Cannondale SuperSix Evo4

[johnpuga1982]

It might be the top cap binding with the expander, it already happened to me that when I wanted to release the top cap it went away with the expander.

BobbyB had a similiar problem to you. If you look at the bottom of page 152 he mentions the problem. The conversation continues on page 153, 162, 163, and 164. Not sure if it continues past page 164.

My recommendation, buy a new expander plug, install it, and be done with that bike shop. If the new expander plug does not adhear to Cannondale's torque specifications there may be something wrong with the carbon steerer. Again, due to the initial installation of the expander plug.

New expander plug: https://www.cannondalespares.com/Cannon ... il/3-49447
New top cap and compression bolt: https://www.cannondalespares.com/Cannon ... il/3-49440

Thanks for the info again. Just to clarify, this was a different shop I took the bike to, a local shop Vs the online retailer where I got the bike from. This was a new expander plug (as my original one also had the Conceal bolt stuck on it) installed by the local shop, and after the steerer was cut (30mm taken off). So for this to happen again is odd. The new plug does have the little bands that help keep it together, and I think the cap may be stuck again but will need to confirm.

You could be right, maybe the steerer is out of tolerance and the recommended 4Nm doesn't hold the plug in place, or the inside of the steerer isn't the right shape and the plug can't grip it enough. But the plug goes into the steerer ok so can't be that far off. I'll try go back to them next week to try figure out what's going on.

Hi Bobby, this has happened to me twice already. The problem i think is that the owners manual calls for loctite on the top cap bolt threads and imo that is a mistake. When you go to loosen it the loctite does not break free and then the whole thing just threads out and the bottom piece falls into the frame! Its very annoying and I think if you make sure to use no loctite then all should be good. The issue is then you should be checking the topcap on a regular basis to make sure it is not coming loose and your preload is set properly. Not the best design to be honest but hopefully it works ok if you omit the loctite. Good luck! Putting back together the delta compression plug after its come apart is sort of like a jigsaw puzzle.....not very fun.

So you would grease the top cap threads. Should I also grease expander plug bolt? anything else? Your advice is to put grease on Momo stem bolts as well? I only use loctite or anti seize on these bolts... so grease? What about carbon paste inside the steerer?

I use grease on all my bolts. These bikes are basically race cars that need to be maintained on a regular basis. I find loctite too much of a hassle for something that needs to be checked periodically. The grease acts as an anti-seize on the bolts.

Actually I have 2 top caps, one came with the frameset and one with Momo bars. I might try the 2nd one. My expander is the black one. I can see there is black one (K35063) and silver one (K35051). It seems the black one is the newer one as it has the higher number in product code?

BobbyB talks about his experience with two different top caps.

Thanks all for the info and experiences. Good (well, not good ) to hear I'm not the only one who has had this issue. A few things worth mentioning:

- my first conceal top cap didn't have any locktite on it. I don't think the current one has any either, but can't be sure yet.

- haven't got the current Conceal bolt off yet. The first one I couldn't get off. It was incredibly difficult to grip the expander plug screw/bolt as it's quite narrow and has a smooth finish. I ended up damaging and scraping the expanded bolt in my attempts to free the Conceal top cap bolt.

- as a few of you described, if I keep unscrewing the Conceal top cap bolt then the expander plug will come apart and fall down into the steerer. It's then quite fiddly to put back together! (On my first expander plug I snapped the little rubber bands which made it even harder to put back together!).

- headset preload on my bike is good and the stem bolts are torqued correctly so nothing should change and the top cap bolt is largely cosmetic for the time being.

- when my bike arrived it had the system top cap on it for some reason. I used an allen (hex) key to undo it and it slightly rounded it out - what are you meant to use with this? If it is a hex key it's either a very soft metal or it's been poorly coated and it's just paint that's coming off.

I might contact Cannondale about this issue and see what they say. To me it seems a poor design thats easy to have issues with.

