upgrade steering head bearings... i'm stuck

i searched on the forums but came up next to empty. i bought the tapered steering head bearings from chacal and i'm a little stuck in putting them in. there are two different sizes, i'm guessing (and hoping) the thicker one goes on the bottom. Is this true?

Also, what components do these upgraded bearings replace? i've used a puller to remove the races that were pressed into the neck of the frame and pressed the new ones in. the thinner one on top, the thicker one on bottom. The top one has a small lip exposed and it it in all the way, is this normal?




I'll add links to some pics i took of where i'm at now. Also, i'll add a link to a parts diagram from yamaha... can anyone let me know which pieces from the diagram are eliminated in the upgrade and where my new parts (bearings and seals) go? Thanks a ton!!!

 

call the local dealer, give them the part number and ask them which location they go in, they should help.

 

Actually, chacal PM'd me with the info I needed for this one...

"Okay, the only parts you'll re-use from your original system is the ring nuts (used to pre-load the bearings) and the top bearing cover.

Everything else (ball bearings, their upper and lower races, and
seals) goes into the just-a-memory-now pile.

The UPPER bearing/race is the one with a smaller ID, and may be marked on the bearing or the wrapper that they come in as such:
99-3505 brg. 25Y-Q8Y5

The LOWER bearing/race is the one with a larger ID, and may be marked on the bearing or the wrapper that they come in as such:
99-3506 brg. 30Y-Q8K5


The key point to remember is that the races are matched to the bearings, and that the bearing with the smaller ID is the upper bearing, and thus its matching race is the upper race.

The upper and lower dust/grease SEALS are the same top and bottom, and of course they are the first and the last items that go onto the steering stem itself.


Here's some good info from another forum on what is involved in the tapered steering bearing installation procedure:

Put frame races in freezer. Grease lower bearing with bearing packer and place in rod oven or other source of low temp heat. Yank the front wheel and fender. Drop the forks. Remove the headlight and gas tank. Unbolt the dash, etc. Remove handlebars. Most of that stuff can hang by the wires, but you might have to unplug the odd connector. Remove the centre nut, lock nut from the upper triple tree.

Remove upper TT and drop steering stem/ lower TT from frame. Extract races from frame with drift or puller. Remove race from lower TT -- this is the tricky one. I usually wind up deeply scoring it on two sides with a dremel tool and then inserting a cold chisel into the score. A whack with a hammer splits the rest without cutting into the stem. I've also had success with a pickle fork and acetylene torch. Put the lower TT into the freezer -- maybe on a bag of ice cubes to cool it faster.

Chilled races drop nicely into the frame on assembly. Just make sure you
know which is which -- they are different. 48YS is upper, 48KS is lower. And make sure they face out! The wide end of upper is up, wide end of lower is down. The warm bearing will slide nicely over the chilled steering stem.

Grease upper bearing and commence assembly. Don't get carried away
tightening that centre nut. It needs to be adjusted to give very slight drag
and no play. Work it back and forth a bit to distribute the grease and check
again. Retorque will still probably be required after a few hundred kms.
Assemble everything else.


Hope all this helps!"

 

I then sent him this...

"That does clear things up A LOT. I just wish i had asked before i pressed the wrong races in. So just to be clear, I'm NOT using the steering seal (part #2 in the diagram)? I should have dust/grease seal, lower bearing, lower bearing race, neck, upper bearing race, upper bearing, dust/grease seal, top bearing cover, ring nuts... in that order?"

He replied and told me that I was correct.

 

Thanks for the update. I was actually thinking about doing this and it helped clear up a few issues I was having. Maybe I'll give 'er a go now. One last thing if ya don't mind, about how much were the bearings and everything else needed to get this job done?

 

Chacal has everything you need. Send him a PM and he'll let you know his prices on everything you need.

 

My local Yamaha dealer charges $30 for the "allballs' Bearing set. Be aware that the ese Tapereds don't fit very well Always protruding at least 2mm out the top. Thi also make installing the thing that pis passed off as a Seal (in the Allballs Bearing/kit package as a poor joke as it Cannot seal like the removed one did.
We all have fallen for the Tapereds are "better' than the venerable Yama Ball bearing races..Brochure Babble
Well, Bollox to that... simply ain't true in the cold light of day.
The oem bearings work 'just fine' and surprise! have lived at least 20 years so far. Cheap to replace too and the oem seal actually even keeps a 'bit' of the water out . Oftem upgrades are not an improvement just 'different' than what was there before.

 

I just finished my bearing replacement and it all fit very well, seals just fine, and I didn't have to worry about little steel balls rolling away on me. Weather or not it is truely an "upgrade", it was still worth it to me to get them just for the ease of installation alone.

 

OK - so I'm not the only one struggling with tapered steering head bearings - I do have slightly different problem however, I just bought an "82 XJ750J Maxim and the lower triple clamp plate sits approx. 1/4 to low - so low in fact that steering stop misses the boss and the clamps contact the tank at full lock! The tension on the bearings is set correctly but the center shaft thru the head sits so low that it only has one nut on it - (no threads exposed for the lock nut) I suspect that the previous owner installed the tapered bearings without replacing the lower dust seal as the lower bearing sitts atop the the shoulder of the seal instead of fitting flush - anyone know if my guess is correct???? Tnx, j

 

I'm not sure i'll be able to come up with an answer for you or not but i'd imagine we'd have better luck with a diagnosis if we had a pic to look at.

Just a thought, but the original lower bearing race is about 1/4" and was a PITA to remove. perhaps the PO left it there? that could account for the extra 1/4".

 

Looking at the pix with the original post - I'm thinking that is exactly what happened - after cleaning things up and tearing down a little farther - it looks to me like what I thought was part of the bottom seal is actually the old lower race!! Gonna pop that sucker off and see if everthing lines up.

ajeepsterman - '82 XJ750J Maxim - project - going backwards right now!

 

My tapered kit didn't come with any type of seals, and when I installed the top-bearing race (the 48YS racer as stated in the thread) it protrudes above the actual neck opening.

Is it supposed to be like that, and were there supposed to be some type of seales included?

 

Some of the tapered bearing kits do NOT come with the upper or lower seals.........and use a cheaper grade bearing, to tell the truth.......the one that I offer (like bluepotpie received) do come with the seals.

I have not had any reports of the races being the wrong size (i.e. too tall) and have installed them on three of my own bikes and they alsways fit like a champ!

 

The kit I have has the exact bearing and race numbers that he mentioned in his post. My top bearing race protrudes exactly like is shown in the first pic in this thread.

Any idea what I'm supposed to use for seals?

 

Short-circuitz.....by chance did you reverse the upper and lower races (they are different in height)....the pictures in this thread show the INCORRECT races installed (upper and lower races reversed). If so, you have to swap them around..........

 

Nope, as he stated in his response where he posted the correct race numbers for upper and lower, the 48YS race is installed in the upper, and the 48KS is still sitting in the freezer til after supper when I was going to go out and install it. I just finished installing the lower bearing (30Y-Q8K5) on the stem and ready to go.

 

my upper race did extend a few mm out the top of the neck (with the correct one installed) but it didn't affect the operation at all.

 

Thanks...got it back together today (since I finally had some time to myself).

Now to source up a new throttle sleeve, because the plastic on mine brokoe when I was trying to install my new bar end mirrors.