Front wheel judder under braking

ascurrell

Hi Guys, got a little problem with the front wheel braking.

Just got the bike out and have changed the wheelset from Fulcrum 5.5's to near new Forza [4za] Cirrus. Iv'e noticed under braking the front wheel judders. I've adjusted the blocks as they were slightly out of line from previous wheelset.
The calipers are 4za's, [look nice but not the best I think]. The wheel runs smooth with no deviations. I don't remember it happening with the Fulcrums.

Any help o suggestions would really be appreciated, Thanks, Scurry

GavH

Juddering could be a wheel that's out of true or possibly your headset has worked a bit loose?

Matthewfalle

Headset, stem, bars, calliper, skewer - need to check all tight.

Anyone else?

kajjal

Have you cleaned the rims and brake blocks ?
Is it at any speed or just when you pull the brakes on hard from speed ?
Is it smooth all the time unless you are braking ?
Are you a heavier rider on light weight wheels ?

Matthewfalle

Old pads on new rims? - Old pads have worn to old rims and now new profile of new rims and Old pads means that the Old pads on the new rims aren't profiled liked the Old pads were on the Old rims not the Old pads on the new rims and now the new rims aren't profiled with the old pads and the juddering is caused by the Old pads/new rim combo?

ascurrell

Thanks for input and suggestions,
I had just cleaned the rims before post but won't get to test until tomorrow.

It's only really noticeable going downhill, it seems smooth the rest of the time

Um, yes I am a fat git, approx 96kg. The wheelset weighed 1666 grams with skewers [not originals]
Front weighed 710 grams That is an interesting point.

"Headset, stem, bars, calliper, skewer - need to check all tight." ---- I did check all of these before last ride, adjusted headset slightly [no change] all of the set up was the same as when I last used the bike on the other wheels.

"Juddering could be a wheel that's out of true or possibly your headset has worked a bit loose?" Wheel is true, headset seems ok

Can tyres have an effect, I've noticed a couple of slits.

ascurrell

Matthewfalle wrote:

Old pads on new rims? - Old pads have worn to old rims and now new profile of new rims and Old pads means that the Old pads on the new rims aren't profiled liked the Old pads were on the Old rims not the Old pads on the new rims and now the new rims aren't profiled with the old pads and the juddering is caused by the Old pads/new rim combo?

The old pads aren't that old but what you are saying makes a lot of sense, later I will remove the old pads and have a look.
To be honest I am hoping it is that as it's easily remedied,

Thanks to everyone for the help, much appreciated.

Matthewfalle

On a separate matter, how bad are the slits? Not bad enough to give you dead disease I hope.

ascurrell

Just an update, I changed the pads for some Clarks CNC-500C and there was a big improvement. Need to bed in a bit better but instant difference.
I think the suggestion of the old pads wearing to the previous wheel etc was the right call.
Many thanks again, Scurry