Gap on Headset bearing cover

[andsaw]

Just put new top bearing on my headset and the bearing cover (conical bit) that has a dust seal on the bottom, is not touching the frame like it was before, the gap between the cover and frame is a tad over 1mm, i know the previous bearing had a bigger outside angle face than the new bearing making the newer bearing sit higher up on on the frame face thus getting that gap.
The only difference between new and old is the tightening of the preload, the new one has a more pronounced its tight feel and you know when its adjusted enough, and the old had a more not so sure how tight you should go feel, is the new one ok and not to worry about it or should there be no gap and need say a 1mm shim, its on a cannondale supersix evo 105.

 

[the_mikey]

Seems a bit strange to me, it really does need closer inspection. Is the new top bearing identical in appearance?

 

[lpretro1]

You should be fitting a bearing with the same angles as the old one. You should not have a gap where the bearing cover fits

 

[the_mikey]

You should be fitting a bearing with the same angles as the old one. You should not have a gap where the bearing cover fits

+1

 

[Citius]

+2

 

[andsaw]

Been doing some comparisons, and the bearings are exactly the same as each other except the old ones outside angle has an ever so slightly bigger face, and did some in frame comparisons and was hardly noticeable except it was sitting about half a mill higher, for which i could account for having the smaller angle face on the new one,when i retried fitting the new bearing it did sit better and there was an ever so slight gap between the seal and frame at the back and nothing at the front.

 

[accountantpete]

The outer edge is angled - so if you have the correct angled bearing (45x45) then either the depth of the bearing is thicker than the old one or the OD (outside Diameter) is greater.

The size of the face of the angle will have no effect.

 

[andsaw]

Done some photys, blue one is the new and orange old, the edge to edge one is old left and new right, and the side on frame is fiirst attempt at fitting ending no 78 and second attempt is no 83, measured the o/s angle and both exactly 45, http://s1177.photobucket.com/user/andsaw/library/Headset bearing

 

[accountantpete]

What they appear to have done is change the size of the bearings - the blue seal is a bit wider than the orange - and this has pushed out the bit where the angle starts on the inner so that the bearing rides slightly higher.

It should be perfectly sound - but to check it is getting enough contact put some marker on the ledge in the headtube and drop the bearing in and then pull it out and see.

Have you changed the bottom bearing?

 

[lpretro1]

New bearing is deeper - so it will sit higher - only needs to be a mill out to be wrong