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Discussion Starter · #1 ·
OK,
I adjusted the steering head bearings this past weekend because not only was it time but I've got the dreaded deceleration death shake. I want to share what I learned and how to do it for the guys that haven't tackled this project yet. First you will need a few specialty tools, a 27mm socket (deep is preferred) a head bearing spanner wrench, (you'll notice I chopped mine down as short as I could make it) and someway of lifting the front end off the ground.

Step 1- you have to remove the handle bars to loosen the 27mm nut, loosen the 2 pinch bolts on either side of the triple clamp, and take out the 2 bolts underneath the triple clamp that hold the turn signals on. Re-install the handle bars to wiggle off the triple clamp. Remove the locking collar and take off the locking nut, now you can adjust the head bearing nut to 13 lbs per the manual. (this must be done with the front end off the ground otherwise you will not be able to get the triple clamp back on, I know cause I had to do it twice :frown2:) Now, after adjusting the nut to 14 lbs and putting it all back together and taking it for a test drive I found that it was no better than when I started. I spoke to a service tech at my local dealership and he was kind enough to tell me not to be afraid to over tighten the head nut, which I did, just until I met resistance in torquing it, probably about 16-17 lbs. I put it all back together, took it for a ride and the thing rides like its on a rail!!:grin2:. the bad news is I still have the deceleration head shake. I'm now thinking it is an imbalance in the front forks because it only happens when I load the front end on a deceleration and let go of the bars. (I know, don't let go of the bars! right :surprise:)

I'm open to any and all suggestions from you guys in the know. And, if this helps someone else great, glad I could do it.
 

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I'm wondering if torqueing the Crown nut down to say 25ft lbs. I know like on all my YZ Dirt Bikes 250 and 450F, you torque the Crown Nut down to 27ft lbs initially, then back it off one turn and retorque it down to 5ft lbs but I retorque mine down to 10lbs cause it helps with the loose ness in the bars and gives it that stabilizer bar feel.
Now.....on Street Bikes I'm not sure but would think it would work the same way.

I too have noticed what you experienced just in my few rides I have rode mine. When you let off the throttle and o e hand is on the bars,you get that slop of back and forth motion in the bars.

I believe 25lbs torque on the Crown Nut would be good.
 

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Discussion Starter · #3 ·
Cap't,
The book calls out an initial torque of 38 ft lbs, then a final torque of 13 ft lbs once you have set the bearings and grease. My experience and the dealer that I frequent is that 13 ft lbs is not enough, hence taking it to about 17 ft lbs.
I am working with the dealership now trying to get them to do a warranty look see on the front suspension to see if there is anything there.
I'm also anxious to burn up these tires and put on some nice street tires to see if that helps.
 

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Head Wobbler

I am following this thread with interest because at just over 4,000 miles I have now become a member of the Head Wobblers. It didn't do it back when I had half as many miles on it.
 

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Having grown up riding older Triumphs, I know ALL to well the tell tale signs of steering head bearing wear and/or out of spec torque on the nut. Even if you don't experience the head shake or wobble, it can feel like the front tire pressure is low.
Approaching the 4,000 mile mark, I too am experiencing the loose nut (that's what she said). 😉I am choosing to live with it for now and try to get through the riding season.
 

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Knock on wood, but my SCR is still rolling steady and true...although it's still under 3000 miles.

I installed the All Balls tapered steering head bearings on my '74 Z1 this summer, not a difficult job but I hear it's more of a challenge on the SCR?
 

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The method I've used in the past is yes, tighten down to 30 or 40 ft lbs. Then back off and re-tighten. When the bike is on a lift and the forks are centered, a gentle push to one side should result in the forks slowly rotating until they hit the stop. If you push them and they flop side to side, the nut is too loose. If you push them and they don't rotate, or stick in place, or otherwise don't smoothly rotate to the stop on their own, the nut is too tight. Back it off, and then re-tighten.

Charles.
 

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Also note that after torquing down move the forks back and forth several times. It will loosen up. Tighten again and repeat until it stops loosening. Now everything is seated and you can back off and set the proper tension.

Charles.
 
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