Update on the issue I had with the expander plug and conceal top cap bolt. I took a look at it the other day again and decided to slightly tighten the expander plug using a 4mm Allen torque wrench. It was just under 4Nm and as I got to 4 (or went slightly beyond) there was a little crack noise, which was the top cap bolt freeing up from the expander plug. I've since put some anti-seize on the threads and lightly tightened (2-3 Nm) the top cap bolt back up so it's working ok now.

I had reached out to Cannondale before this and they were really helpful, replying within a couple of hours. I thought I'd share some of their advice in case it's helpful to others.

They said that this hasn't been brought up as an issue to them before so they didn't think it was widespread. They recommend cutting the steerer flush with the top of the stem for the best fit. 4Nm should be enough to hold the expander plug tightly in place, and the top cap should tighten on smoothly just enough to remove any play in the headset. They recommend adding grease to the expander bolt threads to avoid them becoming stuck (so not Loctite as the manual shows).

They also suggested using some micro spacers (https://shop.fullspeedahead.com/en/prod ... cro-spacer) under the bearing cap to fine tune, which may help with getting the right preload. On this point, my bike came with one of these micro spacers installed under the bearing cap. I had quite a large gap between the bearing cap and the frame which was a little annoying. I told the shop about this when they were doing some work on the bike for me and they removed the micro spacer. Here are the before and afters:


IMG20230925160956.jpg

IMG20231017200543.jpg


IMG20231017200517.jpg
Much better! Only a tiny gap now which isn't visible unless you're at eye level with it and very close. The shop did say to keep an eye on the paint to make sure it isn't being worn away but I think it should be fine.

And still a total pain, removing this stupid sticker! It's stuck pretty good:


IMG20230925160956.jpg

Just a few reference points to help solve your issue or give insight about what may be going on.

[hannawald]

Just a few reference points to help solve your issue or give insight about what may be going on.

Many thanks for some insights that I am not the only one having the issue. Maybe I shouldn´t have checked my bolts. I am just used to doing it on a new bike and usually the bolts settle after one or two rides and I stop checking. But in this case I just needed to retighten the stem bolts to 6Nm again and again so it made me untighten the stem bolts and I found out the top cap is only 1.5Nm and expander bolt the same. I didn´t have headset play (I believe) but my theory is that expander pushing on the steerer with less and less force lead to lower torque on stem bolts.

- my steerer is cut flush with the stem
- I have tried to use antiseize on expander and top cap bolt and I have tried to let it clean, no change. I didn´t use loctite on these bolts.
- I have contacted Cannondale. Their advice was I can try to slightly overtighten the expander bolt, I can try carbon paste on the steerer and of course they recommended authorised dealer.

I use 5mm headset cover + 40mm of spacers so maybe it moves too much. I might try lowering my cockpit by 0.5 - 1cm and cut the steerer a bit.
I don´t want to slightly overtighten anything. I will use grease on top cap threads and a little bit on the bottom part of the head of each bolt.
I am still undecided whether to use grease or loctite on expander bolt (top cap grease, but with expander bolt it might be useful to use loctite).
I will put loctite on stem bolts although I belive it is not the problem here.
I might buy some Carbogrip and spray it on the inside of the steerer (similar to carbon assembly paste but there are no solid particles) - it should not hurt anything.

But as you say it is sensitive like racing car. I have never had these issues. Pretty upset. Maybe I should have bought something slightly heavier but reliable.

[Sup6]

This looks so good!

Spent a little time with tape and metallic silver plasti-dip. Kind of an homage to the SystemSix design.

I’ll take some more pics on the next ride:

[johnpuga1982]

Many thanks for some insights that I am not the only one having the issue. Maybe I shouldn´t have checked my bolts. I am just used to doing it on a new bike and usually the bolts settle after one or two rides and I stop checking. But in this case I just needed to retighten the stem bolts to 6Nm again and again so it made me untighten the stem bolts and I found out the top cap is only 1.5Nm and expander bolt the same. I didn´t have headset play (I believe) but my theory is that expander pushing on the steerer with less and less force lead to lower torque on stem bolts.

