I've got a wobble on

[sirch345]

I agree, definitely worth giving the head bearings a strip down and a visual inspection (the rollers and the outer bearing rings) along with some new grease as already suggested while you're there if there is nothing noticeably worn. Also check that the outer ring for top and bottom bearings are fully home in the headstock bearing housings of the frame.

I find the best way to set the torque for taper roller s/head bearings is, get the front of the bike up off the ground and the bike vertical, tighten the castellated nuts up hand tight, pop the top yoke on, place the steering stem nut on and tighten to specified torque of 103nm. That 103nm for the steering stem nut is important.

The forks then when prompted from the centre position (front wheel pointing straight forward) should turn to the left and to the right in a very slightly controlled fashion. They shouldn't suddenly turn left or right banging up against the steering stops. If they do they need further adjustment by going through the process above again, the same if they're too tight.

Another thing that I keep thinking about is, this is an easy one, visually check the tyres are fitted correctly, check that the tyre bead is even all the way around the wheel rims on both sides of front and rear wheels, also check the tyres are fitted the right way around, they have arrows on them for front and rear fitment. Apologies if someone has already suggested that, it's a bit late now to go reading through all the posts on this,

Chris.

[john306]

Thanks for all the possible causes.
VTR Phoenix mentioned checking wheels/tyres, they were all fine.

I think I'll just bite the bullet and order the steering head bearing kit, While I'm in there I may as well change the lot just to be sure, if nothing else it will eliminate that potential cause, and give me a chance to learn how to do something new, that should prove interesting....

[VTRDark]

Put the new outer shells in the freezer overnight, this help to fit them in place as they will shrink a little. You will need a suitable drift to knock the old ones out. Bottom knock out from the top and top from bottom. You will then a need a suitable sized socket to tap the new ones into place.

[john306]

Thanks carl.
How long would changing over the head bearings take for one of you experienced chaps, and any tips/shortcuts for getting it all stripped down prior to the bearing removal/ replacement as thats been covered so I should be ok there?
Just ordered a kit so it's all good to go one weekend.... hopefully

[sirch345]

Thanks for all the possible causes.
VTR Phoenix mentioned checking wheels/tyres, they were all fine.

Seeing as you've already checked those, you should be able to rule them out now and move on to other possibilities.

I wouldn't worry to much about how long the job will take to fit new bearings. The main thing is to make sure the new outer rings of the taper roller bearings are seated properly, fully home in their housings as I mentioned earlier. I like to use the old outer ring to finally knock home the new ones, but I put a slot in the old ring (with an angle grinder) so it doesn't end up getting stuck in the bearing housing,

Chris.

[tony.mon]

Thanks carl.
How long would changing over the head bearings take for one of you experienced chaps, and any tips/shortcuts for getting it all stripped down prior to the bearing removal/ replacement as thats been covered so I should be ok there?
Just ordered a kit so it's all good to go one weekend.... hopefully

It's a 2-3 hour job.

[bigtwinthing]

use decent grease too.

[VTRDark]

I like to use the old outer ring to finally knock home the new ones

Yep that would do the trick too. Saves killing an old socket. The only thing I find about that is because it's not very deep it's easy to clump your fingers with the hammer holding it in place. I've been there rather than a making a slot I ground a little off the outside circumference so it did not get stuck. Listen out out for the change in tone and you will know when it's fully seated in the frame.

Yeh it's few hours work as you have to jack the front up and remove the front end. Give the inside a good clean out and remove all the old grease and any particles from inside the frame. The worst part is removing the lower race off the stem and getting the new one on. Heat is your friend for removal. Angle grinder or dremmel does the trick but be careful not to cut the stem or lower. Once a bit of heat gets in there it should expand and slide off easily. As for getting the new one on, ideally a bit of plumbers pipe or some other tube the right diameter to fit over the stem is best as then it can be tapped/driven into place squarely on. Yet again a little heat helps here but not too much as it's easy to damage the race and don't set fire to the grease. And don't forget to put the dust seal into place first before the race Actually I would attempt it first without heating up the new lower race. As long as your pipe fits comfortably around the circumference so you can give it nice even gentle clump the new one should slide down OK.

[cheekykev]

I don’t know what facilities you have at your disposal, but I found a good way of getting the bottom race off, the only tools you'll need are a welding plant, a 19mm spanner and a heavy mallet, a hammer will do if you haven't got a mallet.
A bit hard to explain but I’ll try.
I cut a length of steel tube slightly bigger in diameter than the stem/shaft and about an inch longer, welded a cap on one end of the tube, then drilled a clearance hole in the centre of the cap end for a 12mm bolt, and then welded a 12mm nut on top of it.
You can then slip the tube over the stem, tack weld it to the bottom race (preferably with a TIG welder) put a fairly long 12mm bolt through the nut and as you tighten the bolt on to the top of the stem/shaft (kind of using it like a jack) it will pull the bottom race up for you, easy peasy and the heat from the welds just help it along.
Also if cut the old race off the tube, take the bolt out, you can then use the same tube with the mallet to seat the new bottom race down, win win
The good thing about using this method is, it's safe, effortless and less likely cause any damage to the parts

[AMCQ46]

that's just showing off your skills there Kev, us Mortals need to use the angle grinder and a cold chisel.

[john306]

I've got a big hammer and chisel at my disposal, even a blow torch, no welding gear unfortunately.
Bearings should be delivered tomorrow so might get to start it over the weekend, although it's forecast nice weather and would be a shame to have the bike in bits when I could be out and about on it for whatever is remaining of this dry, sunny weekends.
Oh and 2 to 3 hours seems a good time to complete this job, with having to refer to the manual and never done it before I hazard a guess for me of about 3 weeks

[VTRDark]

that's just showing off your skills there Kev, us Mortals need to use the angle grinder and a cold chisel.

Definitely showing off Bloody clever though.

The thing with the angle grinder over a blow torch is the combination of heat and cutting.

[firestorm_al]

This may seem a bit random but it might be worth checking the condition your front sprocket. Even some slight wear on the sprocket can "grab" the chain which can be transmited through the bike in all manner of strange ways.

Al.

[john306]

Update.....

I replaced the steering head bearings yesterday, it took a good portion of the day but that was constantly referring to the manual and double checking everything ans not rushing.

Took the bike out for a ride this morning and the wobble has gone, it's like riding a different (better) bike.
I've got more confidence through bends and everything feels nice and tight again as the general looseness has gone.

Thanks for all the help, I just need to tweak the suspension setting to suit now

[Kev L]

Good news fella, well done