Taper Steering Bearings - part numbers and setting

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AMCQ46
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Taper Steering Bearings - part numbers and setting

Post by AMCQ46 » Mon Feb 08, 2010 9:31 pm

OK , numbers as follows

the kit is HCH-903R [COL001]

the bearings should be
Bottom:- 30 inner Diam by 55 outer diam by 17deep [should be marked 32006]

Top;- 26 ID by 47 OD by 15 which is a special, and not in my normal bearing supplier hand book and I cant remember the number on the part.



The taper bearings have a different numbering system to the cup & cone so I think that is what is causing the confusion, hope that helps and you get them fitted OK.

Also note the setting process [torque preload] for tapers is not the same as for the std balls. The standard part requires a good preload torque [it is in the haynes manual, but I dont remember], but if you do that to tapers you will get a very strange low speed steering wobble, as they will have much too much force locked in. You should set tapers just above hand tight where there is no slack and a slight increase in the torque to turn the steering head.

I do this with the wheel off the ground, and look at how easy the steering is to knock off center, and if the bars will fall to full lock under their own un ballanced forces. if you move the steering off center and it wont fall to full lock [and it did before you thightened it] then you are too tight.

Also you will find when you tighten the steering stem nut, that will further preload the bearings, so you may have to slacken them off to compensate for this final assembled condition. Always do the final test with the top yoke fitted and the top nut torqued down, then you will have it correctly set.

Hope it makes sense
Last edited by AMCQ46 on Wed Aug 23, 2017 12:22 pm, edited 1 time in total.
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sirch345
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Re: Taper Steering Bearings - part numbers and setting

Post by sirch345 » Tue Feb 09, 2010 11:35 am

Good write-up AMcQ :thumbup:

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Miztaziggy
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Re: Taper Steering Bearings - part numbers and setting

Post by Miztaziggy » Sat Sep 03, 2011 5:50 pm

AMCQ - what does the low speed steering wobble feel like?

I fitted these during the week, and tested today at what I thought was correct tightness, but the bike feels odd. I cant tell if it is the head bearing or the new tyres though as I just replaced a set of very flat tyres that came on the wheels I bought, with a set of very rounded racetecs.

It feels very quick and easy to turn, going round bends quickly didnt feel as 'sure' as they did before and the slightest movement of the bars moves the bike a lot. Almost like the steering is too loose and easy to turn?

At slow speed though, it will pull to one side slightly, and when corrected, will start to go the other way. I cant tell if it was the wind blowing me about or it was the 'wobble' or 'weave' you mention??
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AMCQ46
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Re: Taper Steering Bearings - part numbers and setting

Post by AMCQ46 » Sat Sep 03, 2011 6:05 pm

The weave is below 30mph and will effect you in a straight line, so that doesnt sound like what you describe .

Change of tyres can make a big difference, and it almost sounds like you have too much steering head angle, and is turning in too fast, so with these tyres you need a bit less spacer under the shock, or lift the yokes back up the forks by 3mm.

if you followed the instructions on setting taper rollers that I posted at the start of this thread, then you will be fine, if in doubt set them slightly looser than you think (when you tighten the top yoke down it takes out a lot of slack), and as long as you don't feel a clunk under braking you are good.

Hope that helps
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Re: Taper Steering Bearings - part numbers and setting

Post by Miztaziggy » Sat Sep 03, 2011 6:29 pm

Thanks, that does clear up the too tight question then. I tried to tighten till they fell under their own weight with the front in the air, but even with the head very very loose, they wouldnt really fall to full lock, so I hand tightened then went back a half turn. Tested and it was clunking like my old bearing when I applied brakes. Tightened another turn and tested, still slight clunk, so tightened another half turn and clunk gone. I left it at that and lifted forks back up.

As for adjusting the steering head angle, the forks are already right at the top on the clips, and there is no spacer on the rear shock, so not sure what I can do there?
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darrenmartin
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Re: Taper Steering Bearings - part numbers and setting

Post by darrenmartin » Wed Nov 07, 2012 8:19 pm

I was pointed in the direction of All Balls Racing products :roll: i hope these are gunna be ok :confused does any one know the parts numbers for these.....the only code no's i can se are 22-1020 on the box and on the smaller bearing 32005x/26 and the larger bearing has 99-3519 any pointers would be gr8 :thumbup:
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AMCQ46
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Re: Taper Steering Bearings - part numbers and setting

Post by AMCQ46 » Wed Nov 07, 2012 9:14 pm

Darren,
The all balls set will be fine as long as it was a kit for the VTR1000. The part numbers above are my if you want to try any by the bearings individually
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Re: Taper Steering Bearings - part numbers and setting

Post by darrenmartin » Wed Nov 07, 2012 9:33 pm

:thumbup: cheers m8 :wave:
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Re: Taper Steering Bearings - part numbers and setting

Post by darrenmartin » Sat Nov 10, 2012 5:20 pm

Has any 1 took any pic of the change over :think:
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Re: Taper Steering Bearings - part numbers and setting

Post by tony.mon » Sat Nov 10, 2012 5:31 pm

You don't need pix, the seat (where the outer races are seated to) have little half-round cutouts where you can get adrift or a long screwdriver to to knock them out, and the new ones go in so they fit like the old ones.

Just don't torque up tapers lie you have to do with ball types.
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Re: Taper Steering Bearings - part numbers and setting

Post by rollingthunderx2 » Wed Nov 14, 2012 2:36 pm

I'm pretty sure if you fit tapered bearings the top dust seal wont fit, you need to get a bearing kit with a new set of seals.?
The bottom one will probably get trashed taking the bottom bearing off anyway.So make sure you have all the parts you will need before you start.
An easy way to get a bottom inner off the stem is weld a couple of lines of weld around the bearing surface and when it cools it loosens the bearing, a knock on a piece of wood will release the bearing.
Cover the stem to stop weld splatter sticking to it.

When you put the bars back on make sure the cables aren't tangled.
And use waterproof/lithium grease.

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