- my steerer is cut flush with the stem
- I have tried to use antiseize on expander and top cap bolt and I have tried to let it clean, no change. I didn´t use loctite on these bolts.
- I have contacted Cannondale. Their advice was I can try to slightly overtighten the expander bolt, I can try carbon paste on the steerer and of course they recommended authorised dealer.

I use 5mm headset cover + 40mm of spacers so maybe it moves too much. I might try lowering my cockpit by 0.5 - 1cm and cut the steerer a bit.
I don´t want to slightly overtighten anything. I will use grease on top cap threads and a little bit on the bottom part of the head of each bolt.
I am still undecided whether to use grease or loctite on expander bolt (top cap grease, but with expander bolt it might be useful to use loctite).
I will put loctite on stem bolts although I belive it is not the problem here.
I might buy some Carbogrip and spray it on the inside of the steerer (similar to carbon assembly paste but there are no solid particles) - it should not hurt anything.

But as you say it is sensitive like racing car. I have never had these issues. Pretty upset. Maybe I should have bought something slightly heavier but reliable.

When I cut my steerer tube, I cut it -1mm. I then had trouble getting the momo top cap threads to engage the delta expander plug. That's how I came up with the idea to use the conceal top cap to compress everything first. After everything was compressed, I was able to screw it the momo top cap.

As I worked on my bike later, I wet sanded the bottom of a spacer to get some of that -1mm back. Now I can engage the expander plug with the momo top cap with no problem.

I did try various spacer configurations and found that anything other that flush is too much. If you decide to cut the steer, you could try to wet sand the bottom of spacer to see if that helps preload the system, depending if you cut -1mm.

On another note, I rode my bike for months with the max amount of spacers before cutting the steerer tube. I had no problems with the bolts loosening. So I don't think your "stack" height is the problem.

After re-reading through your post. I think you need a new expander plug. It's a fairly low cost item if you have to buy a new one. It's easy to get and if you still have the problem(s) than you know it's something else. Could be why there's a new one, which I did not know about.

Or, maybe the Momo bar is out of spec?

[johnpuga1982]

I tighten the expander to 4Nm, then top cap to 4Nm, then I release top cap and expander bolt is only 3Nm. Is that normal?

I just took my top cap off and it was about 3Nm, the Handlebar bolts were at 4Nm, and the delta plug was at 2Nm. It's been about two months since I last adjusted my handlebars and about 8 months since I last greased my headset bearings. So it seems I'm having the same results as you. Here are some pictures of what everything looks like after 8 months of riding. For the sake of data, my first ride on this bike was May 9, 2023 and I have 2,124 miles on it.

As noted earlier by someone else, there's some paint scuffing caused by the Conceal Bearing Cap. I went ahead and cleaned/regreased my headset bearings, checked the bottom bracket, and bled my brakes. I'll check the front and rear derailleur torque specs tomorrow.

[Sup6]

Anyone seen a seatpost binder with part number k26083? I can't find any reference to it in my manual or the internet. It's blue instead of grey or pink. Otherwise looks exactly the same. Getting tons of creaking from my seatpost area when tightening. Thinking I need more grease and teflon tape on the back.

Edit: added attachments

[BobbyB]

Anyone seen a seatpost binder with part number k26083? I can't find any reference to it in my manual or the internet. It's blue instead of grey or pink. Otherwise looks exactly the same. Getting tons of creaking from my seatpost area when tightening. Thinking I need more grease and teflon tape on the back.

Edit: added attachments

Can't help you with that specific binder but I have the purple one (v2 I think) and getting some concerning sounding creaks when tightening it up, usually the last Nm (7-8Nm). Can't see any signs of damage to the post or elsewhere, and it doesn't creak while riding not slip at all so I'm not too concerned, but will keep an eye on it given the issues some have highlighted here.

