steering head bearings

[Locomotive]

I finally had time to do a few things to my bike and one of them was to tighten up the head bearings. Now the wobble is gone but the bike seems to wander a bit on the road. Im thinking that i tightened the nut a little too mutch. What is the best way to know just how tight the steering bearings have to be ? I had my bike on the centerstand when i adjusted mine but i gave the nut a little extra snugness and that might be where the problem lies. Any ideas ?

[Freebird]

The "wandering" is certainly a sign that you have them too tight. It's hard to describe exactly how to tighten them properly. I just put it on a centerstand or bike stand and gently swing the front end so that it bounces off the left or right stops. It should rebound and then gently come to a stop without swaying back and forth.

[Marcarl]

You're at the perfect point. Just back them off a little, just enough to say that they moved,,,, so little in fact that sometimes just riding a careful 10 miles will solve it,,,, maybe a 1\32 of an inch and it should be perfect.

[bobcat]

I've always adjusted the steering head with the bike off the center stand...I tap the spanner nut just enough to get the looseness out..As freebird said its tough to describe how tight to go, Its more of a feel thing so I'll say tighten it until its barely snug..You'll get a better feel for it with the bike off the center stand..

[Venturous Randy]

The number one problem on these old bikes is not that the bearings are tight enough, but clean enough. I have redone the bearings on several 1st gens and the first thing to do is clean the bearings real good, feel for any imprints on the bearings and then repack and reassemble. Every one I have taken apart had dried grease that made the head sticky. After getting everything clean and regreased, I have found that what worked best for me was to put the bike on the centerstand and put a small jack under the front of the engine and raise it until the rear wheel touches the ground. This will allow the front end assembly to be easily moved from side to side. It will also allow you to feel for anything rubbing anywhere like brake hoses, wiring harnesses, etc.

The steering should normally want to fall to one side or the other. In tightening the bearings, I over tighten them until I feel a little restriction and them back them up a little.

Now, if you did not clean and regrease your bearings to start with, you will not get what the bike is capable of for correct tracking.

RandyA

[CrazyHorse]

I finally had time to do a few things to my bike and one of them was to tighten up the head bearings. Now the wobble is gone but the bike seems to wander a bit on the road. Im thinking that i tightened the nut a little too mutch. What is the best way to know just how tight the steering bearings have to be ? I had my bike on the centerstand when i adjusted mine but i gave the nut a little extra snugness and that might be where the problem lies. Any ideas ?

 

Wandering = Too Tight

[Geobob]

I suspect this is all in the manual but I am a bit lost about what is holding things in place. The two lock type ring nuts under the top triple tree seems to be the adjustment while the nut on top of the triple clamp holds the adjustment in place. There are two ring nuts with a lock ring between them. I would assume the bottom one is what you would adjust to the proper torque and then the lock washer and top ring tightened down to hold the lower. Then the lock wash tabs keep the two in place. I guess the top nut on the upper triple clamp would also keep the whole thing in place but I wonder if it also does not put additional pressure on the bearings.

 

I guess I need to read through the manual to see what Yamaha thought about the process. It does sound like a good idea to clean and grease just to check it out for where. It was replaced but it was many years ago.

[cowpuc]

I have used a small weight scale to do the final set on my bikes for many years - scales the shooters use to measure hammer or trigger pull (have used em for double duty thru the years,, I'm a cheap bugger = multiple use of specialty tools = another flaw in my character:duck:) but the method has served me well. What have done on both my MX/Harescrambling race bikes, street bikes and even quads/three wheelers is as long as I know I have good bearings in the steer head and its lubed properly I will run the bottom spanner nut down and torque it to 5 ft pds, move the forks from lock to lock several times to displaced any grease from between the bearings/races, retorque to 6. Then put the spacer (some are rubber, some are steel) over the bottom spanner and spin on the upper. I like to hand tighten the upper as tight as I can get it and then finish it off with a nudge with a spanner so the spanner notches between top and bottom align. Reset the upper, toss on the stem nut.

Center the bars so the front wheel is point straight ahead (dont have to be perfect). Take a tie wrap and zip it loosely on the end of each bar. Hook my trigger scale to the tie wrap and at a perpendicular angle to the grip lightly pull and watch for movement in the grip. I like to see movement at about 12 ozs of pull in both directions off each grip.. If its lacking I take the upper back off and tighten the upper spanner nut by one notch to realign again (hold the bottum nut with a spanner to nudge against),, if its tight I back off one notch = then check it again.

I know,, all sounds really old schoolish but the above has done ok by me...

 

Cheap Chinese Scale that would do the job? Something like this:

https://www.ebay.com/itm/50KG-5G-Hanging-Scale-Digital-Backlight-Fish-Luggage-Pocket-Weight-KG-LB-OZ-SA/283010907453?epid=2169391938&hash=item41e4c3bd3d:g:G6IAAOSwd0BVwtEo

[Geobob]

Thanks for the advice.

So the upper ring nut is used to find tune the torque on the lower nut.

 

I got mine apart last night and the bearings and races looked good and well greased. It also felt snug before taking it apart. I am left with assuming my wobble was the result of the fork oil levels not being correct. I should have measured what came out but I did not so we will just have to hope it was.

[Freebird]

If you are absolutely convinced that everything is correct with the front, then the problem could be in the swingarm. A lot of people just assume that a wobble is caused by the front forks, head bearing, etc. but don't consider the rear of the bike. If there is play in the swingarm due to loose or bad bearings, that can cause a wobble.

[Geobob]

If you are absolutely convinced that everything is correct with the front, then the problem could be in the swingarm. A lot of people just assume that a wobble is caused by the front forks, head bearing, etc. but don't consider the rear of the bike. If there is play in the swingarm due to loose or bad bearings, that can cause a wobble.

 

When I get done with the front end I am moving to the rear. I have newer rear rotor to put on and I plan on pulling the drive shaft to grease the splines. I have grease fittings in the swing arm and believe it is still good. I had it apart last year and I thought it looked good but I take a closer look this time. I know I have one slightly corroded sleeve/bushing that I should look at replacing but its been that way since I put the grease fittings in 10 -15 years ago.