cap AND have the stem fully clamping on the steertube.
Now, look at the white top cap, the stock Colnago cap that is supplied with the bike... it only has a lip of about 1mm that would sit below the top spacer or the stem top. Therefore, you could get away with sitting this cap flush on "most" stems with the top of the steertube only 2mm below, which should be just fine while still allowing a small gap to apply the preload. That last little 1mm ring of carbon steertube is just the portion I had to cut off to get the space I needed. All good now, and it seems like it's going to work out just fine for me....
Sheesh... that's a lot of pics etc for just a steertube trim, but I thought this new stem is unique enough (especially in the way the top cap sits etc.), that I'd show it here. And if you're using an electric wired drivetrain, it's got some nice channels in it to hide the ugliness of the exposed wires, especially if used in conjunction with their compatible bars.
Cannondale Supersix 2008 (weight: 7.3kg)
B'twin Triban 540 (in bits)
Vitus "Benotto" 979 (weight: )
I really love this build, and thanks to you I have mailed SRM for the right C Spring for my SRM ( never got an answer though. ). I also love the way you use your ceramic bearings without grease or rubber seals because I never would. Maybe cause of the weather here in the Netherlands , but I have my C Bear Ultra Torque bearings and C Bear Pully wheels double sealed.
But why a -17 degree stem with 2cm of spacers . I think a -6 degree stem would look much better with just 5mm of spacers.
PinaRene wrote:But why a -17 degree stem with 2cm of spacers . I think a -6 degree stem would look much better with just 5mm of space
I think the -17 looks good being in line with the top tube. There would still be spacers with the -6, so you might as well embrace them.
Cannondale Supersix 2008 (weight: 7.3kg)
B'twin Triban 540 (in bits)
Vitus "Benotto" 979 (weight: )
I do really like the design and aesthetics of the stem however, as it really works well with the C60 tube shapes. And it's solid.
On the SRM c-clip... how'd you have your SRM installed without the proper C-clip... are you just running it wihout? Because the regular one just doesn't fit. I just had to reinstall a terrible build for someone who had an SRM, where the left/right Ultratorque cups were on the incorrect sides (left was on right, right was on left). Wavy washer was omitted completely and the clip was now on the left side. But the the right cup (which was now on the left side), was actually gouging into the left crank as it "spun". It was a mess. I figured they must have reversed the cups from left to right because the standard c-clip wouldn't fit on the drive side with the SRM. They probably felt quite proud of their "modification' but it was a royal mess.PinaRene wrote: ↑Thu May 17, 2018 11:16 pmI really love this build, and thanks to you I have mailed SRM for the right C Spring for my SRM ( never got an answer though. ). I also love the way you use your ceramic bearings without grease or rubber seals because I never would. Maybe cause of the weather here in the Netherlands , but I have my C Bear Ultra Torque bearings and C Bear Pully wheels double sealed.
I never "grease" the CULT bearings... you may as well not even have them if you do. Just a couple drops of very light synthetic oil is all it needs or wants. SRM has been a bit at odds with Campy on this, and if you get an SRM campy crank you will find the CULT bearing packed with grease now. I received my first one with no grease at all, as you would get with a SR crank from Campy, then I've received one which had grease in the drive side bearing only (added by SRM), but the left bearing no grease, then I have received one with grease on both bearings. With the CULT bearings I like to run them with just the light oil, as Campy intended. I do leave the seals in the cups now, however, unless the bottom bracket is quite closed up from grit from underneath. When I built my C60, I figured that slot in the bottom of the BB was not in a spot that stuff could really get thrown up in there, and on normal paved roads it's fine, but after riding some crushed gravel paths with it I noticed that gritty fine gravel was indeed making it's way through that slot under those conditions, so I recently put the seals back in the cups of the BB, but still just use a couple drops of synthetic oil in the bearings themselves.
I managed to fit the C Clip - but I have to try and find out if I have have the SRM one or a standard one. To get the C Clip in was a real PITA , and to get it out was even worse , but I've got it out with a 4mm hex key. So next time when I take it apart for maintanance I will re-oil the bearings with a little ceramic oil from R2 bikes ( German store ) and see how that runs. Now they are greased... as I bough them while they were mounted on a Record crank. Took the bearings off and mounted them on my SRM crank. The Record crank now runs on standard bearings.Calnago wrote: ↑Fri May 18, 2018 6:47 pmPinaRene wrote: ↑Thu May 17, 2018 11:16 pmI really love this build, and thanks to you I have mailed SRM for the right C Spring for my SRM ( never got an answer though. ). I also love the way you use your ceramic bearings without grease or rubber seals because I never would. Maybe cause of the weather here in the Netherlands , but I have my C Bear Ultra Torque bearings and C Bear Pully wheels double sealed.
On the SRM c-clip... how'd you have your SRM installed without the proper C-clip... are you just running it wihout? Because the regular one just doesn't fit.
I never "grease" the CULT bearings... you may as well not even have them if you do. Just a couple drops of very light synthetic oil is all it needs or wants. SRM has been a bit at odds with Campy on this, and if you get an SRM campy crank you will find the CULT bearing packed with grease now.
As for the c-clip, if you were able to fit the SRM over it during install, then I would believe you have the correct clip. I’ve got it down as to install and removal , but certainly not with a 4mm hex key. I use a teensy flat screwdriver through the crank arm hole (using a little flashlight to make sure it’s positioned correctly, pull up the c-clip, then rotate the crank very slowly so that it forces the screw driver (and edge of the clip) just outside of the hole it sits in. Same for the other side, then easy to remove.
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