[hannawald]

Anyone seen a seatpost binder with part number k26083? I can't find any reference to it in my manual or the internet. It's blue instead of grey or pink. Otherwise looks exactly the same. Getting tons of creaking from my seatpost area when tightening. Thinking I need more grease and teflon tape on the back.

Edit: added attachments

I believe I have read here that the blue one is the latest version. Mine didn´t creak that much while tightening, I applied grease and carbon paste according to the manual. I remember I tightened to 8Nm, then sit on the saddle and moved heavily front and back. Then I heard a terrible sound:) It probably settled properly, then I tightened again to 8Nm and all good, I didn´t have to retighten again since then.

[Sup6]

I just put it back together and went to town with grease between the wedge and frame (grease side not fiber side). It didn’t make any sounds when tightening for a change. I think the popping sound is the wedge moving slightly when tightening it down.

Anyway, try more grease than you think it needs and see if that helps!


Sent from my iPhone using Tapatalk

[johnpuga1982]

Check out EF Education's bikes for Flanders.

[hannawald]

I tighten the expander to 4Nm, then top cap to 4Nm, then I release top cap and expander bolt is only 3Nm. Is that normal?

I just took my top cap off and it was about 3Nm, the Handlebar bolts were at 4Nm, and the delta plug was at 2Nm. It's been about two months since I last adjusted my handlebars and about 8 months since I last greased my headset bearings. So it seems I'm having the same results as you. Here are some pictures of what everything looks like after 8 months of riding. For the sake of data, my first ride on this bike was May 9, 2023 and I have 2,124 miles on it.

As noted earlier by someone else, there's some paint scuffing caused by the Conceal Bearing Cap. I went ahead and cleaned/regreased my headset bearings, checked the bottom bracket, and bled my brakes. I'll check the front and rear derailleur torque specs tomorrow.

Thanks for your insights it is really helpful. My steerer was cut OK, just at the stem level. So that was not the cause of the problems.I cut 5mm from the steerer height so I now have 40mm incl. headset cover. It was a time demanding project as I didn´t want to cut the cables so I had to cover everything properly not to get any carbon dust inside the steerer or on the floor etc. Then I cleaned the inside of the steerer and the expander with isopropyl alcohol. Then I put a lot of grease on the expander bolt and the top cap bolt. I took carbogrip and sprayed the expander and inside of the delta steerer tube. I put the expander in and tightened to 4Nm. Carbogrip is a liquid which should start to work similarly to carbon paste after 10 minutes. I was super cautious and waited 3 hours, not 10min. After that I used the top cap and torqued to 4Nm. Then I disassambled the top cap and checked the torque on the expander. It held those 4Nm. This is a change from my previous experience.
So I put the top cap back at 4Nm, applied loctite on stem bolts and torqued to 6Nm. Then I went to sleep:) I wanted loctite to have proper time. Today I went for a 70km ride and it seems the stem bolts hold their 6Nm. WHether it is the loctite or the expander holds... I don´t know. I won´t disassamble it obviously as I could brake the fragile equilibrium:) We will see, but I have some hope:)

If I could buy the glued in expander that pros use, I would do it in a heatbeat.

[hannawald]

Check out EF Education's bikes for Flanders.

Not bad but I love the silver pink version (unfortunatelly not available in Europe) or Giro d´Italia version. I might have my bike painted like that some day.

[GrassQ]

In Europe quite many colors in 2024
> 20,
different frames and price points
for example hi - mod framesets 4 colors, hi-mod 2 , 4 colors and hi-mod 1, 2 colors

not so many variables in layouts

https://www.cannondale.com/de-de/bikes/ ... persix-evo

[johnpuga1982]

[sigma]

Check out EF Education's bikes for Flanders.

This was the paint job I mentioned when i asked a few pages back if a new Lab71 colorway was expected. It was lovely in person (for the brief period I saw it at a stop light). Lots of detail in the seat stays and the fork and quite dramatic in the sunlight.