Pinarello FP2 - Fork Movement Problem - Help very much appre

rjsdavis

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Hello to all

I've recently acquired an FP2 for my eldest, after his original Pinarello shattered underneath his backside whilst riding. We spent a nice bit of time building it up, and all seemed to go well following the build finish (apart from discovering that the rear brake bridge is so damn thick that normal Chorus rear brakes don't fit, as the bolt/nut combo isn't nearly long enough!). A brand new Pinarello carbon fork steerer expander top cap was fitted and adjusted until "headset rock" was removed. It all seemed fine.

It's been ridden twice, and I was checking it last night to see that all was still well when I noticed some very slight movement in the headset / fork area.

The problem is definitely with the forks, everso slightly rocking backwards and forwards within the headtube. If I've grabbed a handful of front brake and gently rocked the bike backwards and forwards, you can't feel it. However, if I lean right down and rest my chest on the handlebars whilst rocking the bike backwards and forwards, I can feel some slight "knocking". After a few minutes of ensuring that the front brake wasn't loose in the fork, I could feel ever so slight movement where the head of the fork is actually "moving" within the headtube. With my fingers covering the gap between the top of the fork and bottom of the heatube (it's an integrated headset, so really no gap at all), I can feel the knock / movement of the fork crown. I'm confused.

I've obviously tightened the top cap, but this is now at a stage where it's really pretty tight to do up even further. I'm a retro guy, and don't really like aheadset's anyway, but I certainly don't feel like I want to tighten the expander plug any further as I don't want to damage the carbon steerer! There is no restriction in lateral movement as you turn the bars, which turn freely and easily.

Therefore, I'm not sure what to do next? I'm reluctant to really chance overtightening the expander plug in the steerer. Is the most likely explanation that the bearings are just shagged and require replacement (most likely the bottom one which obviously suffers most of the usage stress) and this is bearing wear I'm feeling? Or could there be another explanation?

The only slight issue in my mind is that this was a used frame, and I'd hate to think that I've ended up with something damaged, but wanted to try and get to the bottom of this asap in case it is.

Any guidance/suggestions would be very much appreciated. Cheers guys...
 
Re:

Sounds like it just needs tightening a little more. Sometimes things will settle in and need tightening after a couple of rides.

But - did the bearings sit correctly in their seats? Did all the parts go together as they should? It's unlikely to be the bearings themselves, as they usually go notchy and rough, without actually allowing movement as you described. And if you used the correct expander wedge/plug, then further tightening will not clamp it more into the steerer, but will pull the stem down and tighten the bearings.
 
Has the top cap bottomed out on the top of the steerer?
(And you are undoing the stem bolts when you adjust the top cap?)
 
Thanks for these two replies - I now feel like a proper tool.

It would appear that the cause was that I hadn't undone the fecking stem :facepalm: , before tightening the top cap/expander plub. I've now done this, and the rocking has gone. I suspect that the headset bearings (that came with the frame and were used) are virtually at the end of their useful lives, as I can feel that now that the top cap has been properly tightened down, a light notchiness (just like where you get a bearing pit in an old school bearing race from when the headset has been run loose) is apparent, so that when the bars are level and pointing dead ahead, the steering needs to be nudged out of the notch and is then smooth, and it likes to self-centre itself back into the notch. It's not bad enough to warrant the change of bearings just yet, but it will be at the end of the Summer season.

Anyone know how easy it is to change out the pressed in bearings from the head-tube? I've got a VAR headset press for old school cups, so would figure pressing the new ones in will be easier the removing the old ones.... Also, sourcing the actual bearings themselves?

Thanks for the help so far - it got me right back on track.
 
Depending on exactly which model of headset it is it may be that the pressed in parts remain in place and you simply pop the bearings out. A light (and accurate) tap with a screwdriver in the right place usually sees them out.

rjsdavis":2rsjfgis said:
now that the top cap has been properly tightened down

And when you say properly tightened, you do realise that the top cap should only just be finger tight. 1 or 2 Nm. Thats why the very earliest ones were plastic, so if you overtightened, the cap split before you did any damage!
 
Ah, just checked. Looks like it'll be a bike shop job. Interference fits on top (definitely) and bottom (as far as i can tell). May be a bugger to get them out


Fairly standard bearings by the looks of it. You'll need a bit of googling to make sure on the model year and bearing sizes.
 
mattr":1bgclugf said:
And when you say properly tightened, you do realise that the top cap should only just be finger tight. 1 or 2 Nm. Thats why the very earliest ones were plastic, so if you overtightened, the cap split before you did any damage!

Yep - it was just to highlight the difference between what it is now, and what it was....
 
The bearings can probably be tapped out quite easily, but getting the new ones in straight might be harder, depending on the model of headset and bearing. Most bearings are a standard size (the ones on my pinarello are, anyway), so easy and fairly cheap to source.
 
Interference fit = bloody tight press fit.

All of mine are either drop in or press fit (I.e. you can do it with your fingers or a light tap with something)

Except the Chris King.
 
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